Several confessions are necessary at the start. Foremost of them is that I am not a gardener and have grown none of the species mentioned below save for a few as part of greenhouse studies. Next in importance is that I am a taxonomist, and worse yet, an academic one, so that what is below is more voluminous and erudite than most may wish to have placed before them. I will leave it to you to decide what you might wish to review and to ignore. Further along is the realization that time prohibits my fulfilling my own desire to fully illustrate this presentation. That will have to await as my time at the moment is largely occupied with preparing treatments of Eriogonum and its relatives for Flora of North America and the last volume of the Intermountain Flora. Finally, this is a document that with your help and contributions might be worthy of retaining on the web for future reference. We shall see.

     My association with the wild buckwheats began during the summer between by sophomore and junior year at Utah State University (1961) when I worked for the Bureau of Land Management in northwestern Utah doing range surveys. I had taken a course in plant taxonomy from Arthur Holmgren, and found collecting to be a worthy exercise (something I had done routinely since a junior in high school), and so I made numerous collections over the summer. What I did not expect was that I would find new kinds of wild buckwheat.

     Art suggested I send duplicates of my specimens to George Goodman at the University of Oklahoma and to John Thomas Howell at the California Academy of Sciences. Both wrote back saying they did not know what it was, and Tom Howell suggested this would be a good genus for a young person to study. To further his suggestion, he sent me a copy of Ms. Susan Stokes's revision of Eriogonum published in 1936. Now worn and battered, that copy remains a prized possession.

     It was Art Holmgren who suggested I follow up on what Tom Howell had suggested. I asked him how, and basically he said go through everything in the herbarium and learn what the species were. Furthermore, I should compile all the information I could on the genus ─ all names and publications included ─ and come see him when that was done. Four months later I showed up in the Intermountain Herbarium with several notebooks of copied pages and asked what I should do next.

     The answer was to start monographing the genus; I have been trying to do that for over forty years.

     The genus has been a wonder avenue to botanical explorations and discoveries. Even today new kinds of wild buckwheats are still being found in portions of the western United States and northern Mexico. It is fun to travel the West and see plants I have named, and it is particularly exciting even still to find something new for the first time.

     What is presented below is a rather technical discussion of Eriogonum. There is a focus on those kinds that would be suitable for the rock garden, not just those from the alpine regions. You will find initially a discussion of the genus and where it fits in the plant kingdom, and especially as it relates to other genera in the knotweed family, Polygonaceae. The bulk of this presentation is devoted to species I feel are worth of consideration in the garden. These suggestions are based solely on my view of what might be appropriate in cultivation. Not everyone will concur and that is fine. I trust I have not missed some that you might feel are worthy; if so, I will attempt to include them.

     The genus Eriogonum, or wild buckwheats, is one of the largest genera of plants found in North American north of Mexico, being exceeded in numbers only by Carex, Astragalus and Penstemon. The some 253 species of Eriogonum in this area occur from the off-shore islands of California to the coastal plains of South Carolina, Georgia and Florida, and from the Eagle, Alaska and Yukon area in the north to the Mexico line from the Gulf of Mexico to the Pacific Ocean. Elsewhere, the genus is confined to Mexico, being found to the trans-volcanic ranges of central Mexico and just north of La Paz in Baja California.

     Eriogonum is one of some 21 genera belonging to the subfamily Eriogonoideae of the knotweed plant family Polygonaceae. The subfamily is restricted mainly to the arid regions in temperate portions of the New World. In South America, members of the subfamily are found mainly in Chile and Argentina whereas in North America, representatives are found in Alaska, Canada, all but the northeastern United States (West Virginia and Virginia southward), and in the northern half of Mexico. While some members are found in moist eastern deciduous forests, most are encountered in arid regions of the American West. Representatives may be found below sea level in Death Valley, California, and among the last plants to be seen on nearby Mt. Whitney.

     The subfamily is traditionally divided into two tribes. The trib. Pterostegieae is composed of the annual genus Pterostegia and the perennial genus Harfordia. The latter is restricted to Baja California, whereas Pterostegia is a widespread but often overlooked sprawling plant of California, southern Nevada, southwestern Utah, and Arizona. The trib. Eriogoneae contains far more genera. Next to Eriogonum, the largest in terms of species is Chorizanthe. This genus is composed of some 60 species, the majority of which occur in California. All but nine species are annuals, and the perennials are restricted to Chile.

     Related to Chorizanthe are a series of smaller genera: Mucronea (2 sp.), Systenotheca (1 sp.), Centrostegia (1 sp.), Dodecahema (1 sp.), Aristocapsa (1 sp.), and Lastarriaea (3 sp.). All occur in California; on Centrostegia thurberi and the species of Lastarriaea occur beyond that state. As for the near relatives of Eriogonum there are Dedeckera (1 sp.), Stenogonum (2 sp.), Oxytheca (3 sp.), Acanthoscyphus (1 sp.), Sidotheca (3 sp.), Goodmania (1 sp.), Gilmania (1 sp.) and Nemacaulis (1 sp.). The genus Hollisteria (1 sp.) is somewhat in between Eriogonum and its relatives and those associated with Chorizanthe. Representatives of all of the genera allied with Eriogonum (with the exception of Stenogonum) occur in California. Only a subspecies of Oxytheca dendroidea is found in South America.

     Looking at Eriogonum itself, this genus is subdivided into seven subgenera of unequal size. The largest in terms of numbers of species is the subgenus Eucycla, with approximately 110 species, 104 of which occur north of Mexico. Representatives of this subgenus include such species as E. microthecum, E. corymbosum, E. brevicaule, E. rosense, E. ochrocephalum, E. shockleyi, E. lachnogynum, E. elongatum, E. wrightii, E. racemosum, E. fasciculatum, E. heermannii, E. nudum, E. strictum, E. ovalifolium, and E. saxatile. All are perennial shrubs or herbs, with the latter containing many cespitose or matted expressions. All of the species are found in the American West and on the Great Plains.

     The subgenus Micrantha is composed of two species, Eriogonum annuum and E. multiflorum. They are found on the Great Plains and in Texas, with the former just entering northernmost Mexico. There are tall, erect annuals (or sometimes biennials) with leafy stems. The subgenus Clastomyelon is monospecific with its only species, E. intrafractum, confined to the Death Valley region of California. This is a tall, wand-like perennial with short basal leaves, a leafless stem more than a meter tall with a small inflorescence atop the stem. Curiously, the basal part of the stem dries into napkin-ring like segments.

     Eriogonum subg. Eriogonum is composed of only two species, both confined to the southeastern United States. The original species of the genus is E. tomentosum of southeastern Alabama, Florida, Georgia and south central South Carolina. The other species, E. longifolium, is more widespread, being found from New Mexico to Kentucky, Tennessee and Florida. Here the flowers are on long stipes and are densely covered with long hairs. The stems are erect and leafy, arising from a well-defined taproot. Unlike most members of the genus, the embryo here is straight rather than curved.

     The subgenus Oligogonum is the best known to gardeners for among its 36 species is Eriogonum umbellatum. This remarkable species is found through most of the American West where it may be subdivided into some 40 varieties. Other favorites of the gardener are E. heracleoides, E. thymoides, E. douglasii, E. caespitosum, E. jamesii, E. arcuatum, and E. jamesii. While most occur in the West, E. allenii is confined to the shale barrens of Virginia and West Virginia, being related to E. correllii of northern Texas, E. wootonii of southern New Mexico, and E. arcuatum of the central Rocky Mountains. Eriogonum jamesii is found in the central and southern Rockies and on the Great Plains in portions of southwestern Kansas, extreme western Oklahoma, and Texas. This species occurs in several scattered mountain ranges in Arizona and New Mexico, passing unhindered into northern Mexico. Only one species of subg. Oligogonum is confined to Mexico, E. turneri of San Luis Potosi.

     Members of the subgenus Oligogonum may be distinguished by their stipitate flowers and their mat-forming habit where one finds numerous spreading, leafy caudex branches arising from a taproot (this often obscured due to rooting along the caudex branches). Erect flowering branches then arise from all along the caudex branches. Leaves are therefore basal so that if there are leaves along the stem they are seemingly in whorls near the middle of the flowering branch.

     The last subgenus of perennials is Eriogonum subg. Pterogonum. This is primarily a Mexican group as only six of the eleven species occur north of Mexico, and then two of those (E. atrorubens and E. greggii) just barely cross the border. The most widespread member of the group is E. alatum, a tall, monocarpic perennial of the Great Plains and Rocky Mountains. The flowers in this subgenus lack a stipe (and are thus like the flower of Eucycla, Clastomyelon and Micrantha) but the embryo is straight, unlike any species in those subgenera. The stems are tall, erect, and mostly sparsely leafy with small cauline leaves. Here the fruit, an achene, is large and slightly to obviously winged (as in E. alatum).

     The remaining two subgenera are predominantly annuals. Such plants are generally of little interest to the rock gardener, but for some with more catholic interests, a few are curious members of the genus. Most of those occur in the subgenus Ganysma. This subgenus is composed of some 62 species, of which 53 occur north of Mexico. Here, it is among the handful of perennials that one finds some potentially attractive members for the adventurous gardener. The best known of these perennials is Eriogonum inflatum. This is a plant of the Mojave and Sonoran deserts of the American Southwest, extending northward onto the Colorado Plateau in Utah and Colorado. The inflated stems are what attract most attention. This plant is a first-year flowering perennial, meaning that it produces flowers and fruits its first year. Several closely related species (most with inflated stems) are strictly annual. On the Colorado Plateau one finds E. fusiforme; in the southern coastal and transverse ranges of California is E. hooveri. Eriogonum trichopes is found exclusively on the Mojave and Sonoran deserts; it may or may not produce an inflated stem.

     The more interesting species of Ganysma for the horticultural eye are found in Baja California. Most are restricted in their distribution, and some are rather remote. Foremost is Eriogonum preclarum of the Vizcaino Desert Region of west central Baja. This remarkably beautiful plant has yet to be introduced into cultivation. Both Eriogonum angelense (extremely rare) and E. scalare (much more common) are worthy of consideration, but pale in comparison to E. preclarum. The perennial relates of E. deflexum, namely E. austrinum and E. moranii of Baja California, and the rare and yet-to-be-described E. sarmentosum of southern California might be worthy of limited consideration.

     As for the last subgenus, Oregonium, there is little to recommend. Here one finds several rather weedy species such as E. vimineum and E. baileyi or E. roseum and E. gracile, but curious ones as well such as E. nidularium. Some are weedy on serpentine soils, such as E. luteolum. A few have attractive flowers when viewed close up. Among the more notable here are species like E. maculatum, E. viridescens and E. gossypinum.

     A distinction between Ganysma and Oregonium is somewhat difficult. In general, the involucres of Ganysma are on peduncles with the involucres themselves tending to by smooth surfaced and turbinate to campanulate in shape. The involucres on species of Oregonium are sessile, ribbed and nearly always narrow. The involucres also tend to be appressed to the branch. Unfortunately, there are exceptions to these general features, and a detailed set of features is required to distinguish between the two.

     Numerous species of Eriogonum are now available for the garden. While interest here is mainly those of potential value in the alpine or rock garden (their names are in red), others will be mentioned. For information on the cultivation of Eriogonum, see Alpine Plants of North America by Graham Nicholls (Timber Press, Portland, Oregon; 2002). Here one finds the most detailed horticultural information about this genus now available (see pp. 111-126). While there are some minor difficulties of a taxonomic nature in Graham's book, they are of no importance. As a result, I will follow his treatment of the genus, adding some additional (mainly none alpine species) to the list. Those species for which the information is adequate in his book, I will merely list the name. For others that ought to be considered in the garden, I will make some extended comments. Some corrections, therefore, will be noted. Here I present the name, its authorship, subgenus and a suggested common name. Detailed taxonomic information on the genus is being developed currently for Flora of North America and Intermountain Flora. See http://www.plantsystematics.org/reveal/pbio/eriog/key.html for a web-based treatment of the subfamily.

Eriogonum acaule Nutt. (Eucycla) --- single-stem wild buckwheat.

     See Nicholls, p. 112. Of the several low, matted, cespitose perennials in Eriogonum, this is one of the more lovely. The flowers are in small, capitate clusters arranged in a single involucre atop a short flowering stalk that hardly exceeds the length of the leaves. The species is a true rock garden plant but somewhat slow to grow to reach maximum size (up to 5 dm across). It occurs mainly in southern Wyoming in Albany, Carbon, Fremont, Lincoln, Natrona, Sublette, Sweetwater and Teton counties; it is most commonly seen in Sweetwater, Carbon and Albany counties. The species also occurs in Moffat Co., Colorado. Image

Eriogonum allenii S. Watson (Oligogonum) --- shale barren wild buckwheat

     This is a large, attractive perennial already well-established in cultivation. Its long leaves (to 3 dm), profuse inflorescence of numerous branches covered with bright yellow flowers are its main attractions. Although restricted to the shale barrens of Virginia and West Virginia, it will grow in a variety of habitats when cultivated. Avoid over-watering as the barrens are hot and dry even if they are surrounded by wet deciduous forests. Habit and detail of the flowers

Eriogonum alpinum Engelm. (Oligogonum) --- Trinity wild buckwheat

     The species is restricted to high ridges (2050-2750 m) in the Cory Peak and Mt. Eddy region of Siskiyou and Trinity counties in California where it occurs on serpentine soils. This is listed as an endangered species in the state. Readily recognized by its nearly round leaf-blades and spreading scapes with a whorl of 3-5 foliaceous bracts, capitate inflorescence and bright yellow flowers.

Eriogonum ammophilum Reveal (Eucycla) -- Ibex wild buckwheat

     This is a low, spreading subshrub related to E. nummulare (see below), and as such has little to recommend its use in the garden. It is much more modest than E. nummulare and if one were wishing to have something of this group in the garden, the Ibex wild buckwheat might be worthy attempting. It is considered to be a "sensitive" species by the Bureau of Land Management. Habitat, habit, inflorescences, and flowers and involucres.

Eriogonum androsaceum Benth. (Oligogonum) ---rock-jasmine wild buckwheat

     One can find this species in cultivation infrequently, but it requires more attention. A low, matted perennial typically of subalpine habitats (1700-2650 m) in the northern Rocky Mountains of Alberta, Canada, and northwestern Montana, it is related to Eriogonum flavum but differs significantly in leaf-shape, coloration of its stems and leaves, its pale yellow flowers, and glabrous achenes. In many respects E. androsaceum is the more attractive of the two. As it occurs mainly in national parks in both Canada and the United States, permits are required to obtain seeds.

Eriogonum anemophilum Greene (Eucycla) -- wind-loving wild buckwheat

     In a strict sense this is a plant of limestone outcrops on the West Humboldt Range of Pershing Co., Nevada. The species belongs to a group of closely related, matted perennials of the subg. Eucycla found mainly in the Intermountain West. The species may be characterized by its floccose scapose and cream-white flowers; the leaf-blades vary from elliptic to obovate or even suborbicular in outline. While the plant can be found at higher elevations (ca. 2600 m), most populations now assigned to the species are found much lower (down to 1450 m) where the plants occur on volcanic tuffaceous outcrops on the edges of mountain ranges in central Nevada. See also E. diatomaceum, E. tiehmii and E. rosense var. beatleyae.

Eriogonum annuum Nutt. (Micrantha) --- annual wild buckwheat

     This widely dispersed species of the Great Plains (North Dakota and Montana south to New Mexico, Texas and northern Mexico) may be an annual or a biennial. Tall, erect with a leafy stem and white flowers, it is attractive but can be weedy. Seen occasionally in specialized gardens. inflorescence) and detail of inflorscence

Eriogonum arborescens Greene (Eucycla) --- Santa Cruz Island wild buckwheat

     As an island endemic, Eriogonum arborescens is naturally restricted (where local to occasionally rare) on Santa Cruz, Santa Rosa and Anacapa islands in Santa Cruz and Ventura counties, California. Now widely cultivated and escaped it is found on the mainland from San Mateo Co. south to San Diego Co. where, in places, it has become naturalized. A large, rather decorative shrub, it can be attractive when carefully pruned and maintained. See also E. giganteum.

Eriogonum arcuatum Greene (Oligogonum) --- Baker's wild buckwheat

     Known up to know as Eriogonum jamesii var. flavescens, the var. arcuatum (habit) is the low elevation phase of the species found southeastern Wyoming, Colorado and northeastern Utah south to northern Arizona and northwestern New Mexico mainly in pinyon-juniper or conifer woodlands below 3000 m elevation. Of greater interest to the gardener is the more depressed and compact expression, var. xanthum, restricted to subalpine and alpine ridges and slopes along the backbone of the Colorado Rocky Mountains. Like its low elevation counterpart, var. xanthum was previously assigned to E. jamesii (e.g., Nicholls, p. 117; illustrated but mistakenly identified as E. umbellatum on p. 122). The Ivy League wild buckwheat does well in cultivation and is often seen in rock gardens. In the field it is found up to 4200 m on the higher peaks. Not yet in cultivation is the var. rupicola of Zion National Park, Utah (habit and detail of flowers). It is similar in aspect to var. xanthum, but is confined to sandstone ledges. See also E. flavum and E. wootonii.

Eriogonum aretioides Barneby (Eucycla) --- Widtsoe wild buckwheat

     This is a low, matted, cespitose perennial composed of 20 to 50 compact rosettes forming flattened hummocks on limestone gravel mainly in the Red Canyon Natural Research Area of Garfield and Emery counties, Utah. The inflorescence is tightly appressed to the rosette of tiny leaves (up to 12 mm long and 4 mm wide) and consists of a single involucre with pale or more commonly bright yellow flowers. The flowers are pilose but the achene is glabrous. See also E. shockleyi. Habit and detail of the flowers

Eriogonum argophyllum Reveal (Eucycla) --- Sulphur Hot Springs wild buckwheat

     See Nicholls, p. 112. The Sulphur Hot Springs wild buckwheat is restricted to only a single location on private land in the Ruby Valley of Elko Co., Nevada. The species is considered to be "critically endangered"by the State of Nevada. It is a low, mat-forming perennial similar to Eriogonum kingii (see below) having densely white tomentose leaves, thin, membrane-like involucres with both hairs and glands, and yellow flowers that are sparsely glandular.

Eriogonum bicolor M. E. Jones (Eucycla) --- pretty wild buckwheat

     See Nicholls, p. 112. Few of the low, matted subshrubs rival this wild buckwheat for sheer color and beauty, as the common name implies. The plant is heavily branched becoming up to 3 dm across but only about 8 cm tall. The narrow leaves are slightly exceeded by the flowering stems, but the numerous, rather compact, umbellate to cymose inflorescences position the white to (eventually) red to rose flowers well above the leaves. The perianth lobes are distinctly dimorphic, with those of the outer whorl nearly orbicular, a marked contrast to the narrowly elliptic inner ones. The species is common from Castle Valley and the San Rafael Swells of Carbon and Emery counties, Utah, eastward to Grand Valley of Grand Co., Utah, and Mesa Co., Colorado. It is seen less frequently to the south in Garfield, San Juan, Sevier, and in Wayne counties, Utah. It is somewhat more common in portions of Canyonlands National Park and the Grand Staircase-Escalante National Monument. See also E. ericifolium, E. ripleyi and E. thornei. Habit and detail of the flowers

Eriogonum ´ blissianum Mason (Eucycla)

     This is an established hybrid involving two insular species, E. giganteum var. formosum and E. arborescens. A large shrub with more grace than typical E. arborescens but now infrequently seen in cultivation.

Eriogonum breedlovei (J. T. Howell) Reveal (Eucycla) --- Piute wild buckwheat

     See Nicholls, p. 113. Eriogonum breedlovei is geographically isolated from the rest of the E. ochrocephalum complex being confined to the southern Sierra Nevada. Both var. breedlovei and its counterpart, var. shevockii (Shevock's wild buckwheat), are rare and infrequently encountered on quartzite or granitic outcrops in the southern Sierra Nevada of California in Kern and Tulare counties. The species may be readily recognized by its cymose-umbellate to cymose inflorescence, rigid involucre with glandular hairs (usually), and its whitish to reddish flowers. The plants tends to be loosely matted in the wild, but is more tightly so in cultivation.

Eriogonum brevicaule Nutt. (Eucycla) --- short-stem wild buckwheat

     See Nicholls, p. 113. There is considerable variation within Eriogonum brevicaule, much of which is not worthy of cultivation. For the rock and alpine gardener, efforts should be confined to the low, matted expressions of the species. The low-elevation Bannock wild buckwheat, var. bannockense, resembles E. desertorum (see below); it is found in western Wyoming, southeastern Idaho, northwestern Utah and northeastern Elko Co., Nevada. This is mainly a plant of sandy to shaly or gravelly soils in sagebrush and mountain mahogany communities but can be found in juniper and conifer woodlands between 1800 and 2800 m elevation. A yet-to-be-described variant, the var. inops, occurs on white, clay hills and gullies in the badlands north of the Deep Creek Range in Tooele Co., Utah, and along the eastern border of Elko and White Pine counties in Nevada. High elevation expressions (var. grayi and var. nanum) are found in the Wasatch Range of northern and central Utah, and on scattered desert ranges to the west. The yet-to-be-described var. caelitum of San Pete Co. is the largest of these expressions, and is probably the most worthy of cultivation (see habitat, habit of large plant, habit of small plant, detail of habitat, and flowers). The widespread var. laxifolium is found from Bear River Co., Idaho, south into northern Utah mainly along the western foothills of the Wasatch Range. Nicholls confused this plant with E. desertorum, although his illustration (p. 113) is of E. kingii. Of the more typical expressions of the species, the var. canum (also known as E. lagopus - see habit and flowers) may be worthy of consideration given the hairy flowers and the arid setting of this plant on sandstone ledges in Carbon, Park and Yellowstone counties, Montana, and in Big Horn and Sheridan counties of Wyoming.

Eriogonum butterworthianum J.T. Howell (Eucycla) --- Butterworth's wild buckwheat

     This is a rare and localized species growing in the cracks of Vaqueros sandstone near The Indians in the Santa Lucia Range of Monterey Co., California. It is a low shrub with narrow leaves sheathing up the lower half of the numerous stems. The cymose-umbellate to cymose inflorescence consists of long (up to 6 mm) involucres with ochroleucous to rose flowers. The U.S. Forest Service considers the plant a "sensitive species."

Eriogonum caespitosum Nutt. (Oligogonum) --- matted wild buckwheat

     See Nicholls, p. 113. The species is more widespread than suggested by Nicholls, ranging from southwestern Montana, southern Idaho and southeastern Oregon south into western Wyoming and Utah, Nevada, northwestern Arizona, and eastern California. Plants along the eastern edge of the Sierra Nevada in Long Valley of southern Mono Co., California, form large, dense, whitish-gray mats unlike any other population. In addition to the image of this species on page 114 in Nicholls, there are ones of mature female plants on pages 115 (lower right, misidentified as Eriogonum gracilipes) and page 119 (lower left, misidentified as E. ovalifolium). This is the only member of the subg. Oligogonum in which the "flowering stalk" is actually a long peduncle, that is, there are no subtending bracts below the involucre either immediately so or (as in E. douglasii) near the middle of the upright stem bearing the involucre and flowers. Habit

Eriogonum capistratum Reveal (Eucycla) --- Hitchcock's wild buckwheat

     See Nicholls, p. 114, under E. chrysocephalum. Hitchcock's wild buckwheat, var. capistratum, is rather common in the mountains of central Idaho where it occurs mainly on granitic soils and outcrops from 1975 to 3100 m elevation. This is a low, matted perennial with spatulate to elliptic leaves, a tomentose or glandular scape, a thin, membranaceous involucre with five to seven teeth, and glabrous or sparsely glandular flowers. The var. muhlickii of the Bitterroot and Pintler ranges of western Montana occurs on rocky outcrops in alpine settings. It differs from var. capistratum is having a smaller, more compact habit with both glandular and tomentose (not just tomentose) leaves. The scape is always densely glandular. A disjunct population in the vicinity of War Eagle Peak in the Owyhee Mountains of Owyhee Co., Idaho (see habit), is certainly related to E. capistratum, but its taxonomic disposition is still under consideration. See also E. meledonum and E. verrucosum. Habit, detail of habit and detail of the flowers of var. capistratum; Habit of var. muhlickii.

Eriogonum chrysops Rydb. (Eucycla) --- one-eyed wild buckwheat

     This is a rare species known only from five scattered locations in the Skull Creek area of Malheur Co., Oregon, where it occurs on basaltic or rhyolitic slopes and outcrops in sagebrush communities. The name itself has traditionally been ascribed to populations of E. capistratum and to lesser degrees to E. meledonum and E. verrucosum. This low, matted perennial has oblanceolate to spatulate leaves that are densely white to grayish tomentose on both surfaces, floccose to tomentose scapes, and thin, membranaceous involucres with five teeth. The flowers are yellow and sparsely glandular. The species is listed as a "threatened" species by the state of Oregon. Habitat, habit, detail of habit, and flowers.

Eriogonum cinereum Benth. (Eucycla) --- coastal wild buckwheat

     Coastal wild buckwheat is a large (up to 1.5 m tall and 2.5 m across), grayish shrub with tomentulose stems and leaves. The inflorescences are capitate and restricted to the upper nodes. The white to pinkish flowers are villous. The species is restricted to sandy beaches, coastal bluffs and mesas near the Pacific Ocean of Santa Barbara, Ventura and Los Angeles counties; it also is found on Santa Rosa Island. Although the plant has long been in cultivation, it is only infrequently found in the garden today. Habit and detail of the flowers

Eriogonum clavellatum Small. (Eucycla) --- Comb Wash wild buckwheat

     This is a low, heavily branched, slow growing subshrub with oblanceolate leaves borne in fascicles along the stems. The white flowers are borne in campanulate involucres. The species is confined to heavy clay washes and slopes in saltbush communities in a few, scattered sites in the Four Corners area of San Juan Co., Utah, Montezuma Co., Colorado, and San Juan Co., New Mexico. The Bureau of Land Management considers the plant a "sensitive species" throughout its range. See also E. bicolor and E. pelinophilum.

Eriogonum codium Reveal, Caplow & K. A. Beck (Eucycla) --- Umtanum Desert wild buckwheat

     When initially found on volcanic bluffs overlooking the Columbia River in Hanford Research National Monument in Benton Co., Washington, the population was large and vigorous. Since then, wild fire has destroyed a significant number of individuals so that the species is now considered a candidate for federal listing under the Endangered Species Act; it is already so listed by the state of Washington. The species may be distinguished by its cymose-umbellate to umbellate inflorescence, lemon-yellow flowers, and thinly tomentose flowers and achenes. Ongoing efforts to cultivate the species have shown the plant to be slow growing, and in the wild, a newly established plant can take up to seven years before it flowers.

Eriogonum coloradense Small (Eucycla) --- Colorado wild buckwheat

     The Colorado wild buckwheat is a high elevation (23800-3900 m) expression derived from E. lonchophyllum (see below) that is restricted to the backbone of the central Colorado Rocky Mountains in Chaffee, Park, Gunnison and Sanguache counties; it is considered to be a "sensitive species." It differs from E. lonchophyllum by its low, matted habit and capitate inflorescence.

Eriogonum compositum Douglas ex Benth. (Oligogonum) --- arrow-leaf wild buckwheat

     See Nicholls, p. 114. Little needs to be added to what Graham Nicholls has penned. The var. compositum (see habit and flowers) has long been in cultivation (since about 1830), tends to be both leggy and rather trashy, but its cream (see image) to yellow flowers, large leaves and inflorescences with an abundance of flowers have overcome the perceived faults. Overall, this a larger and more robust plant than Eriogonum umbellatum. Of the three varieties, the var. leianthum is the most attractive in the garden. It is seen rather often in European gardens.

Eriogonum congdonii (S. Stokes) Reveal (Oligogonum) --- Congdon's wild buckwheat

     Few shrubs of the genus Eriogonum deserve more attention by the gardener than this one. While not something that would be appropriate for the rock or alpine garden, this spreading or even matted subshrub to small shrub could find a place as a specimen plant, especially if featured. By selecting plants that are bright green and glabrous, especially on the stems, branches, and the adaxially surface of the otherwise olive-green leaves, would be the first step. The numerous, large (to 6 mm long) bright sulphur-yellow flowers are just an additional bonus. The plant has a restricted distribution in the mountains of central northern California (southern Siskiyou and northern Trinity cos.). In the field, Congdon's wild buckwheat is often spectacularly set off against the greenish-black of the serpentine outcrops where it occurs naturally. Habit, detail of habit, and detail of the flowers

Eriogonum contortum Small ex Rydb. (Eucycla) --- Grand Valley wild buckwheat

     This species is restricted to the Grand Valley of eastern Grand Co., Utah, and western Mesa Co., Colorado, where it is found on Mancos Shale flats and slopes in saltbush communities at 1300-1650 m elevation. The narrow leaves are up to 2.5 cm long, bright green and revolute (the revolute margins usually hide the white tomentose lower surface). The floccose to glabrous stems and branches are bright green and boldly set off by the bright yellow flowers. The Grand Valley wild buckwheat is related to E. acaule (see above) and thus a member of the E. brevicaule complex. The plant is rarely cultivated but would make a worthy addition to the rock garden as a low, compact subshrub that typically is no more than 1 dm tall. Habitat, habit, detail of habit, and flowers in fruit.

Eriogonum correllii Reveal (Oligogonum) --- Correll's wild buckwheat

     Only a few, scattered populations are known of this uncommon species restricted to Armstrong, Briscoe, Floyd, Foard, Hardeman and Knox counties in northern Texas where it occurs on clayey flats and mounds in mesquite communities. It is a robust, herbaceous perennial allied with E. allenii (see above) and E. wootonii (see below) in the E. jamesii complex. The flowers are bright yellow and the leaves are large (up to 15 cm long and 3.5 cm wide) that are floccose to glabrous and green on the adaxially surface, but densely white-tomentose abaxially.

Eriogonum corymbosum Benth. (Eucycla) --- crisp-leaf wild buckwheat

     Continuing study of this shrub continues to reveal taxonomic problems that are not easy to resolve. The var. corymbosum is now defined to include four phase (the var. corymbosum, var. erectum - see habit, var. divaricatum and subsp. durum - see (habit, inflorescence and flowers) each of which differs slightly but consistently with more or less discrete ranges (southwestern Wyoming, eastern Utah, western Colorado and northern Arizona). The var. aureum (golden wild buckwheat, see habitat, habit, and detail of habit) is restricted to the Shivwits Hills near Castle Cliffs in Washington Co., Utah, this being a yellow-flowered (or rarely cream-colored - see habit) phase with glabrous (or nearly so) inflorescences. The var. glutinosum (sticky wild buckwheat, habitat, habit, inflorescence) is now defined as a large, roundish shrub with numerous, mainly yellow (or infrequently white) flowers of saltbush, blackbrush and sagebrush communities on the Colorado Plateau in southern Utah and northern Arizona. A new variety, yet to be described, is var. nilesii (Niles' wild buckwheat; see habitat, habit, inflorescences, detail of inflorescences , leaves, and flowers), another large shrub with yellow (rarely white; see image) flowers and densely white lanate to tomentose leaves. This plant, confined to the Mojave Desert in the Las Vegas and Muddy Mountain regions of Clark Co., Nevada, is far less attractive than var. glutinosum, although with proper pruning the shrub might be formed into something worthy of the garden. Of the remaining varieties, only the velvety (var. velutinum, habit) and the orbicular-leaf (var. orbiculatum) wild buckwheats (habit) might be worthy of serious cultivation. These are large shrubs that form rounded mounds that, when fully mature, are covered with white flowers over green to white leaves. Both of these varieties occur on the Colorado Plateau, although the former extends its range well into north central New Mexico.

Eriogonum crocatum A. Davidson (Eucycla) --- saffron wild buckwheat

     As one of the more widely cultivated species of Eriogonum, this species has attracted numerous enthusiasts. Interestingly, the species is rare in the wild, being found only from the Conejo Grade area of the Santa Monica Mountains in Ventura Co., California. As a small, erect to spreading shrub or subshrub, it is rarely found in alpine or rock gardens, being preferred as an edge or corner species where its white-lanate to tomentose leaves, stems and branches are brilliantly offset by its numerous bright yellow flowers. Unlike most species of the genus, the saffron wild buckwheat retains a degree of form and color even in the vegetative state. Like the related E. saxatile (see below), this species bears flowers with a winged stipe, an unusual feature of the subg. Eucycla.

Eriogonum cronquistii Reveal (Eucycla) --- Cronquist's wild buckwheat

     This rare species, confined to Bull Mountain in the Henry Mountains of Garfield Co., Utah, might be worthy of cultivation. It is a low, spreading perennial with crenulate leaves, subcapitate to cymose inflorescences, and white flowers. As a species of granitic talus slopes and outcrops, it is probably slow growing.

Eriogonum crosbyae Reveal (Eucycla) --- Crosby's wild buckwheat

     The definition of this species has been expanded to include a series of widely scattered populations of low, matted, herbaceous perennials with weakly erect, tomentose scapes bearing capitate inflorescences of campanulate, weakly rigid involucres with five teeth. The yellow flowers are glabrous. The plant is found on low elevation (12255-2100 m) white tuffaceous volcanic outcrops, flats, washes and slopes in southern Harney (Guano and Coleman valleys) and Lake (Fish Fin Rim) counties, Oregon, and in northern Washoe (mainly Calico Mountains and in the Granite Range) and Humboldt (Virgin Valley) counties, Nevada. The plant is considered a "sensitive species" by the Bureau of Land Management in both states. Habitat, habit, and flowers.

Eriogonum cusickii M. E. Jones (Eucycla) --- Cusick's wild buckwheat

     The species is a low, matted perennial allied to Eriogonum prociduum in the E. ochrocephalum complex, and thus its umbellate-cymose to cymose inflorescence quickly distinguishes it from its near relative. The bright green and glabrous leaves, stems and branches quickly distinguish the species as well; the flowers are yellow and glabrous. The plant is found on low elevation (1300-1500 m) sandy, volcanic flats in mixed grassland and sagebrush communities, and in montane conifer woodlands in scattered portions of Deschutes, Harney, Klamath and Lake counties of Oregon. Habit and detail of the habit

Eriogonum desertorum (Maguire) Maguire ex R.J. Davis (Eucycla) --- Great Basin desert wild buckwheat

     A sharp distinction between this species and Eriogonum brevicaule var. bannockense is difficult, and the taxonomic position of E. desertorum remains to be resolved. As here defined, this is a low to mid-elevation (1500-2950 m) cespitose, matted perennial with oblanceolate to elliptic or ovate leaves that are variously pubescent. The scape may be floccose to tomentose, and the weakly rigid involucres have five to eight teeth. The yellow flowers are glabrous. The plant is confined to gravelly or silty to clayey flats, slopes and ridges on soils mainly derived from a limestone substrate in central and eastern Elko Co., Nevada, and western Box Elder Co., Utah. Upper elevation plants with broad leaf-blades and a shorter, more compact habit were separated as E. lewisii, but this distinction is not now maintained. See also E. crosbyae. Habit and details of the habit.

Eriogonum diatomaceum Reveal, J. Reynolds & Picciani (Eucycla) --- Churchill Narrows wild buckwheat

     This recently described species is restricted to white chalky slopes in saltbush communities in the Churchill Narrows south of Fort Churchill State Park in Lyon Co., Nevada. The species is similar to both Eriogonum anemophilum (see above) and E. tiehmii (see below), differing in its elliptic leaves, tomentose scape, an inflorescence composed of five to ten, rigid, and tomentose involucres. Like its near relatives, this is a low, matted perennial with creamy-white flowers. The plant is considered a "sensitive species" by the state of Nevada. See this detailed presentation.

Eriogonum diclinum Reveal (Oligogonum) --- Jaynes Canyon wild buckwheat

     See Nicholls, p. 114. Eriogonum diclinum is a low, spreading, matted perennial with distinctly different male and female expressions. The male plants tend to have capitate inflorescences of small, often pale yellow to yellow flowers that wither and become ratty looking with age. The female plant, on the other hands, starts out with a capitate inflorescence of mostly yellow flowers, but after pollination, and thus as the achenes mature, the obscure branches of the inflorescence elongate and the flowers become rose to red in color. The leaves (and thus the mats) are surprisingly attractive throughout the year, making this a potentially useful ground cover plant for small areas. The species is found in the Siskiyou and Trinity mountains of California (Siskiyou and Trinity cos.) and Oregon (Jackson and Josephines cos.). It is confined to serpentine flats and slopes. See also Eriogonum marifolium. Habit of male and female plants growing intermixed; habit of the male plant and detail of the male flowers; habit of a female plant and detail of the female flowers.

Eriogonum douglasii Benth. (Oligogonum) --- Douglas' wild buckwheat

     See Nicholls, p. 114. As now defined, Eriogonum douglasii is subdivided into a series of varieties. In a strict sense the var. douglasii is low, mat-former with spatulate leaves; it is found mainly in the Blue and Wallowa mountains of southeastern Washington and northeastern Oregon. It is also in the mountains of Adams and Idaho counties, Idaho, and just inside the Intermountain Region in Malheur Co., Oregon. Out on the scablands of eastern Washington and north central Oregon east of the Cascade Range is a sprawling subshrub with narrow, oblanceolate leaves. This expression is treated as var. sublineare (see habitat, habit, leaves and inflorescences, and flowers. A clear distinction between this phase and var. douglasii is not sharp in portions of Oregon, and some plants of E. sphaerocephalum var. halimoides are often confused with var. sublineare. In northeastern California, western Nevada, and extreme south central Oregon is the yet-to-be-described var. meridionale. It is this phase of the species that is most commonly seen in cultivation (see habitat, habit, and inflorescence). An expression with larger flowers will be described in the near future as var. elkoensis. It is known only from the Sunflower Flat area of northwestern Elko Co., Nevada. See E.sphaerocephalum and E. twisselmannii.

Eriogonum effusum Nutt. (Eucycla) --- spreading wild buckwheat

     Eriogonum effusum is a large, diffusely branched, spreading shrub of the Great Plains and Rocky Mountains, being found from southwestern South Dakota and southeastern Wyoming south through southwestern Nebraska into eastern Colorado and northeastern New Mexico. Contrary to statements made by some, the species is absolutely distinct from E. microthecum (see below), and no intermediates are known as their ranges do not overlap. The spreading wild buckwheat is infrequently seen in cultivation but deserves more attention for with careful pruning the shrubs could be made rather floriferous. See. E. helichrysoides.

Eriogonum elatum Douglas ex Benth. (Eucycla) --- tall wild buckwheat

     This is an erect herbaceous perennial with large, green leaves, an open inflorescence with green and glabrous or graying and villous stems, and white flowers. The stout, woody taproot is easily transplanted, and the species does well in cultivation under a variety of conditions. The species is widely distributed on dry, often grassy slopes from eastern Washington south to northern and eastern California and northern Nevada.

Eriogonum elongatum Benth. (Eucycla) --- long-stem wild buckwheat

     The plant is a tall, erect to slightly spreading perennial herb with numerous cauline leaves often arranged in fascicles. The long, whip-like branches allow the plant to grow in windy areas, and the large, stout taproot assures its easy of transport and survival. Unlike E. elatum, E. elongatum is much less attractive in the garden as it tends to be rather trashy. However, E. elongatum tends to flower in fall of the year, whereas E. elatum flowers from late spring to late summer. Both species have long been in cultivation, but neither is particularly attractive. Habit and detail of a flowering branch.

Eriogonum encelioides Reveal & C. A. Hanson (Eucycla) --- brittlebrush wild buckwheat

     This large shrub belongs to the Eriogonum giganteum complex, and as such is worthy of cultivation. Unfortunately, it is localized in the western portion of the Vizcaino Desert in central Baja California, Mexico, and thus difficult to obtain. Nonetheless, the species ought to do well in cultivation. Habit, inflorescence, and flowers.

Eriogonum ericifolium Torr. & A. Gray (Eucycla) --- heather-leaf wild buckwheat

     As here defined, this is a low, spreading and matted subshrub with revolute, linear leaves and a umbellate-cymose inflorescence composed of turbinate, floccose involucres and white flowers. The plant is rare and localized in the Verde River Valley of Yavapai Co., Arizona. Although recently reported from Pima Co., this population and a similar one in Cochise Co. will be the subject of field work in October as it appears they are distinct from the Verde River plants and may well represent a new entity. See also Eriogonum pulchrum and E. thornei.

Eriogonum erubescens Reveal & J. Knorr (Eucycla) --- blushing wild buckwheat

     At the moment this seemingly new species is on hold pending further study. Known presently from the Scott Bar Mountains in Siskiyou Co., California, it is possible another population has been found to the west. Furthermore, older collections of the closely related Eriogonum ursinum (see below) gathered by forest ranges some eighty years ago demonstrate that that species is not confined solely to the Sierra Nevada of California. The blushing wild buckwheat has longer involucres and flowers and a less complex inflorescence. Final deposition of this plant, as to rank, will be made in the winter of 2004-2005. Habitat, habit, detail of the habit, inflorescence, and flowers.

Eriogonum exilifolium Reveal (Eucycla) --- drop-leaf wild buckwheat

     The species is a low, matted perennial with linear to linear-oblanceolate, revolute leaves up to 6 cm long. The leaves and stems tend to be a dark green but may have a slight grayish tint due to a floccose or sparse tomentose condition in some. The bright white flowers are a contrast against the green vegetation and the red soil where the plant is found seen. It occurs in Carbon and Albany counties of Wyoming, and in Grand, Jackson and Larimer counties in Colorado. It is allied to Eriogonum lonchophyllum (see below) and E. coloradense (see above). Habit, detail of habit

Eriogonum fasciculatum Benth. (Eucycla) --- California buckwheat

     The low matted subshrub to large shrub is, in some of its forms, a dominate member of the chaparral communities in California; elsewhere the plant is common on the Mojave Desert of southern California, Nevada and southwestern Utah, and in portions of western Arizona. It is also common in Baja California. Various forms of the species have been in cultivation since the early 1800s. The Mojave Desert California buckwheat (var. polifolium; habit) is the most widespread of the recognized variants. Some of the populations found on limestone outcrops are composed of compact shrubs that might be worthy of cultivation. The yellowish-green phase known as the Sonoran Desert California buckwheat (var. flavovirde; habit) is more attractive, however. The most commonly cultivated phase is the coastal California buckwheat (var. foliolosum, see Nicholls, p. 115; habit). This is a large shrub (up to 1.5 tall and 2.5 m across) that is found mainly in the coastal ranges of California and Baja California. Less often seen, but certainly the most interesting of all is var. fasciculatum. This is a low, spreading, often glabrous and dark green subshrub (rarely a low shrub) found along coastal bluffs and mesas near the Pacific Ocean from San Luis Obispo Co. southward. Some expression in northern Baja California would seem to worthy of selection as a low, spreading mat-former in the arid or rock garden.

Eriogonum fastigiatum Parry (Eucycla) --- San Antonio del Mar wild buckwheat

     This Baja California, Mexico, endemic is found in coastal sage communities where it forms low, compact mats of numerous, small green leaves and scattered clusters of white flowers. Habit and flowers.

Eriogonum flavum Nutt. (Oligogonum) --- alpine golden wild buckwheat

     In addition to Piper's wild buckwheat (var. piperi; habit, inflorescence and flowers) discussed by Nicholls (p. 115), the var. flavum (see habitat, habit, inflorescences, and flowers) itself is worthy of consideration in the garden. The var. flavum is a much more compact plants, and generally shorter. Because of its well-formed taproot, the plant can be easily transplanted; it does well in a variety of conditions. The var. piperi is the western phase of the species, being found mainly in the foothills and mountains of Montana, Idaho, and eastern Washington south into northeastern Oregon and northwestern Wyoming. In Canada, the variety occurs in southern Alberta and British Columbia. The var. flavum tends to be a plant of the Great Plains, but does extend into the mountains in Alberta and Montana. Thus, var. flavum ranges from Alberta, Saskatchewan and southwestern Manitoba south to northeastern Colorado and western Nebraska. The var. xanthum, mentioned by Nicholls, is treated here under Eriogonum arcuatum (see above). Care must be taken in southeastern Wyoming and along the front range of the Rocky Mountains in north central Colorado to differentiate between E. flavum and E. arcuatum.

Eriogonum giganteum S. Watson (Eucycla) --- St. Catherine's lace

     Among the insular endemics belonging to Eriogonum, this is the most widely cultivated member, and today, along coastal California, it is now widely naturalized. Three varieties are recognized, and all three may be found in cultivation. The var. giganteum (habit and inflorescence) is a large shrub in the wild, some individuals on Santa Catalina Island being 3.5 m tall. Its oblong to ovate leaves and open inflorescence distinguishes it from the San Clemente Island endemic, var. formosum (inflorescence). The rare variety from Santa Barbara and Sutil islands, var. compactum is mostly restricted to botanical gardens. The introduction and naturalization of this species (and E. arborescens, see above) onto the mainland of California is resulting in introgression of these species with coastal natives, the long-term impact of these being unknown. Every effort should be made to remove the insular species from along the coast so as to prevent their genetic contamination with other species.

Eriogonum gilmanii S. Stokes (Eucycla) --- Gilman's wild buckwheat

     This rare species is not known to be in cultivation, but is certainly worthy of introduction. It is restricted to limestone gravel and rocky outcrops in the Cottonwood, Last Chance and Panamint mountains of Inyo Co., California. It has strongly dimorphic flowers, a feature shared by Eriogonum ovalifolium. The outer perianth-lobes of the off-yellow flowers are orbicular in outline and inflated, with a large reddish midrib, the combination making this one of the more attractive flowers in the genus. Its habit is that of a low, pulvinate perennial with short (up to 4 mm), elliptic leaves and a cymose-umbellate inflorescence on spreading branches. Habit and flowers.

Eriogonum gracilipes S. Watson (Eucycla) --- White Mountain wild buckwheat

     See Nicholls, p. 115. This low, cespitose, matted perennial have leaves up to 2 cm long and 6 mm wide; the leaves are densely white-tomentose abaxially but less and often somewhat greenish adaxially. The capitate inflorescence is on a short (to 8 cm) scape, and the glabrous flowers are white to rose in color. The species occurs on the eastern slope of the Sierra Nevada as well as the White Mountains of Mono and Inyo counties, California, and just enters Esmeralda Co., Nevada. See also Eriogonum holmgrenii. Habit and inflorescence.

Eriogonum grande Greene (Eucycla) --- Pacific Island wild buckwheat

     The large, much branched and often matted herbaceous perennial or subshrub is subdivided into four varieties, three of which are confined to off-shore island along the California coast. While both var. grande (of Santa Cruz, San Miguel, Santa Catalina, Anacapa, and San Clemente islands) and the St. Nicholas wild buckwheat (var. timorum of San Nicolas Island) are infrequently seen in cultivation, the most common expression in gardens in the red-flowered Pacific Island wild buckwheat, var. rubescens. The variety occurs naturally on San Miguel, Santa Cruz and Santa Rosa islands, and while not yet naturalized along the California coast, it is likely this will occur eventually. On some of the near-shore island of Baja California, and just on the mainland, one finds the var. testudinum (habit and inflorescence). The species is closely related to Eriogonum nudum (see below).

Eriogonum gypsophilum Wooton & Standl. (Eucycla) --- Seven River Hills wild buckwheat

     Being a federal protected endangered species, access to seeds is limited for this bright green herbaceous perennial with equally bright yellow flowers found on low gypsum hills in Eddy Co., New Mexico. The cordate to truncate, glabrous leaves and cymose inflorescences are distinctive.

Eriogonum heermannii Durand & Hilg. (Eucycla) --- Heermann's wild buckwheat

     Of the many varieties of this species, most of which are large, rounded shrubs of the arid Great Basin and portions of California (as in var. humilius; see an image), only the grooved wild buckwheat, var. sulcatum, is worthy of serious consideration by the rock gardener. This is a spreading, highly branched subshrub with greenish (usually), compact stems and numerous, densely compacted, furrowed inflorescence branches topped by small, yellowish-white flowers. It is a plant of dry limestone cliffs and outcrops in saltbush, blackbrush, sagebrush, and mountain mahogany communities, and in scrub oak and pinyon-juniper woodlands. It is encountered between 700 and 2700 m elevation in the desert ranges of southeastern Inyo and northeastern San Bernardino counties, California, Clark and southern Lincoln and Nye counties, Nevada, and in Washington Co., Utah. In Arizona, the plant occurs in northern Mohave Co. and just over the line into northwestern Coconino Co. Given its habitat, this may be difficult to grow. Also, any damage to the mature plant is slow to recover. For this variety, see habit, and flowers.

Eriogonum helichrysoides (Gand.) Rydb. (Eucycla) --- stawflower wild buckwheat

     This plant is more widely known in the currant systematic literature as Eriogonum effusum var. ramosissimum Benth., but continued research on the genus has shown E. helichrysoides and E. effusum are both geographically and morphological distinct, and species rank, as suggested by Per Axel Rydberg in 1917, is the more appropriate rank. This is a diffusely branched, spreading, dark green shrub up to about 4 dm tall and 8 dm across. Its leaves are linear to linear-oblanceolate, and thus much narrower than anything seen in E. effusum. The strawflower wild buckwheat is restricted to clay slopes or chalky limestone outcrops in grassland communities of southwest Kansas in Ellis, Gove, Lane, Logan, Scott and Trego counties. Habitat, habit, and detail of habit

Eriogonum heracleoides Nutt. (Oligogonum) --- parsnip-flower wild buckwheat

     See Nicholls, p. 115. In addition to its range in the Rocky Mountains, the species is also found in scattered desert ranges of northwest California (Modoc Co.), southeastern Oregon, southern Idaho and northern Nevada, and in portions of western Utah. Plants in the Pacific Northwest traditionally have been separated as the var. angustifolium because of their narrow leaves, but this distinction seems unworthy of retaining as such plants are found in scattered populations elsewhere. Still, this feature is not seen in any of the populations in Colorado, Montana, Utah or Wyoming, the traditional home of var. heracleoides. The distinguishing feature of var. heracleoides is the presence of a whorl of leafy bracts midlength along the flowering stem. This is missing in the var. leucophaeum, mistakenly called var. minus by Nicholls. Such plants are found mainly in grassland communities of eastern Washington and west central Idaho, although scattered populations are know further to the east in mountain valleys of central Idaho. There is considerable variation in the overall color of the plant, and in the amount and color of the tomentum of the vegetation. Populations of var. heracleoides from the higher elevations of the Cascade Range in central Washington (where it can occur in the subalpine) are composed of depressed individuals with short, sprawling stems and inflorescences. Such plants would be attractive in the rock garden, unlike the much more open and sprawling, lower elevation plants. Image of the habit.

Eriogonum hirtellum J. T. Howell & Bacig. (Oligogonum) --- Klamath Mountain wild buckwheat

     The Klamath Mountain wild buckwheat is one of the more attractive members of the genus, and certainly worthy of cultivation. Unfortunately, this low, spreading, herbaceous perennial with the bright green leaves, stems and branches is not one that would attract the interest of the rock gardener as the plant can be up to 3.5 dm tall. Still, the large mats (up to 6 dm across) of closely arranged leaves does make a colorful ground cover as the hirtellous to glabrescent leaves change from a green to red as the season changes from late summer to fall. Here to one finds a subcapitate cluster of numerous involucres and bright yellow flowers that also mature to a red, albeit rusty, hue in the fall. This is a plant of serpentine slopes and outcrops in oak and conifer woodlands of the Klamath Mountains in Siskiyou Co., California, and just over its boundary in Del Norte Co. The plant is considered to be a "sensitive" species by the Bureau of Land Management. See Eriogonum latens (below). Habitat, habit, and flowers.

Eriogonum holmgrenii Reveal (Eucycla) --- Holmgren's wild buckwheat

     See Nicholls, p. 116. This species is similar to Eriogonum gracilipes (see above) but much more restricted in its distribution, being confined to the Snake Range of White Pine Co., Nevada.

Eriogonum incanum Torr. & A. Gray (Oligogonum) --- frosted wild buckwheat

     See Nicholls, p. 116. As implied by both its common and scientific names, the leaves of this species are grayish tomentose, giving the loose mats a different hue from its near relatives. The species is found at elevations in the southern Sierra Nevada up to 4000 m although the species occurs from Washoe Co., Nevada, and Placer and El Dorado counties south to Tulare and Fresno counties in California. Remember, this is a dioecious plant, and the two sexes are morphologically different. See also Eriogonum marifolium.

Eriogonum jamesii Benth. (Oligogonum) --- antelope sage

     See Nicholls, p. 116. While the var. jamesii is largely confined to the central Rocky Mountains of Colorado as stated by Nicholls, in fact this expression ranges well to the south and east on the grasslands of northern New Mexico, extreme western Oklahoma (Cimarron Co.) and in northern and western Texas at elevations as low as 1000 m. On the chalky hills in Logan and Scott counties, Kansas, one finds the var. simplex (Kansas antelope sage) so named because its inflorescence is reduced (typically) to a single umbel, unlike the var. jamesii and the var. undulatum. The latter, or wavy-margined antelope sage, is found mainly on limestone slopes in the mountains of southernmost Arizona, New Mexico and Texas. It differs from the others in having leaves with undulate and frequently crisped leaf margins. This expression is rather more sprawling than var. jamesii. None of the varieties of this species is as attractive, as a rock garden plant, as the expressions of E. arcuatum (see above) listed in Nicholls under the names E. jamesii var. flavescens and var. xanthum.

Eriogonum jonesii S. Watson (Eucycla) --- Jones's wild buckwheat

     It is doubtful this spreading subshrub with dense white to brownish tomentum would be of much interest to the rock gardener as the large, cordate leaves that sheath the lower portion of the often sprawling stems, and the brownish-white flowers are not all that attractive. However, it is an uncommon plant, being restricted to limestone or sandstone washes, flats and outcrops mainly in blackbrush communities of Coconino Co., Arizona, with scattered populations just entering Mohave and Navajo counties, and it may be a challenge to some to find an appropriate place in the garden for such a plant.

Eriogonum kelloggii A. Gray (Oligogonum) --- Douglas' wild buckwheat

     See Nicholls, p. 117. Graham Nicholls is correct, this is a species that could cause one to "drool over," but it is well to remember that it is exceedingly rare and listed as an endangered species by the state of California, and the Bureau of Land Management considers it a species of "special" status.

Eriogonum kennedy Porter ex S. Watson (Eucycla) --- Kennedy's wild buckwheat

     See Nicholls, p. 117. In addition the three expressions mention by Nicholls, the Purpus wild buckwheat (var. purpusii) must be mentioned. Like the vars. kennedyi, austromontanum and alpigenum of the transverse ranges of California (Mt. Pinos, San Gabriel and San Bernardino mountains), the var. purpusii is a low, matted perennial, but here the tomentum is a bright white and much more dense. Furthermore, the flowers are of an attractive bright white, rather than the dull white to brownish-white of the others. The var. purpusii is found on the eastern slope of the Sierra Nevada and on the White Mountains on sandy flats and slopes (often of a volcanic origin) mainly in pinyon, juniper and Jeffrey pine woodlands of Inyo and Mono counties, California, and in Esmeralda Co., Nevada. Furthermore, this is much more common than any of the more southern expressions, and much prettier in the field.

Eriogonum kingii Torr. & A. Gray (Eucycla) --- Ruby Mountains wild buckwheat

     This is one of the more attractive of the rock garden species belonging to the genus Eriogonum. The species is confined to limestone flats, slopes and outcrops in Granite, Ruby and East Humboldt ranges of Elko Co., Nevada, and the Cherry Creek Range of northern White Pine Co. where it occurs in mixed grassland and high elevation sagebrush communities, and in subalpine conifer woodlands from 2400 to 3300 m. The species is divided into two varieties, the high elevation var. kingii (geographically described above) and its low elevation counterpart tentatively name var. albatum. The latter differs in having a more attractive white-tomentose leaf (rather than greenish-tomentose) and a cream-colored flower that can be pale yellow or rarely yellow. Flowers of var. kingii tend to vary from a greenish-yellow to a pale yellow. The Elko Hills wild buckwheat is known only from granitic slopes in the Snake Mountains, Elko Hills and Dixie Hills in Elko Co., Nevada. Nicholls, p. 113) illustrate E. kingii, mistakenly calling it E. brevicaule var. laxifolium.

Eriogonum lachnogynum Torr. & A. Gray (Eucycla) --- wooly-cup wild buckwheat

     It is the densely white pubescent flowers with their bright yellow interior that makes this plant attractive to the gardener. The widespread var. lachnogynum is found mainly on sandy to gravelly (often calcareous) or shaly to clayey or gypsum flats and washes in grassland, creosote bush, or mesquite communities, and in pinyon and/or juniper woodlands in northeastern Arizona, southern Colorado, southwestern Kansas, northern New Mexico, western Oklahoma, and northern Texas. This is a plant is a long (1-2 dm) flowering stem. Much more to the liking of the rock gardener is the depauperate var. serra (grandmother's wild buckwheat) of Apache and Navajo counties, Arizona, and McKinley Co., New Mexico. Here the flowering stem is less than 2 cm long, and the whole plant forms dense, cespitose mats up to 1.5 dm across. Currently, the var. serra is known only from a few, scattered locations, some of which are on protected federal lands.

Eriogonum lancifolium Reveal & Brotherson (Eucycla) --- lance-leaf wild buckwheat

     This member of the Eriogonum corymbosum complex is confined to heavy clay flats and rolling slopes near Wellington in Carbon and Emery counties, Utah. Like others of the complex, this is a large, spreading, diffusely branched shrub (to 8 dm tall and 10 dm across) but with a distinctive, bright, grayish tomentum, unlike the more brownish hue found in most of the other species. If properly pruned and maintained, this shrub should make a form a tight crown that would be covered with numerous white flowers. Unfortunately, and like others of the complex, the shrubs are not attractive when lacking flowers, although in the case of the lance-leaf wild buckwheat it is less obnoxious. Habit.

Eriogonum latens Jeps. (Oligogonum) --- Inyo wild buckwheat

     Like its northern counterpart, Eriogonum hirtellum of the Klamath Mountains, this is a compact, herbaceous perennial with bright green, pilose leaves and flowering stems. Here too one finds a long, naked stem so that the plant can be up to 5 dm tall, but unlike the Klamath Mountain wild buckwheat, the mats of E. latens are not much more than 2 dm across. The involucres and cream to pale yellow flowers are arranged in dense clusters atop the stems. This plant is found on sandy to gravelly granitic slopes and ridges in sagebrush communities, and in montane to subalpine conifer woodlands in the White Mountains on the border of California and Nevada (in Esmeralda Co.), and along the eastern slope of the Sierra Nevada in both Inyo and Mono counties. An isolated population occurs on Waucoba Mountain in the Inyo Mountains.

Eriogonum latifolium Sm. (Eucycla) --- seaside wild buckwheat

     Being a species of the coastal bluffs overlooking the Pacific Ocean from Curry Co., Oregon, to San Luis Obispo Co., California, seaside wild buckwheat was gathered by some of the earliest naturalists who visited western North America. A low, much branched herbaceous perennial to subshrub capable of being as much as two meters across, with dense tomentum that varied from white to tan or rust, with capitate to umbellate or cymose inflorescences of white to pink or rose flowers, it was quickly introduced into cultivation. It has been a favorite for nearly 200 years. With careful tending, this can be an attractive plant for in coastal settings it can be in flower throughout the year. It appears to be easy to grow and maintain, but it does require a lot of care to prevent it becoming unattractive. If selections were made for a low, mat-forming cultivar, this could be an even more popular plant for the gardener. Habitat, habit, detail of habit, and flowers.

Eriogonum leptocladon Torr. & A. Gray (Eucycla) --- sand wild buckwheat

     The slender-stemmed, grayish to greenish desert shrub of sandy flats and dunes on the Colorado Plateau of Utah, Colorado, Arizona and New Mexico is Eriogonum leptocladon. There are three varieties: the white-flowered, gray-stemmed var. ramosissimum (San Juan wild buckwheat; see habitat and habit), the yellow-flowered, greenish-gray stemmed var. leptocladon (habit and inflorescences), and the white-flowered, bright green or gray (but glabrous) stemmed var. papiliumculi (butterfly wild buckwheat; see the inflorescens). The first is the most common. None is particularly attractive as the sprawling habitat of the species does not lend itself to most garden settings. However, the species does well in an arid, sandy habitat, appears to grow rapidly, and adjusts itself to ever-moving sand. When seen in dense masses, which can be seen on the San Rafael Desert of Utah, the plant is most attractive being well set-off from the red sand of this desert.

Eriogonum leptophyllum (Torr.) Wooton & Standl. (Eucycla) --- slender-leaf wild buckwheat

     Few of the large, perennial shrubs related to Eriogonum microthecum and E. corymbosum would make attractive plants in the garden if left unattended. This one might be an exception for here is a naturally round-shape shrub with dense, congested inflorescences on numerous, thinly pubescent, green stems. The white flowers tend to be dramatically displayed against the tall (to 8 dm), wide (to 12 dm) mass of the dark green shrub. Here, the leaves are linear to linear-oblanceolate in shape, and rather long (up to 6 cm) on short (mostly less than 1 mm) petioles. The species is found mainly on southern Colorado Plateau in San Juan Co., Utah, and adjacent Montezuma Co., Colorado, southward into Apache Co., Arizona, and in northwestern New Mexico (Bernalillo, McKinley, Rio Arriba, Sandoval, San Juan, Santa Fe, Taos and Valencia cos.). The plant is also encountered, albeit rarely, in Coconino and Navajo counties, Arizona. It occurs on clay flats, slopes and outcrops in mainly mixed grassland and sagebrush communities, and in pinyon-juniper woodlands. Its large size, compact growth, and the bright green of its vegetative growth readily distinguishes this from E. microthecum var. simpsonii (see below).

Eriogonum libertini Reveal (Oligogonum) --- Dubakella Mountain wild buckwheat

     See Nicholl (p. 117).

Eriogonum lobbii Torr. & A. Gray (Oligogonum) --- Lobb's wild buckwheat

     See Nicholls, p. 117) and Eriogonum robustum (below). It should be noted that Lobb's wild buckwheat also occurs on the northern coastal ranges from southwestern Oregon (Josephine Co.) south into northwest California from Siskiyou and Trinity counties to Glenn, Humboldt, Lake, Mendocino and Tehama counties. While the plants of the Sierra Nevada are attractive, and those of high elevation in Mono and Inyo counties rather diminutive, plants from the coastal ranges are much more attractive and diverse in terms of local, minor variation. Habit and flowers.

Eriogonum loganum A. Nelson (Eucycla) --- Cache Valley wild buckwheat

     This species belongs to the Eriogonum brevicaule complex but differs from the other members in a number of minor, technical details. The plant is uncommon on sandy to gravelly slopes primarily in low-elevation sagebrush communities and juniper woodlands, or rarely on gravelly limestone slopes in high-elevation sagebrush communities and in subalpine conifer woodlands in Cache and Morgan counties, Utah. The low-elevation expression is now rare as most of the populations have been destroyed by recent construction on the Utah State University campus. Efforts to reintroduce the plant are ongoing so that cultivated material of this phase of the species is now available. The high-elevation expression is found along the backbone of the Bear River Range. It is this element that would be of interest to the rock gardener (see habitat and habitat. These plants form more dense mats (although less attractive than the tannish to olive-green mats found in and around Logan) with shorter flowering stems. Both expression produce plants with ochroleucous or yellow-flowers.

Eriogonum lonchophyllum Torr. & A. Gray (Eucycla) --- spear-leaf wild buckwheat

     No member of the genus is more frustrating taxonomically than Eriogonum lonchophyllum. The variation within the species is obvious, and given the long list of synonymy, various attempts to parse that variation have been made with limited success. The species is the southern counterpart to E. brevicaule. The spear-leaf wild buckwheat is an herbaceous perennial or spreading to erect subshrub with narrow to broad leaves, green and typically glabrous stems and branches, and white flowers. Eriogonum lonchophyllum is widespread and occasionally rather common in sagebrush-dominated communities in the Rocky Mountains of Colorado, northern New Mexico and eastern Utah. At the moment, only two varieties seem worthy of recognition, but even that may change. Typical var. lonchophyllum the plants are herbs to subshrubs with basal or more often narrow, cauline leaves (see habit). This expression is found in scattered location in the Rocky Mountains of Colorado and northern New Mexico (1600-2810 m elevation), and in eastern Utah (1400-2250 m). Within var. lonchophyllum as here defined, one finds the shrubby var. saurinum from the Dinosaur National Park in Daggett and Uintah counties, Utah, with disjunct populations near the abandon town site of Rainbow in southern Uintah Co., and in northwestern Rio Blanco Co., Colorado, as well as a high elevation expression from the Book Cliffs and Tavaputs Plateau regions of northeastern Emery, southern Uintah and northern Grand counties, Utah, and in Rio Blanco Co., Colorado, the var. intermontanum. To the south is E. humivagans, a plant of gravelly flats and slopes in mixed grassland, saltbush and sagebush communities, and in pinyon-juniper woodlands; it is known only from a few populations east of Monticello in eastern San Juan Co., Utah, and just over the state line in Montezuma Co., Colorado. All of these expressions are found on the western edge of the range of var. lonchophyllum in the strict sense. To the south, in scattered portions of northern New Mexico is the var. nudicaule. This is a depauperate plant with essentially linear, revolute leaves found mainly in Rio Arriba and Sandoval counties of New Mexico. Related to this phase of the species are E. coloradense and E. exilifolium (see above), both of which are worthy of consideration by the rock gardener. Some of the larger herbaceous perennials found in the Gunnison Basin of west central Colorado are worthy of consideration by the adventurous grower, but only as an item of curiosity. There is little to recommend var. fendlerianum either. This too is a subshrub but with much broader leaves. It occurs on silty clay flats and slopes in grassland and saltbush communities, and in juniper woodlands along the foothills of the Front Ranges in south central Colorado (El Paso, Fremont, Jefferson, Las Animas, Otero and Pueblo cos.) and adjacent north-central New Mexico (Colfax and Taos cos.). If properly maintained, this could be an attractive plant in the garden.

Eriogonum mancum Rydb. (Eucycla) --- imperfect wild buckwheat

     See Nicholls, p. 117. An understanding of Eriogonum mancum is only now falling into place, thanks to the discovery of a new species, E. soliceps (see below). As now understood, the imperfect wild buckwheat is a low mat with clusters of several small involucres subtended by a single series of basally fused (connate) bracts. The white flowers distinguishes this from the yellow-flowered E. verrucosum (see below), but yellow-flowered individuals will rarely be seen in populations of E. mancum (likewise, populations assigned to E. verrucosum with cream-colored flowers are also known). Eriogonum mancum is found on gravelly to clayey flats and slopes in mixed grassland, saltbush, sagebrush and mountain mahogany communities, and in juniper woodlands mainly from 1150-1950 m in southeastern Idaho (Butte, Clark, Custer and Lemhi cos.), southwestern Montana (Beaverhead, Broadwater, Carbon Deer Lodge, Gallatin, Granite, Jefferson, Lewis and Clark, Madison, Powell, Ravalli and Silver Bow cos.), and northwestern Wyoming (Big Horn Co.). Habitat (with Sedum lanceolatum), habit, and rose-flowered phase.

Eriogonum marifolium Torr. & A. Gray (Oligogonum) --- Lobb's wild buckwheat

     See Nicholls, p. 118. Like the other dioecious species of Eriogonum mentioned here (E. diclinum, E. incanum and E. polypodum), this one has markedly different male and female expressions so that it is not uncommon for collectors to consider each to be a different species. The plant forms a low, spreading mat that typically arises from a single, slender taproot even though the mat itself can be nearly a meter across. It may be recognized, as Nicholls says, by its olive-green leaves. The var. marifolium (see habit, male in the foreground, female in the background; female flowers; detail of female flowers and male flowers) is found in scattered populations often on volcanic peaks in Washington (Yakima Co.) and Oregon (Crook, Deschutes, Douglas, Hood River, Jackson, Jefferson, Klamath, Lane, Linn and Marion cos.), and north central California (Shasta, Siskiyou and Trinity cos.). The plant is much more common in the northern Sierra Nevada of California (Alpine, Amador, Butte, Calaveras, El Dorado, Lassen, Mono, Nevada, Placer, Plumas, Sierra and Tuolumne cos.) and in west central Nevada (Carson City, Douglas and Washoe cos.). An isolated population is found on the Pine Forest Range of Humboldt Co., Nevada. The var. cupulatum (Copeland's wild buckwheat, see habit of male and female plants, and male and female flowers), is a low elevation expression restricted to the pumice flats south of Mt. Shasta in Siskiyou Co., California. It has long, narrow leaves as opposed to the broader and more oval ones of the typical variety.

Eriogonum meledonum Reveal (Eucycla) --- Mabel's wild buckwheat

     Of the several species in the Eriogonum ochrocephalum/E. rosense complex, this is one of the more elegant members. Unfortunately, it is uncommon, being found only in two areas near Stanley, Custer Co., Idaho. As such, it is considered "in danger of becoming extinct" by the State of Idaho. South of Stanley, the plant tomentose scapes, but that to the northwest of Stanley has both tomentose (thinly so) and glandular scapes. Like its relatives, it is a low, cespitose matted perennial with densely grayish-white tomentose leaves and bright yellow flowers. It is the intensity of the leaf and flower colors that set this plant apart from others in the group, and therefore is what makes the species an attractive addition to the rock garden. See also E. verrucosum (below). Habitat, habit, detail of habit, and details of flowers.

Eriogonum microthecum Nutt. (Eucycla) --- slender wild buckwheat

     Of the twelve varieties now recognized within Eriogonum microthecum, four of interest to the rock gardener who desires small, compact plants suitable for an alpine setting. The Pahute Mesa wild buckwheat (var. lapidicola; see habitat, habit, and inflorescence) is a low, decumbent subshrub with a reddish-brown tomentum, small, elliptic leaves, and whitish-red to rose or orange flowers. This is found infrequently in the southern mountains of the Great Basin from Inyo Co., California eastward across central Nevada (Clark, Esmeralda, Lincoln, Nye and White Pine cos.) to western Utah (Juab and Washington cos.); it occurs from 2600-3100 m elevation. The Sonora Pass wild buckwheat (var. alpinum) is a true subalpine and alpine expression, being found in the central Sierra Nevada and the Sweetwater Range of California in Alpine, Mono and Tuolumne counties (see the habit). The tomentum of this plant is whitish. Johnson's wild buckwheat (var. johnstonii) is a subalpine form restricted to the upper reaches of the San Gabriel Mountains near the shared San Bernardino-Los Angeles county line in California where it is rare. Two low-elevation expressions occur in the central Great Basin. The scarlet wild buckwheat (var. phoeniceum -- Juab and Millard cos., Utah; see habit, detail of habitat, and flowers) and the Juniper Mountain wild buckwheat (var. arceuthinum -- Lincoln Co., Nevada and perhaps adjacent Utah) resemble var. lapidicola, with the former having tightly revolute leaves, and the latter having mostly glabrous and dark green leaves. Both are uncommon to rare. Depauperate populations of the Great Basin wild buckwheat (var. laxiflorum), yellow-flowered wild buckwheat (var. ambiguum; habit), and Simpson's wild buckwheat (var. simpsonii; see habit) are known. Of these, high elevation populations of var. ambiguum found mainly in White Mountains of Mono and Inyo counties of California, and in adjacent Esmeralda Co., Nevada, are worthy of consideration. Low elevation plants of var. simpsonii found on low clay hills in eastern Utah (and especially in Carbon and Emery cos.) are remarkably attractive, taking on the appearance of tiny trees. Similar plants are found on clay outcrops south of Salmon, Lemhi Co., Idaho. Of immediate concern is the about-to-be-described Bear Lake wild buckwheat (var. lacus-ursi). This plant is known from Bear Valley in the San Bernardino Mountains, San Bernardino Co., California, where it is restricted to a few hundred plants in a single area subject to development (see habitat, habit, and inflorescence and involucres). This would be an attractive plant to the garden but of a lesser value compared to other expressions of the species. An as yet undescribed shrubby expression, the var. schoolcraftii (Schoolcraft's wild buckwheat - see habit, inflorescences, and flowers), is a larger plant in all aspects than var. ambiguum. The new variety is restricted to arid mountains in southeastern Lassen Co., California, and adjacent Washoe Co., Nevada.

Eriogonum molle S. Watson (Eucycla) --- Cedros Island wild buckwheat

     This large, decorative shrub has been in cultivation since its formal naming in 1888. It belongs to a group of species characterized by E. giganteum (see above), but has its involucres and flowers reduced to a tight, capitate cluster atop long flowering stems. If past experience is any indication, Cedros Island wild buckwheat requires warm winters and a coastal, Mediterranean environment to do well in cultivation.

Eriogonum mortonianum Reveal (Eucycla) --- Fredonia wild buckwheat

     Being a diffusely branched shrub in the wild, it is unlikely this can be tamed to be come a reasonable picturesque example for the garden. Still, given its bright green and glabrous leaves, stems and branches highlighted by pale yellow to yellow or even white flowers, it might be worth of attempt. It is similar to northern counterpart, Eriogonum smithii (see below), and while both occur on red-colored soils -- a further enhancement of its greens and yellows especially -- the Fredonia wild buckwheat is restricted to gysophilous clay flats and outcrops, making its soil requirements especially challenging to the gardener. The species is known only from a limit area just west of Fredonia, Coconino Co., Arizona. habitat, habit, and detail on inflorescence branch.

Eriogonum natum Reveal (Eucycla) --- Mark's wild buckwheat

     Eriogonum natum is a rare plant known only from alkaline clay flats in saltbush communities in Millard Co., Utah, where it occurs near Sevier Lake. Mark's wild buckwheat is probably a recently evolved species as its entire habitat was buried under pluvial Lake Bonneville until some 10,000 years ago. Now isolated and morphological distinct, its point of origin was probably E. brevicaule var. cottamii, a plant of limestone outcrops in the hills to the north and east. Being related to E. brevicaule, it is a spreading, herbaceous perennial up to 3.5 dm high and 4 dm across. The leaves are elliptic in shape and densely tomentose abaxially, but less so and greenish tomentose adaxially. The flowering stems and cymose-umbellate inflorescence branches are a white to grayish tomentose; the flowers are a bright yellow. The plant flowers from mid summer into the fall of the year. Habit and detail of flowers.

Eriogonum nervulosum (S. Stokes) Reveal (Oligogonum) --- Snow Mountain wild buckwheat

     See Nicholl (p. 118 and again on p. 124). This is a low matted herbaceous perennial with compact basal rosettes of leaves and flowers that are ochroleucous at anthesis but become pinkish rose to deep red in fruit. Aside from an isolated site in Sonoma Co., California, the species is found mainly along the ridge system that separate Colusa and Lake counties from Snow Mountain in the north to southwest of Clear Lake in the south. The plant also is found in the Confusion Canyon area south and west of the Lake. See E. ursinum (below). Habit and detail of flowers.

Eriogonum niveum Douglas ex Benth. (Eucycla) --- snow wild buckwheat

     See Nicholl (p. 118). It not clear what Graham Nicholl had in mind when he described Eriogonum niveum var. dichotomum as taxonomically this is nothing more than typical E. niveum, a species restricted to sandy to gravelly flats, slopes, bluffs and rocky often volcanic outcrops in mixed grassland and sagebrush communities, and sometimes in montane conifer woodlands at elevations that range from 30 to 1100 or rarely 1300 m elevation from southern British Columbia south through eastern Washington and west central Idaho into northeastern Oregon. It is likely he confused this species with E. strictum var. greenei (of California) and also the var. proliferum.

Eriogonum nudum Douglas ex Benth. (Eucycla) --- naked wild buckwheat

     See Nicholl (p. 118). In addition to the three expressions (out of thirteen) mentioned by Nicholls (var. nudum - habit; var. oblongifolium, Harford's wild buckwheat; and var. scapigerum, Sierran crest wild buckwheat), two should also added. First is var. westonii (Weston's wild buckwheat). This is a large plant with glabrous, often bright green stems and branches in which the stems are often slightly inflated. The flowers are hairy and yet still an intense yellow. This is a species of arid habitat, being found in the drier portions of the southern San Joaquin Valley eastward onto the desert ranges of the northern Mojave Desert into Inyo Co. The second is var. paralinum (Port Orford wild buckwheat). This is the phase found on the coastal cliffs of Del Norte Co., California, and Curry Co., Oregon. In many respects it has the habit of E. latifolium (see above), but is smaller, more compact, and has glabrous stems and branches. For the record, the var. scapigerum is found in the Sierra Nevada up 3750 m, well above the 2955 mark given by Graham Nicholl.

Eriogonum nummulare M. E. Jones (Eucycla) --- money wild buckwheat

     This is not a pretty plant. It is a sprawling shrub with gangly branches, most grayish or at least a dirt tomentum, leaves that quickly dry and fall away, and ordinary white wild buckwheat flowers. It is also widespread throughout most of the Intermountain West from eastern California to central Utah and northwestern Arizona. Having disparaged the plant, one must hastily add that there are some scattered populations that might, just might, appeal to some gardeners. First, the shrubs found on moving sand (as at Sand Mountain in Nevada) may be useful in certain settings. The low, sprawling forms found on the western edge of old Lake Bonneville in Juab and Tooele counties of Utah, if carefully tended, could be attractive. Most likely the densely tomentose phase near Dugway, Tooele Co., Utah, is the most deserving of attention. With care and luck, this could be worthy of a place in the garden.

Eriogonum ochrocephalum S. Watson (Eucycla) --- white-woolly wild buckwheat

     See Nicholls, p. 118. In addition to the var. ochrocephalum (habit) mentioned briefly by him, there is also var. calcareum (Harper wild buckwheat; see habit and detail of flowers) of southwestern Idaho and southeastern Oregon, and the var. alexanderae (Alexander's wild buckwheat) which occurs mainly to the east of var. ochrocephalum in western Nevada. All are matted herbaceous perennials but with rather tall (up to 3.5 dm) scapes and capitate clusters of yellow flowers. For the most part, there are prettier species in this complex to consider for the rock and alpine garden. See E. anemophilum, E. argophyllum, E. breedlovei, E. capistratum, E. chrysops, E. crosbyae, E. cusickii, E. desertorum, E. diatomaceum, E. gracilipes, E. holmgrenii, E. kingii, E. mancum, E. meledonum, E. prociduum, E. rosense, E. scopulorum, E. soliceps, E. tiehmii, and E. verrucosum.

Eriogonum orcuttianum S. Watson (Eucycla) --- Orcutt's wild buckwheat

     It is difficult to evaluate this large, greenish shrub of central Baja California, Mexico. In the field it tends to be rather open with an off-color of green for its vegetation and a soft yellow fused with red for its flowers. It tends to grow in rocky places. With effort it might be made into a suitable shrub for the garden, but getting it established to a displayable size may prove difficult.

Eriogonum ovalifolium Nutt. (Eucycla) --- cushion wild buckwheat

     See Nicholls, p. 119. This is probably the most widely cultivated of the rock garden species of Eriogonum. The geographic distribution patterns Nicholls mentioned for each of the varieties is somewhat greater that he suggested. For example, the var. depressum (dwarf cushion wild buckwheat) is uncommon in Oregon (mostly Steens and Wallowa mountains) but much more common in Idaho, western Montana and northwestern Wyoming. This forms low mats of grayish leaves (habit and flowers). The var. nivale (Sierran cushion wild buckwheat; habit and flowers) is found mainly in the Cascade-Sierra cordillera from southern British Columbia to the southern tip of the Sierra Nevada. This expression forms low mats of whitish leaves. The recently described var. monarchense (Monarch wild buckwheat) is known only from a few individuals on limestone outcrops in the Kings Canyon area of Fresno Co., California. While its rareness might be attractive to rock gardeners, there are more attractive expression worthy of attention. The same is true of the federally endangered var. vineum (Cushionbury wild buckwheat) of the eastern San Bernardino Mountains of southern California, although its potential in the garden is greater than that of var. monarchense. The var. eximium (Slide Mountain cushion wild buckwheat) is found in California, on Job's Peak in Alpine Co., but most of the population is in the Carson Range of Carson City, Douglas and Washoe Co., Nevada. Allied to this is the federal endangered low-elevation var. williamsiae (Steamboat Springs wild buckwheat) of the Steamboat Springs area of southern Washoe Co. The high elevation var. caelestinum (heavenly wild buckwheat) of the Toiyabe and Toquima mountains of central Nevada (and the Bloody Canyon area near Tioga Pass in the Sierra Nevada) is worthy of attention given is low, matted habit and bright yellow flowers on short scapes. The same may be said of some local populations of var. purpureum, the purple cushion wild buckwheat. Forms of this variety occur on rocky, wind-swept ridges at low elevations in western Wyoming (especially in Park Co.) that mirror var. depressum is habit but with a whiter hue to their leaves. It is not know if such plants will retain their depauperate habit in cultivation. The image in the lower left on page 119 of Nicholls book is that of a female plant of E. caespitosum. There are several additional expressions of the species that are occasionally seen in the garden. The large yellow-flowered var. ovalifolium (see habit and flowers) and its white- or cream-colored counterpart, var. purpureum (see habit and flowers) are the most common. Much more restricted and actually more curious is the var. pansum of Blaine, Boise, Custer, Elmore, Lemhi and Valley counties in Idaho, and in Flathead, Lewis and Clark, Lincoln, Missoula, Powell and Silver Bow counties in Montana. This expression differs from all other expressions of the species in having long, narrow involucres on short (and often obscured) peduncles (see habit, inflorescence and flowers).

Eriogonum panguicense (M. E. Jones) Reveal (Eucycla) --- Panguitch wild buckwheat

     See Nicholls, p. 120. In addition to the var. alpestre (Cedar Breaks wild buckwheat; see habit and detail of flowers) mentioned by Nicholls, some populations of var. panguicense might be attractive in the garden, although the long scapes (up to 3 dm) will prevent them from becoming members of a rock garden display.

Eriogonum parvifolium Sm. (Eucycla) --- seacliff wild buckwheat

     See Nicholls, p. 120. Of the several coast expressions of wild buckwheats along the Pacific Coast of California, this is one of the more variable with several minor populations worthy of selection for the garden, and a few might even be suitable for the rock garden if severely pruned and shaped. The coastal forms found on the wind-swept bluffs overlooking the Pacific are the most attractive, being low, compact, and frequently wonderfully twisted and gnarled. As these are environmental induced features, as may be seen by examining plants just back from the more exposed sites, retaining them in cultivation will be challenging. Both white- (common) and yellow-flowered (Point Lobos in Monterey Co.) populations are known. Large, inland plants found in Santa Paula Canyon in Ventura Co. are highly attractive, although they too tend to sprawl.

Eriogonum pauciflorum Pursh (Eucycla) --- few-flower wild buckwheat

     See Nicholls, p. 120. The expression described by Graham Nicholls is the densely tomentose to lanate expression of the species with broad leaves often distinguished as var. gnaphaloides. This kind of plant is found in southeastern Wyoming, western Nebraska and in northeastern Colorado. This phase slowly gives may to the north (both to the west and east) to an expression with a looser kind of grayish tomentum on narrower leaves. Recent collections from Wyoming have so closed the morphological gap over such an extended geographic area that a taxonomic distinction between the two extremes can not be justified. Eriogonum pauciflorum occurs mainly the Great Plains from southern Saskatchewan and Manitoba south through the Dakotas and eastern Montana to northeastern Colorado and western Nebraska. As for the var. nebraskense, this is probably a hybrid involving E. pauciflorum and E. effusum given the profusely branched inflorescence of the plants. Collections of E. ´ nebraskense are known from Weld Co., Colorado, Kimball Co., Nebraska and Converse and Platte counties in Nebraska. Habitat, habit, detail of habit, and involucres and flowers

Eriogonum pelinophilum Reveal (Eucycla) --- clay-loving wild buckwheat

     Eriogonum pelinophilum, a federally-listed endangered species with designated critical habitat, is known only from Mancos Shale hills in Delta and Montrose counties, Colorado. It is similar to E. clavellatum (see above) although the two are well-separated geographically. Eriogonum pelinophilum is a smaller plant than E. clavellatum in habit. The flowers of E. clavellatum lack the pronounced rounded greenish-red to brownish-red united base of the perianth seen in E. pelinophilum, and the perianth lobes are distinctly dimorphic in E. clavellatum whereas they are essentially all of the same size in E. pelinophilum. Much of the former habitat occupied by E. pelinophilum has been destroyed since the species was listed in 1984. The species has proved difficult to grow. See a detailed presentation.

Eriogonum pendulum S. Watson (Eucycla) --- Waldo wild buckwheat

     This is a strange plant. It is an erect to slightly spreading shrub up to 5 dm tall and 8 dm across with tomentose leaves sheathing up the stems. The inflorescence consists of only a few, slender branches, with long peduncles (up 1 dm long) bearing solitary involucres filled with several large (to 7 mm), white, densely villous flowers. Here, even the achenes are covered with long, villous hairs. The species is rare to locally uncommon in the O'Brien-Waldo area of Josephine Co., Oregon, and in the Siskiyou Mountains (where more common) of Del Norte Co., California, as far south as Gasquet. It could be an attractive plant in the garden, but its placement would be critical for it appears to require space even in the wild. See also E. spectabile. Habit, inflorescence, and detail of flowers.

Eriogonum plumatella Durand & Hilg. (Eucycla) --- yucca wild buckwheat

     It is such desert species as the yucca wild buckwheat that causes one to question introducing any shrubby wild buckwheat into the garden. The species is an open, more or less erect shrub with wooly or glabrous stems and branches. Its few leaves tend to fall away. While the inflorescences do form rather curious, flat-topped and divaricately arranged arrangements of numerous branches, the white to pale yellow flowers are few and small. Add to these features the fact that the plant flowers sparingly only contributes to its sparse, twiggy look of seemingly dead twigs. In short, it is a rather ugly plant. Still, for those wishing a challenge, the species is infrequently encountered on the Mojave Desert of southeastern California, southern Nevada, and northwestern Arizona. Habit, inflorescences, detail of inflorescence, and flowers.

Eriogonum pondii Greene (Eucycla) --- Pond's wild buckwheat

     This low, spreading shrub of Cedros Island and the western Vizcaino Desert of Baja California is certainly worthy of cultivation. The large leaves, creamy-white flowers, and off-green vegetation all combine to produce an elegant shrub when fully covered with flowers as can be in case in protected areas. Plants away from the immediate coast tend to be larger, more floriferous, and better shaped. This could be an ideal border shrub or focus plant in a small planting. Habitat, habit and inflorescences.

Eriogonum prattenianum Durand (Oligogonum) --- Nevada City wild buckwheat

     Both expressions of this species, var. prattenianum and its southern counterpart, the Kettle Dome wild buckwheat (var. avium) would do well in the garden. These form large mats to erect shrubs with variously tomentose leaves. The erect flowering stems are terminated by capitate inflorescences of golden yellow flowers. Plants from Nevada and Placer counties in the Sierra Nevada of California tend to be more shrub-like than those from Madera and Tuolumne counties where a matted form is more common. It is the latter that would be attractive to the rock gardener. The var. prattenianum is found in widely scattered populations mainly on volcanic or granitic flats and slopes in manzanita and buckbrush communities from 800 to 2200 m elevation. The var. avium is restricted to a few, scattered populations on the western slope of the southern Sierra Nevada in Madera and Fresno counties, California; it occurs from 2500 to 2900 m where it enters montane conifer woodlands. Habit.

Eriogonum preclarum Reveal (Ganysma) --- splendid wild buckwheat

     There are only a few perennial species in the subgenus Ganysma, and all except Eriogonum inflatum occur in Baja California. Of these, the splendid wild buckwheat is the only one worthy of introduction into the garden. It is a low, spreading herbaceous perennial with long, dark green, thickish stems and branches. The large, dark green leaves tend to be confined to the base of the short, erect, main stem, while all along the numerous spreading branches are upright clusters of elegant yellow to rose flowers. Found in washes and along canyon walls near the ocean in the western portion of the Vizcaino Desert, finding the plant is a challenge, but the effort is rewarding and so too would its introduction into cultivation. Habit and flowers.

Eriogonum prociduum Reveal (Eucycla) --- prostrate wild buckwheat

     In many respects, the prostrate wild buckwheat competes with Mabel's wild buckwheat (Eriogonum meledonum, see above) for the prettiest of the E. ochrocephalum/E. rosense complex. Here, one has two expressions from which to choose. The var. prociduum has both leaf surfaces densely tomentose with its small flowers arranged in capitate clusters atop a scape less than 5 cm long. This plant is found on volcanic slopes in mixed grassland and sagebrush communities, and in pinyon-juniper woodlands from 1400 to 2400 m elevation in northern Lassen and Modoc counties in California, northern Washoe Co., Nevada, and southern Lake Co., Oregon. The yet-to-be-proposed var. mystrium (Pueblo Mountains wild buckwheat) has leaves that are merely floccose and thus greenish but with larger flowers on a longer scape (up to 9 cm). This expression is more widely distributed but rarer, being found on sandy to gravelly slopes in sagebrush communities from 1450 to 2400 m elevation in the Owyhee Mountains (South Mountain) of Owyhee Co., Idaho, the Santa Rosa Range (Auto Hill) of Humboldt Co., Nevada, and in a few spots in the Pueblo and Steens mountains of Harney Co., Oregon. Habitat, habit,and inflorescences and flowers.

Eriogonum pulchrum Eastw. (Eucycla) --- Meteor Crater wild buckwheat

     The Meteor Crater wild buckwheat belongs to the Eriogonum microthecum complex and is allied, as the ugly sister, with E. ericifolium. This is a low, spreading, somewhat matted subshrub with floccose and grayish-green, spreading stems and branches. The narrow leaves are slightly revolute or at least thickened, but lack the magic of those seen in E. ericifolium or in E. microthecum var. arceuthinum. The larger, more open inflorescence and the ordinary white Eriogonum flowers does little to promote this wild buckwheat as deserving a place in the garden. It is found on gravelly to rocky soil and outcrops in blackbrush and sagebrush communities, and in juniper or pinyon-juniper woodland in a series of scattered populations from northeastern Mohave Co., Arizona, eastward into the Apache, Coconino and Navajo counties. It is also found in northern Yavapai Co. Surprisingly, the species is occasionally seen in cultivation.

Eriogonum pyrolifolium Hook. (Oligogonum) --- Shasta wild buckwheat

     The Shasta wild buckwheat is occasionally seen in cultivation. It is a small, compact, matted plant most often found on volcanic-derived soils. The ovate to round leaves are in loose basal rosettes; they are bright green at least on the adaxial surface. The prostrate to weakly erect flowering stems vary from 3 to 18 cm in length, being terminated by capitate to umbellate inflorescences with white to rose flowers. Two varieties are traditionally recognized, although the taxonomic differentiation is dubious. The more common var. coryphaeum (hairy Shasta wild buckwheat - see habitat, Habit and flowers.) is found in the mountain of southern British Columbia south to northwestern California, and eastward across Idaho to western Montana. This phase has a lanate to tomentose abaxial leaf surface. The glabrous-leafed var. pyrolifolium often is restricted to volcanic peaks. In the Cascade Range, the var. pyrolifolium (see Habit and flowers)occurs only in Kittitas Co., Washington, and on Little Mt. Hoffman, Mt. Lassen and Mt. Shasta in Siskiyou and Shasta counties of California. Only in central Idaho (and to a lesser degree on the Bitterroot Mountains of Montana) is the plant relatively common and then nearly always with var. coryphaeum.

Eriogonum ripleyi J. T. Howell (Eucycla) --- Ripley's wild buckwheat

     This is a low, heavily branched subshrub known only from two areas in Arizona, one near Frazier's Well in Coconino Co. and a second near Cottonwood in Yavapai Co.; the species is considered a "sensitive" species in Arizona. It is related to Eriogonum pulchrum (see above), but is more attractive and worthy of consideration in the garden.

Eriogonum robustum Greene (Oligogonum) --- altered andesite wild buckwheat

     See Nicholls, p. 117, under Eriogonum lobbii). This is a larger, more robust expression than E. lobbii, and has a biumbellate (rather than simple umbellate) inflorescence. The large flowers (up to 9 mm long) vary from a creamy-yellow to a pale yellow. The species, already seen infrequently in cultivation, is restricted primarily to altered andesite soils in west-central Nevada essentially at the confluence of Carson City, Lyon, Storey and Washoe counties. Habit.

Eriogonum rosense A. Nelson & P. B. Kenn. (Eucycla) --- Mt. Rose wild buckwheat

     See Nicholls, p.120. In addition to the var. rosense mentioned by Nicholls (see habit and detail of flowers), there is also the var. beatleyae (Beatley's wild buckwheat). The first is the common yellow-flowered, matted, high-elevation (2300-4000 m) species of the Sierra Nevada (Sierra Co. south to Fresno and Inyo cos.) and higher mountain ranges just to the east (southern Washoe Co. to Esmeralda Co.) in Nevada. The latter is less common, being found mainly on volcanic tuffaceous outcrops at low elevations (1700-2500 m) in Eureka, Lander and Nye counties, Nevada. Only on the Toiyabe Range of central Nevada is the variety found at elevations approaching that of var. rosense. The var. rosense is occasionally found in cultivation and seemingly does well if, as mentioned by Graham Nicholls, it is properly trimmed and maintained. His recommendation applies to all of the members of the E. ochrocephalum complex (see above), to which can be added here the admonition to avoid over-watering. These are arid species, often of specialized soils, and are indeed "tender." Habit and detail of the flowers of var. beatleyae

Eriogonum saxatile S. Watson (Eucycla) --- hoary wild buckwheat

     See Nicholls, p. 120. The species also is found in the mountains of west central Nevada. See also E. crocatum.

Eriogonum scopulorum Reveal (Eucycla) --- cliff wild buckwheat

     Eriogonum scopulorum is known presently only from a few scattered locations in the Wallowa Mountains of Wallowa Co., Oregon, where it is rare on rocky granitic outcrops in sagebrush communities and in montane conifer woodlands; 2400-2850 m. Like other members of the E. ochrocephalum/E. rosense complex, this is a low, matted herbaceous perennial but with glandular hairy scapes and pale yellow, glabrous flowers. The small leaves (up to 1 cm long and 4 mm wide) are densely white tomentose and glandular on both surfaces. It is worthy of introduction as a rock garden plant.

Eriogonum shockleyi S. Watson (Eucycla) --- Shockley's wild buckwheat

     See Nicholls, p. 120. On the Colorado Plateau Eriogonum shockleyi has oblanceolate to spatulate leaf-blades mostly 0.3-1.2 cm long and 0.3-0.6 cm wide, scapes 1-3 cm long, involucres with long (2-3.5 mm) often spreading teeth, and flowers 3-4 mm long. This has been distinguished as var. longilobum. The typical Great Basin expression (see habit, detail of habit, and flowers)has elliptic leaves 0.3-0.6 cm long and 0.3-0.5 cm wide, scapes 0.5-2 cm long, involucres with short (0.5-2 mm) erect teeth, and flowers 2.5-4 mm long. Low, compact, hummock-like plants in southwestern Idaho (see habit) with elliptic leaf-blades 0.1-0.3(-0.35) cm long and 0.1-0.15 cm wide typically lack flowering stems, and have involucres 2.5-3 mm long with teeth 0.8-1 mm long; these have been termed var. packardae. Such morphological differences have been shown not to be genetically significant, however, and thus the species is no longer subdivided into varieties. Plants on moving sand dunes at the southeast end of Baking Power Flat in Lincoln Co., Nevada, can be up to 2 m across. Habit-wise this is a distinctive expression but like the others it does not seem worthy of taxonomic recognition. Habit and detail of flowers.

Eriogonum siskiyouense Small (Oligogonum) --- Siskiyou wild buckwheat

     See Nicholls, p. 121. Eriogonum siskiyouense is restricted to the ridge system that extends from the Scott Mountain area to the Mt. Eddy region of Siskiyou and Trinity counties, California. The vast majority of individuals in a population have but a single involucre atop each flowering stem, but at lower elevations and in somewhat more protected sites the inflorescence may be umbellate. Habit, detail of habit, matted habit, erect habit, branched inflorescences, capitate inflorescence, and leaves.

Eriogonum smithii Reveal (Eucycla) --- Flat Top wild buckwheat

     This is a large, erect to spreading, often diffusely branched, bright green and glabrous shrub up to 10 dm tall and 20 dm across; it has yellow flowers. Like the related Eriogonum mortonianum (see above), this should do well in cultivation with vigorous attention if the soil requirements can be met. Unlike that species, which is found on gypsophilous outcrops, E. smithii is a plant of moving sand that is rich in selenium. It is restricted to the San Rafael Desert of Emery and Wayne counties, Utah. Habit in moving sand, and habit in more exposed settings.

Eriogonum soliceps Reveal & Björk (Eucycla) --- Railroad Canyon wild buckwheat

     For the rock gardener, this new species (it will be formally proposed in 2004) likely will be an exciting addition. The species is outwardly similar to Eriogonum mancum, but has an inflorescence that is reduced to a single involucre atop a slender, scape-like peduncle. The usual three-parted (ternate) bract that normally subtends the involucre or group of involucres is lacking. The leaves are smaller, and the mat even more compact, than E. mancum. The new species is known currently from white outcrops of tuffaceous sandstones in eastern Lemhi Co., Idaho, and in Beaverhead, Deer Lodge and Mineral counties, Montana. See this detailed presentation.

Eriogonum soredium Reveal (Eucycla) --- Frisco wild buckwheat

     See Nicholls, p. 121. This is a magnificent rock garden plant that requires great care to maintain in cultivation. The mound-like growth, numerous flowers, and bright color all combine to make this worthy of the effort. Eriogonum soredium is a rare and localized species known only from the San Francisco Mountains of Beaver County, Utah. The Frisco wild buckwheat is a "sensitive" species in Utah. Habitat, habit, flowers, and detail of the flowers.

Eriogonum spectabile B. L. Corbin, Reveal & R. Barron (Eucycla) --- Barron's wild buckwheat

     Eriogonum spectabile is known only from about 250 individuals confined to gravelly soil in manzanita scrub and conifer woodlands north of Chester in the Lassen National Forest of Plumas Co., California. The U.S. Forest Service considers the plant to be a "sensitive species." It is also a candidate for possible state and federal protection. It is related to E. pendulum, but forms a much smaller and more compact shrub.

Eriogonum sphaerocephalum Douglas ex Benth. (Oligogonum) --- rock wild buckwheat

     See Nicholls, p. 121. In addition to var. sphaerocephalum (habit and flowers) and var. halimioides (halimium wild buckwheat - see habit, inflorescences, flowers, and details of the flowers) mentioned by Nicholls, there is also var. fasciculifolium (Weiser wild buckwheat). This expression has the same cream-colored flowers as var. halimioides but has glabrous leaves. As such, the Weiser wild buckwheat is a more attractive plant and would be a more appropriate selection for the garden; it is restricted southwestern Idaho in two disjunct populations (Adams and Washington cos. in the west and Blaine and Gem cos. to the east). It is likely that what has been termed Eriogonum douglasii var. sublineare (or var. tenue) is actually a fourth variant within E. sphaerocephalum. This low, somewhat matted subshrub has linear, revolute leaves. This expression is infrequently seen in cultivation, and clearly requires vigorous pruning to produce an acceptable plant for the decorative garden.

Eriogonum strictum Benth. (Eucycla) --- strict wild buckwheat

     See Nicholls, p. 121. Some minor additions and comments are necessary beyond those presented by Graham Nicholls. The var. proliferum occurs from 150-2700 m elevation and has white to rose or even purple flowers (see habit and flowers). This expression and Eriogonum niveum are sometimes difficult to separate, especially in southeastern Washington. The yellow-flowered var. anserinum (see habit) occurs from eastern Washington, eastern Oregon and northeastern California eastward into southwestern Idaho and northwestern Nevada. It grows from 150-2550 m elevation mainly in cold desert regions. The var. greenei (Greene's wild buckwheat - see habitat, habit, and flowers) is restricted to serpentine slopes and ridges in montane conifer woodlands from 1500-2400 m in the northern Coast Ranges of California, (Humboldt, Mendocino, Siskiyou, Tehama and Trinity cos). It is distinguished by its densely lanate leaves (see image)

Eriogonum suffruticosum S. Watson (Eucycla) --- bushy wild buckwheat

     Eriogonum suffruticosum is a rare, local species, being known only from limestone outcrops at five scattered locations in Brewster and Presidio counties in Texas. The relationship of this species to others in the genus is obscure. It is a low, spreading, highly branched subshrub with narrow, revolute leaves that are silky tomentose adaxially. The compact, cymose inflorescence is composed of both sessile and pedunculate involucres, the latter being campanulate in shape and augmented with six, reflexed lobes about half the length of the involucral tube. The flowers are yellowish-white with large reddish to maroon spots in the center; they can be up to 6 mm long. The perianth lobes are distinctly different. Those of the outer whorl are fan-shaped and about as long as wide with the tips recurved so as to expose the upright, oblanceolate inner perianth lobes. This would be an ideal plant for the garden, especially if the habit of the plant can be shaped into something attractive.

Eriogonum ternatum Howell (Oligogonum) --- ternate wild buckwheat

     Eriogonum ternatum is infrequently encountered in the coastal ranges of southwestern Oregon (Curry and Josephine cos.) and adjacent northwestern California (Del Norte and western Siskiyou cos.). It occurs mainly on sandy to gravelly often serpentine slopes and outcrops in manzanita and sagebrush communities, and in oak and montane conifer woodlands up to an elevation of about 2150 m. This is the basic expression of a series of species that includes E. libertini and E. congdonii. As such, the ternate wild buckwheat is a low, spreading, matted herbaceous perennial with often a brownish tomentum that takes on a blackish hue. The flowers are a sulphur yellow on an umbellate inflorescence. Habit.

Eriogonum thompsonae S. Watson (Eucycla) --- Thompson's wild buckwheat

     This is a robust herbaceous perennial of sandy to clayey flats and slopes in saltbush, blackbrush and sagebrush communities, and in pinyon-juniper woodlands in Kane and Washington counties of Utah, and adjacent Mohave Co., Arizona. The stems and branches of the rather large and mostly open inflorescences are bright green and glabrous. The flowers may be yellow or white. None of the varieties is particularly common, but essentially all seem to be confined to the red rock outcrops found in the area. The var. thompsonae itself is likely the most attractive member for the garden, having broad (oblanceolate to oblong or elliptic) leaves and yellow flowers (habit). The var. albiflorum (Virgin wild buckwheat - see habitat and habit) is similar but has white flowers; for the most part it is found geographically just to the west of var. thompsonae. On the southern fringe of the range is var. atwoodii (Atwood's wild buckwheat; habit). This has more or less linear leaves that often have slightly revolute margins and white to pale yellowish-white flowers. The var. matthewsae (Matthew's wild buckwheat; habit) may be a hybrid involving the var. albiflorum and E. corymbosum; it is now known (due to habitat changes) from a single individual near Springville in Washington Co., Utah.

Eriogonum thymoides Benth. (Oligogonum) --- thyme-leaf wild buckwheat

     See Nicholls, p. 122. As mentioned by Graham Nicholls, Eriogonum thymoides is an exquisite species that is found concentrated in three regions of the Pacific Northwest. The first occurs along the eastern edge of the Cascade Range from near Wenatchee, Washington (Adams, Benton, Chelan, Douglas, Franklin, Grant, Kittitas, Klickitat, Lincoln, Okanogan and Yakima cos.), to near The Dalles in extreme north central Oregon (Union Co.). The second occurs from Baker and northern Malheur cos., Oregon, to Adams, Canyon and Washington counties, Idaho. A third series of populations are in the Mount Bennett Hills area of Gooding Co., Idaho, with additional populations just over the surrounding county lines (Blaine, Camas, Elmore and Lincoln). Male plants tend to have yellow flowers that quickly fade after pollen release. Female plants tend to have white to pale yellow flowers that persist and greatly elongate as the achene matures.

Eriogonum tiehmii Reveal (Eucycla) --- Tiehm's wild buckwheat

     The plant is a low, cespitose, matted perennial with densely white or grayish tomentose leaves, a floccose scape, and yellowish white or whitish to cream, glandular flowers. It is known only from the Silver Peak Range of Esmeralda Co., Nevada. Tiehm's wild buckwheat is considered a "sensitive" species in Nevada. The species belongs to the large, rock garden attractive Eriogonum ochrocephalum complex (see above), in this case being found on rocky clay slopes and washes in saltbush communities at elevations of 1800 to 1900 m.

Eriogonum tripodum Greene (Oligogonum) --- tripod wild buckwheat

     This is a low, spreading, green and slightly hairy subshrub that is up to 5 dm tall and 6 dm across. It has a umbellate inflorescence that can be rather large and always open; the flowers are yellow and only about 5 mm long. Eriogonum tripodum occurs in widely scattered locations on serpentine flats, slopes and outcrops of the inner coast ranges of California (Colusa, Lake and Tehama cos.) and along the western foothills of the Sierra Nevada (Amador, El Dorado, Mariposa, Placer and Tuolumne cos.). The subshrub would make an impressive addition to the garden, but is less desirable than E. congdonii, for example. Habit and inflorescences

Eriogonum tumulosum (Barneby) Reveal (Eucycla) --- Woodside wild buckwheat

     See Nicholl (p. 122). Eriogonum tumulosum is infrequently encountered in Duchesne, Emery, Sevier and Uintah counties, Utah, and to Moffat Co., Colorado. The species is often confused with Parthenium ligulatum (M. E. Jones) Barneby (Asteraceae) as both grow together and forming dense hummock-like mats. It occurs on gravelly to clayey flats and slopes in saltbush and sagebrush communities, and in pinyon and/or juniper woodlands between 1650 and 2300 m. See also E. aretoides and E. shockleyi.

Eriogonum umbellatum Torr. (Oligogonum) --- sulphur flower

     See Nicholls, p. 122. This is the most variable species of Eriogonum, with some 40 varieties scattered through most of the western United States and southernmost southwestern Canada. The brief remarks here augment those by Graham Nicholls, with a few minor corrections. First, however, the illustrations. The one on the lower right of page 122 is E. arcuatum var. xanthum (see above). The images on page 123 are var. porteri (left) and var. sandbergii (right), the latter a yet-to-be-name variant.

     Var. torreyanum --- Donner Pass sulphur flower. This is a relatively rare plant being confined to sandy to gravelly granitic slopes in buckbrush and manzanita communities, and in montane conifer woodlands in Nevada, Placer and Sierra counties in the Sierra Nevada of California. Many of its historical sites were destroyed by road construction and development especially to the west and north of Lake Tahoe so that the number of present-day populations is limited. In fact, most of the collections made of this plant were gathered prior to 1900. The whole plant is glabrous and a bright but dark green. The large (to 10 mm), yellow flowers are arranged in a simple umbel.

     Var. glaberrimum ---Warner Mountains sulphur flower; see Nicholls, p. 122, who misapplied the name to var. torreyanum (see above). Like the var. torreyanum, the whole of the plant is glabrous, but here of a light, less intense grayish-green. The flowers too differ, being cream or whitish in color, and while the mats are more compact and larger, the height of the plant is about half that of var. torreyanum. The var. glaberrimum is a rare and localized taxon known only from the Warner Mountains of Lake Co., Oregon, and Modoc Co., California. At present the plant is known with certainty only from five locations.

     Var. umbellatum --- common sulphur flower. Widespread and common in the mountains of eastern Idaho, southwestern Montana, south through western Wyoming into northeastern Utah and the Rocky Mountains of Colorado (where it is the common expression). There is a phase in Montezuma Co., Colorado, and San Juan Co., Utah, that differs in have rounded leaves and may prove to be another variant.

     Var. cladophorum --- Yellowstone sulphur flower. Restricted to mineralize edges of the geyser basins in three locations (Upper Geyser Basin, Old Faithful and Madison Junction) within Yellowstone National Park, Teton Co., Wyoming. Differs from var. umbellatum in having lanate to densely tomentose leaf surfaces.

     Var. stragulum --- spreading sulphur flower. A phase with thinly floccose leaf surfaces of the foothills and adjacent mountains on and to the north of the Snake River Plains in Idaho; it just enters western Wyoming. Habitat, habit, and inflorescence.

     Var. aureum --- golden sulphur flower. This is one of the more widespread of the varieties being found from eastern Oregon, Idaho and western Montana south to southern Colorado, Utah and central Nevada. The leaves are essentially or entirely glabrous. This expression is commonly seen in cultivation, especially in European gardens.

     Var. porteri --- Porter's sulphur flower; see Nicholls, p. 123. Although traditionally accepted, this is little more than an alpine expression of var. aureum and may not be worthy of taxonomic recognition. At their extremes the two are markedly distinct, and based on limited observations of cultivated plants, the two maintain their basic habit when grown under uniform conditions. In Nevada (Elko, Lander and Nye cos.) the var. porteri grows with a similarly reduced alpine expression of the cream-colored var. desereticum. The plant is widely scattered mainly, usually above 2750 m elevation, in the Uinta and Wasatch mountains of Utah (Beaver, Duchesne, Iron, Piute, Salt Lake, Sevier, Summit, Uintah, Utah and Wasatch cos.) as well as in the Colorado Rocky Mountains (Chaffee, Delta, Garfield, Gunnison, La Plata, Moffat and Pitkin cos.).

     Var. hypoleium --- Kittitas sulphur flower. The western, disjunct expression of var. aureum confined to montane and subalpine settings in Chelan and Kittitas counties, Washington. It differs from most (but not all) populations of var. aureum in having hairs on the edge of the leaf blades.

     Var. sandbergii --- Sandberg's sulphur flower. One of the several yet-to-be-named varieties of Eriogonum umbellatum from the foothills and low mountains of the north Cascade Ranges of north central Oregon (Hood River and Wasco cos.) and central Washington (Chelan, Kittitas, Okanogan and Yakima cos.). It appears to be most closely related to the more southern, and matted, var. modocense, being a low, loosely matted perennial with leaves that are lanate abaxially and generally glabrous or nearly so (and bright green) adaxially. This has long passed as var. umbellatum in the Pacific Northwest.

     Var. hausknechtii --- Hausknecht's sulphur flower; see Nicholls, p. 122. A low, typically prostrate, mat former with tannish-tomentose abaxially leaf surfaces and thinly tomentose to glabrous and typically olive-green adaxial surfaces. It is a high elevation variety found mainly on volcanic peaks in north central Oregon (Benton, Clackamas, Hood River, Linn and Wasco cos.) and in south central Washington (Kittitas, Klickitat, Skamania and Yakima cos.). The variety is common on Mt. Hood and Mt. Adams. The var. hausknechtii is typically found growing with E. marifolium so that mixed collections of the two often are found in herbaria, a distinctive olive-green color to the upper leaf surface being common to both. Hausknecht's sulphur flower is not always clearly distinct from var. modocense. It is occasionally seen in cultivation, especially in European gardens.

     Var. canifolium --- Sherman Pass sulphur flower. This plant is infrequently found in the southern Sierra Nevada of Inyo and Tulare counties, California, and in the Argus Mountains to the east. The densely lanate leaf surfaces and the low, matted habit are distinctive features especially when compared with the more commonly encountered var. nevadense of the Sierra Nevada. As the plants mature the amount of tomentum on the upper surface of the leaf-blades thins and can become floccose or even glabrous on individual leaves. The name has yet to be published.

     Var. modocense --- Modoc sulphur flower. It was a selection from this variety that resulted in the widely popular "Alturus red" so frequently seen in America gardens today. The variety is the common form of the species encountered mainly east of the Cascade Range from central Oregon (Crook, Deschutes, Douglas, Grant, Harney, Jackson, Jefferson, Josephine, Klamath, Lake and Malheur cos.) to northern California (Butte, Lassen, Modoc, Shasta and Siskiyou cos.). The variety is less frequently found in northernmost Nevada (Humboldt and Washoe) and southwestern Idaho (Camas, Goodding, Owyhee and Twin Falls). In the northern Sierra Nevada var. modocense merges with var. nevadense. In California and Nevada, plants now assigned to this name have generally gone under the name E. umbellatum var. polyanthum in the pre-1989 literature; it is so treated by Nicholls, p. 123. Habitat, habit, and leaves and flowers.

     Var. dumosum --- American Valley sulphur flower. Of the several varieties of Eriogonum umbellatum that forms shrubs, this is one of the more attractive, being up to 5 dm tall and 10 dm across. The flowers are bright yellow and on the larger size (up to 9 mm). It occurs on sandy to gravelly flats and slopes in mixed grassland communities, and in oak and conifer woodlands in widely scattered locations where it is local and typically infrequent in Amador, Placer, Plumas, Shasta and Siskiyou counties in California, and just inside Oregon (in Jackson Co.). It approaches var. nevadense in size but differs in having much more densely tomentose leaf-blades. Also, the var. dumosum can be confused with var. modocense, a much smaller plant nearly always to the east or north of var. dumosum. Unlike the related var. ahartii (see below) that is always on serpentine soils, the var. dumosum is only occasionally found on this substrate. Habitat, habit, inflorescences, and flowers.

     Var. goodmanii --- Goodman's sulphur flower. This is a low, spreading mat-former with densely lanate abaxial leaf surfaces and tomentose to rarely floccose adaxial surfaces. The flowering stems are rather long (to 4 dm) as are the yellow flowers (to 9 mm long). It is found on sandy to gravelly serpentine flats and slopes in mixed grassland communities, and in oak and montane conifer woodlands mostly below 1700 m. It is common only in the Waldo area of Josephine Co., Oregon, although it is also found in Benton, Deschutes and Douglas counties in Oregon, and in Del Norte, Humboldt and Siskiyou counties, California. It merges with var. modocense on the eastern edge of its range, particularly in Siskiyou Co. and in Deschutes Co., Oregon.

     Var. humistratum --- Scott Mountain sulphur flower; see Nicholls, p. 123. This expression is restricted to exposed serpentine areas in four areas in Siskiyou and Trinity counties of northern California: White Mountain, Mt. Eddy-Scott Mountain, the Marble Mountains, and Mt. Shasta. Habit and detail of habit.

     Var. nevadense ---Nevada sulphur flower. Graham Nicholl (p. 123) misunderstood var. nevadense, seemingly confusing this with var. covillei (see below). The var. nevadense is a low, mostly spreading subshrub with thinly tomentose to floccose leaf blades. This is the common phase of the species at lower to mid elevations (mostly 1500-3000 m) in the Sierra Nevada and in the desert ranges of the western Great Basin. The variety is found from southern Modoc and Lassen counties of California south to Inyo and Kern counties; in Nevada is extends across the Great Basin to Elko and White Pine counties. In the northern Sierra Nevada of California, and in the Granite Range of Washoe Co., Nevada, it merges with var. modocense. At higher elevations in the Sierra Nevada, it grades into var. covillei. The Nevada sulphur flower is occasionally found in cultivation. Habit.

     Var. vernum --- spring-flowering sulphur flower. The related Nevada sulphur flower flowers normally from June into September, so the pale- to bright yellow-flowered var. vernum, a shrub up to 9 dm tall and 13 dm across, is rather obvious when it is in full flower in May and early June. The variety is confined to mainly volcanic flats and slopes in saltbush and sagebrush communities in northern Nye Co., Nevada. Habitat and habit.

     Var. covillei --- Coville's sulphur flower. This is a high elevation derivative of var. nevadense. It occurs on gravelly rocky or talus slopes and ridges in high elevation sagebrush communities, and in alpine conifer woodlands from 3050 to 3550 m elevation in the Sierra Nevada of California in Inyo and Tulare counties, and on the White Mountains in Mono Co. Unlike its subshrubby counterpart, Coville's sulphur flower forms a low, prostrate mat. Habit and flowers.

     Var. mohavense --- Mohave sulphur flower. The var. mohavense is known only from the Black Rock and Wolf Hole mountains area on the Arizona Strip of Mohave Co., Arizona, and the Pine Valley Mountains of Washington Co., Utah. The rays or branchlets of the inflorescences are rather long (2-8 cm) and the leaves rather narrow. This is related to the compound umbellate var. subaridum (see below), but is a much smaller plant and flowers in the spring and early summer (rather than late summer and fall). This variety remains to be formally named. Habit of young plant and flowers.

     Var. minus ---Old Baldy sulphur flower; see Nicholls, p. 123.

     Var. nelsonii --- Nelson's sulphur flower. This is a difficult variety to recognize as a pressed and dried herbarium specimen without good label data. It forms low spreading mats or subshrubs up to 7 dm across with leaves that are densely white tomentose to lanate abaxially, greenish-white tomentose to floccose or rarely glabrate adaxially. It is known only from three locations: in Humboldt and Trinity counties, California. However, plants from the Scott Bar Mountains of Siskiyou Co., California, may well proved to be var. nelsonii. In spite of its simple umbel, the variety is most closely related to var. smallianum (see below).

Plants with pale yellow to cream or whitish flowers and a simple umbel. See var. vernum (above) and var. versicolor (below).

     Var. dichrocephalum ---bicolor sulphur flower. The var. dichrocephalum is widespread and common throughout most of the arid Intermountain West, extending into portions of central Idaho, western Montana, and western Wyoming beyond that floristic region. The plant has the habit of var. aureum but with the leaves of var. umbellatum. Plants in Montana and Wyoming are not always clearly differentiated from var. majus, the key being that the tomentum of var. dichrocephalum tends to be more whitish while that of var. majus is rustic. Furthermore, the upper surface of the leaves in the latter tends to be olive-green, a color not seen in var. dichrocephalum. Finally, the leaves of var. majus tend to be longer and narrower, and the entire plant forms a flat, dense mat, a condition not usually seen in the more loosely arranged mats of var. dichrocephalum. Habit.

     Var. desereticum --- Deseret sulphur flower. Like the var. aureum, this expression has essentially glabrous leaves but with pale yellow to cream-colored flowers. It is less widely distributed than var. aureum, being found in southern Idaho, southwestern Montana and western Wyoming, south into northeastern Nevada and northern Utah. Depauperate, high elevation populations may be seen in the Ruby Mountains of Elko Co., Nevada; it is this phase of the variety that would be an attractive addition to the rock garden, especial since the glabrous leaves turn a bright rust-red in the fall of the year. Habitat, habit, habit of small plant, detail of habit, flowers, detail of male flowers, and detail of female flowers.

     Var. majus --- subalpine sulphur flower; see Nicholls, p. 123, as var. subalpinum. The variety is distinct from and often grows with var. umbellatum in Colorado leading many local taxonomists to distinguish the two at the species rank, namely Eriogonum subalpinum. In Wyoming and Montana, however, var. majus occasionally becomes difficult to differentiate from var. dichrocephalum. It is widespread and common in the Rocky Mountains of southern Canada south to southern Colorado, and then westward into northern Utah, northeastern Nevada, and onto the Cascade Range of Washington where uncommon. The large, prostrate mats with their numerous compact clusters of leaves that are densely whitish-, greenish- or reddish lanate abaxially, and olive-green to bright green and glabrous adaxially, lend the plant to be an attractive ground cover. habitat, habit and flowers.

     Var. ellipticum --- starry sulphur flower. The inflorescence of this northern expression may be divided two to four times, creating a large mass of thinly floccose to glabrous green stems and branches dotted with clusters of yellow flowers, all arising from a small, compact mat. In the field, the flowering stems can be long and "leggy," and thus tending to collapse under their own weight. The plant is found on sandy to gravelly flats and slopes in mixed grassland and sagebrush communities, and in montane conifer woodlands from 700 to 2400 m in the mountains of the Pacific Northwest from southeastern Washington (Asotin, Columbia, Garfield and Walla Walla cos.), eastern Oregon (Baker, Grant, Harney, Malheur, Morrow, Umatilla, Union and Wallowa cos.), Idaho (Ada, Adams, Bannock, Bingham, Blaine, Boise, Custer, Elmore, Gem, Lemhi, Nez Perce, Owyhee, Washington and Valley cos.) and central western Montana (Ravalli Co.). This expression was long known as var. stellatum. Habitat, habit, and inflorescences.

     Var. devestivum --- emperor's sulphur flower. Similar in all ways to var. ellipticum except the leaves are essentially, if not in fact, glabrous. It is found infrequently in similar habitat in Asotin and Columbia counties, Washington; Baker, Grant and Union counties, Oregon; and, in Ada, Adams, Blaine, Lemhi, Valley and Washington counties in Idaho. The plants are bright and showy. Habit, detail of habit, male flowers, and female flowers.

     Var. furcosum --- Sierra Nevada sulphur flower. This is the Sierra Nevada expression that occurs in California from Sierra Co. south to Inyo and Kern counties, and in the Carson Range of southern Washoe Co., Nevada. Here the plants are low, rounded subshrubs up to 3 dm tall and 8 dm across, with smooth leaf margins. Habit.

     Var. argus --- one-eyed sulphur flower. The var. argus occurs in the Siskiyou/Trinity mountains of Josephine and Jackson counties, Oregon, and in Del Norte, Glenn, Humboldt, Plumas, Siskiyou and Trinity counties, California. It is the serpentine counterpart to var. furcosum of volcanic and granitic soils in the Sierra Nevada; the var. argus is a more elegant plant and much more attractive. The inflorescences are nearly always compound but open, and the flowering stem frequently has a single foliaceous bract about midlength. The wavy-margins of the leaf-blades marks this variety as distinct from the others. Habit, detail of habit, female flowers, and male and female flowers.

     Var. smallianum --- Small's sulphur flower. This variety occurs in the northern coastal ranges of California (Glenn, Lake, Mendocino, Sonoma, Tehama and Trinity cos.) and is the northern counterpart to var. bahiiforme. The plants form low, spreading mats of leaves that are lanate to tomentose only on the abaxial surface. They are found on sandy to gravelly, mostly serpentine flats and slopes in oak and montane conifer woodlands,

     Var. bahiiforme --- Santa Clara sulphur flower. Here, compared to var. smallianum, the mats of leaves are densely white to gray lanate on both surfaces. The plants likewise occur on sandy to gravelly, mostly serpentine flats and slopes in oak and montane conifer woodlands, but well to the south in the central coastal ranges of California (Colusa, Contra Costa, Monterey, Napa, San Benito, Santa Clara and Sonoma cos.), with a disjunct population in the San Gabriel Mountains of Los Angeles Co. It is likely that the depauperate var. minus (see above) is allied to this variety.

     Var. subaridum --- Ferris's sulphur flower. This expression is widespread across the southern portion of the species' range from southeastern California (Ventura Co.) eastward across southern Nevada , central and southern Utah and northern Arizona (Coconino, Mohave and Navajo cos.) to southwestern Colorado (La Plata and Montezuma cos.). For the most part the plant is a low, usually rounded subshrub, but in Utah, at higher elevations in the southern Wasatch Mountains, it can be matted, while on the edge of the Mojave Desert and at the southern extreme of the Colorado Plateau in northern Arizona and southwestern Utah, shrubby plants can be found. In southeastern Utah some populations mimic var. munzii (see below), while in southwestern Utah, others approach var. chlorothamnus (below).

     Var. chlorothamnus --- Sherwin Grade sulphur flower. This expression of Eriogonum umbellatum deserves a place in the garden. Bright green and essentially glabrous throughout, the large subshrub to shrubs of the eastern slope of the Sierra Nevada in Inyo, southern Mono and northeastern Tulare counties, California, is stunning in the wild. Although the bright yellow flowers are on the small side (only up to 6 mm long), their small size is made up by their sheer number. Habit and inflorescences.

     Var. munzii --- Munz's sulphur flower. The var. munzii occurs mainly in the transverse ranges of California basically along the edge of the Mojave Desert from southern Santa Barbara and northern Ventura counties eastward across southern Kern Co. to northwestern San Bernardino counties, then south into portions of northern Los Angeles Co. The taxon is then disjunct to the San Jacinto Mountains, Riverside Co. (where the leaves are tomentose on both surfaces), and the Laguna Mountains, San Diego Co. It is the southwestern element related to var. subaridum, and a clear distinction between the two variants is not always sharp. Generally, the leaves are densely white tomentose only on the adaxial surface. Habit and inflorescences

     Var. lautum --- Scott Valley sulphur flower. Of all the yet-to-be-described compound umbellate sulphur flowers, this large (up to 10 dm across), low, spreading mat with leaves densely white tomentose to lanate abaxially and greenish-white tomentose, rarely some floccose or even glabrous adaxially, with large compound umbels and bright yellow flowers is the most worthy of cultivation. The var. lautum is restricted to the Scott Valley area of Siskiyou Co., California. habit, detail of habit, inflorescens, and leaves.

     Var. polyanthum --- American River sulphur flower. The name, var. polyanthum, has been widely misapplied to plants here called E. umbellatum var. modocense and var. dumosum. The inflorescences are commonly compound umbellate, but plants with a reduced, yet bracteated inflorescences do occur. Those with a reduced inflorescence technically consists of a long (6-10 cm), central, bractless peduncle, and two lateral branchlets (3-4 cm) each bearing a peduncle (3-6 cm). The latter have a whorl of foliaceous bracts between the flowering stem and the involucres (technically at the base of the peduncle). Specimens with a reduced inflorescence are uncommonly. Even so, the more common, branched-inflorescence expression of the species is rare throughout its range on the western foothills of the Sierra Nevada in Butte, Plumas and Sierra counties where it occurs on serpentine flats and slopes in oak and montane conifer woodlands from 800 to 1425 m. The plant forms a round, rather open shrub up to 10 dm tall and across.

     Var. speciosum --- beautiful sulphur flower. This large, rounded to spreading shrub (up to 15 dm tall and 20 dm across) is a rare plant that is known presently only from a few scattered locations in Humboldt and Trinity counties, California. The name has been widely misapplied to var. dumosum, var. polyanthum, and especially var. ahartii. This large and showy shrub is certainly worthy of cultivation because of its large flowers (up to 12 mm long). It occurs mainly on serpentine flats and slopes mainly in oak and pine woodlands at 100 to 800 m. Habit and inflorescence.

     Var. ahartii --- Ahart's sulphur flowers. Of the several shrubby varieties of Eriogonum umbellatum, this is probably the most attractive. It forms large, densely branched shrubs up to 8 dm tall and 13 dm across, with large leaves that are densely rusty lanate to tomentose abaxially, and floccose to glabrous and olive-green adaxially. It too occurs on serpentine in oak and pine woodlands, only from 400 to 2000 m in the Paradise and Lumpkin Ridge areas of Butte Co., California. Habit.

     Var. cognatum --- Flagstaff sulphur flower. The leaves of this variety are decidedly more rounded than most seen in Eriogonum umbellatum, and the whole plant smaller and more compact than most, being at most only about 3 dm across. The leaves are white tomentose abaxially, but thinly floccose or more commonly glabrous adaxially. It is a plant of sandy flats and slopes in sagebrush communities, and in oak and montane conifer woodlands in south central Coconino Co., Arizona, and just over the political boundaries in Gila and Yavapai counties. The plant is most frequently seen in the greater Flagstaff area. Inflorescences and leaves.

     Var. versicolor --- Panamint sulphur flower; see Nicholls, p. 124. Although some populations at higher elevations might be considered "dwarf," most are composed of rather open, spreading mats. The leaves vary from white tomentose abaxially and floccose adaxially to (albeit rarely) tomentose on both surfaces. The flowers vary greatly from a cream to reddish-brown or even a rose, and often with a large, darker colored (red to maroon) spot on each of the outer (at least) perianth lobes. The var. versicolor occurs infrequently in scattered mountain ranges across southern Nevada (Clark, Eureka, Lincoln, Lyon, Nye and White Pine cos.) into California (eastern Inyo and Mono cos,) where it may be somewhat more common.

     Var. juniporinum --- juniper sulphur flower. In this widespread but infrequent variant the leaves are floccose to glabrous on both surfaces. It occurs in widely scattered and disjunct populations in isolated desert mountain ranges from southern Utah (Navajo Mountains, San Juan Co. and Beaverdam Mountains, Washington Co.) and north central Arizona (Kaibab Plateau, Coconino Co.) westward across southern Nevada (Spring Range of Clark Co., Mt. Irish and Mormon Range in Lincoln Co. and Schell Creek and Snake ranges in White Pine Co.) to California (southeastern Inyo and northeastern San Bernardino cos. - mainly Clark Mountain and the Kingston, New York and Providence ranges, and in the Mid Hills).

Eriogonum ursinum S. Watson (Oligogonum) --- Bear Valley wild buckwheat

     See Nicholls, p. 124. Eriogonum ursinum is rather common in the northern Sierra Nevada of California (Lassen, Nevada, Placer, Plumas, Shasta and Sierra cos.), with a series of disjunct populations on the Trinity-Tehama-Shasta county lines. A low elevation population (Hutchinson et al. 2693; JEPS) is known from near Pulga along the Feather River in Butte Co. Bear Valley wild buckwheat forms large, colorful mats on the forest floor with rather compact but compound divided umbels of pale yellow flowers. The plant does well in the garden. See E. erubescens (above). Habitat, habit, inflorescences, and flowers.

Eriogonum verrucosum Reveal (Eucycla) --- graceful wild buckwheat

     The distinguishing feature of this member of the Eriogonum ochrocephalum/E. rosense complex is the pustulose or bumpy texture of the flower base and midribs of the perianth lobes. This feature is occasionally seen, usually with difficulty, in E. mancum, and certainly in E. soliceps. Like E. mancum, the graceful wild buckwheat is a low, cespitose, matted perennial with numerous oblanceolate to spatulate leaves that are densely white tomentose on both surfaces or abaxially and greenish-white adaxially. In the strict sense, the species is known from Custer and western Lemhi counties, Idaho, mainly along the Salmon River drainage, and in the mountains to the south (western slope of the Lost River Range and in the Spar Canyon area to the west). The plant also is known from White Knob Mountains east of Mackay, and from the Blizzard Mountains of northern Butte Co. Most populations consist of yellow-flowered plants with thinly floccose scapes. However, west and south of Challis (Morgan Creek and Lime Creek areas) are mixed populations of cream- and yellow-flowered plants. The White Knob Mountains populations along Alder Creek are essentially all cream-flowered although some plants may be found with a hint of yellow. Some populations have only glabrous scapes where mixed populations are more common. Plants from the Spar Canyon area can vary from glabrous to densely tomentose. In the Salmon area of eastern Lemhi Co., Idaho, one finds large, cream-flowered plants with oblong to obovate leaves. A similar kind of plant, but with yellow flowers, was collected on red, silty clay mounds with saltbush on the Sheldon National Wildlife Refuge in northern Humboldt Co., Nevada. A full, taxonomic understanding of this species awaits more study. Habit, detail of habit and detail of involucres and flowers

Eriogonum villiflorum A. Gray (Eucycla) --- gray wild buckwheat

     See Nicholls, p. 124). The species is inconspicuous and easily overlooked in the field. It ranges from Beaver, Iron, Juab, Kane, Millard, Sanpete and Tooele counties, Utah, and from Eureka, Lincoln, Nye and White Pine counties, Nevada. The Kane Co., Utah, location where the species was first discovered is questionable as this is well out of the known range of the plant today. The sprawling nature of the flowering stems with the largest clusters of involucres and wooly flowers is distinctive. See also E. aretioides, E. shockleyi and E. tumulosum.

Eriogonum wrightii Torr. ex Benth. (Eucycla) --- bastard-sage

     See Nicholls, p. 124). The species consists of nine varieties, only three being of interest to the rock gardener. In addition to the var. subscaposum (short-stemmed bastard-sage) mentioned by Graham Nicholls, there is the alpine var. olanchense (Olanche Peak bastard-sage) of granitic talus slopes above 3500 m elevation on Olanche Peak in Tulare Co., California. The plant forms tight, compact mats up to 6 cm tall and 3 dm across. The flowers, like others of the species, vary from white to pink but here are in capitate (or nearly so) clusters rather than on more open, branches inflorescences. In the Sierra San Pedro Matír of Baja California Norte, Mexico, one finds the var. oresbium (montane bastard-sage). This is much more like var. subscaposum is habit. Among the other members of the species, one might find some forms of var. trachygonum (rough-node bastard-sage) worthy of cultivation, especially those that are densely lanate from the coastal ranges of central and northern California. Already in cultivation are both var. membranaceum (ring-stemmed bastard-sage) on southern California and northern Baja California, and its more southern counterpart, the var. taxifolium (Cedros Island bastard-sage) of coastal Baja California Norte and some of the off-shore islands. These are well-formed subshrubs with small, elliptic leaves. The more shrubby members of the species, notably var. nodosum (knot-stem bastard-sage) of southeastern California and var. pringlei (Pringle's bastard-sage) of Arizona, while up to 10 dm tall and 13 dm across, are just too scraggly to be attractive in most garden settings. Still, the tiny involucres and flowers of Pringle's bastard-sage are curious, and the dense lanate condition of the stems, branches and leaves of both varieties (and one yet to be described from east central Baja California) are pleasing. In an open, roomy arid garden, any of these three expressions might be worthy a try.

Eriogonum zapatoense Moran (Eucycla) --- Islote Zapoto wild buckwheat

     Aside from Eriogonum encelioides (see above) of the E. giganteum complex, this rare and highly restricted shrub is the most worthy of cultivation. What is attractive here are the numerous yellow flowers that should, if properly trimmed and groomed in the garden, complete cover the entire shrub. The species is known only from a small islet off the Isla Guadalupe, well in the Pacific Ocean off the coast of central Baja California, Mexico.

Eriogonum zionis J. T. Howell (Eucycla) --- Zion wild buckwheat

     There are four species in the Eriogonum racemosum complex, a group found from the desert ranges of eastern California to the Rocky Mountains of Colorado. Of these, E. racemosum, E. rupinum, E. panamintense, and E. zionis, only the latter has any attributes worthy of a place in the garden, although one can find E. racemosum in cultivation. While the generally glabrous stems and branches, large leaves and white to pale yellow or yellow flowers of this more or less erect herbaceous perennial means that the var. zionis might strike someone's fancy (see the flowers), its is the bright red flowers of the var. coccineum that truly is remarkable (see the flowers). The var. zionis is found in scattered populations in Kane, San Juan, Washington and Wayne counties, Utah, and in northern Coconino Co., Arizona, while the var. coccineum is a rare and local plant known only from two populations on the edge of Grand Canyon (1950-2300 m) in Coconino Co., and in the Hack Canyon area (1400-1500 m) of Mohave Co., Arizona.

Posted 28 Sep 2003; last revised 7 Oct 2003.
James L. Reveal.