Flower:

Clusters of 5 to 15 flowers at tips of lateral branches on 1-year-old stems. Flowers are white, 1/3 to ½ inch across with 5 oblong to narrowly spatula-shaped petals that are initially erect, becoming ascending to widely spreading. In the center is a cluster of many styles surrounded by a ring of numerous white stamens. Alternating with the petals are 5 sepals, broadly triangular tapered to a long, tail-like tip, longer than the petals, widely spreading to curved downward (recurved), pale green to gray-green, the outer surface covered in soft, non-glandular hairs. Flower stalks are hairless to short-hairy, with scattered broad-based, cat-claw-like prickles.

Leaves and stems:

Leaves are alternate and compound with typically 3 leaflets (trifoliate), rarely 5. Leaflets are egg-shaped to elliptic, mostly widest below the middle, the center leaflet long stalked, the lateral leaflets stalkless and occasionally shallowly lobed, typically 2 to 4 inches long, 1¼ to 3 inches wide, sometimes larger, with a long taper to a slender, pointed tip and rounded to heart-shaped at the base. Edges are coarsely double-toothed, upper surface is medium to dark green, mostly smooth, the lower surface silvery and densely hairy.

Leaf stalks are mostly smooth with a few straight to recurved prickles. At the base of the compound leaf stalk is a pair of thread-like appendages (stipules) about ¼ inch long. Stems up to 12 feet long, covered with a waxy bloom and scattered, very sharp prickles that are straight to slightly curved or angled downward. Stems are strongly arching and root at the tips. New canes (primocanes) are light green to blue-green, second year canes (floricanes) produce the flowering branches and are often reddish, the canes dying before the third year but new canes emerging from the rooted tips.

Fruit:

Fruit is round cluster, about ½ inch in diameter of fleshy druplets, turning purplish-black when ripe, do not easily pull free from the receptacle, and are quite tasty.

Notes:

Black Raspberry is common throughout much of southern Minnesota and frequently found along roadsides and hiking trails. Its range northward is mostly limited by winter hardiness. Its seeds are readily and widely disseminated by both birds and mammals and establish easily, after which tip layering (rooting at the tips) often creates dense, nearly impenetrable colonies. It is easily recognized and "going black cap picking" is a favorite pastime. While it can be tempting to sneak an early taste of the near ripened berries, they will be quite tart until they've turned a dark purple black.

Rubus is a large and difficult genus; both flowering (floricane) and non-flowering (primocane) stems from the same plant may be necessary for a positive ID. Characteristics to look for are the size and shape of the flower, whether there are glandular and/or non-glandular hairs (on sepals, leaves, stalks and/or stems), whether there are any broad-based prickles or slender bristles, number of leaflets and whether they are palmately or pinnately compound, whether the fruit easily separates from the receptacle, whether canes root at the tip. Black Raspberry has small flowers with widely spreading petals, stems are covered in a waxy bloom and smooth except for scattered broad-based prickles, leaves are nearly all compound in 3s (rarely 5s) and silvery on the underside, the fruit does not easily separate from the receptacle, and canes are strongly arching and root at the tips. Contrast with Red Raspberry (Rubus idaeus), which is generally a smaller plant, primocanes with leaves mostly pinnately compound in 5s, lacks prickles but stems and stalks are glandular-hairy and bristly, fruit easily separates from the receptacle, and canes do not root at the tip.