dallis grass
Family
PoaceaeScientific Name
Paspalum dilatatumOther Common Names:
water grass
Habit
Dallisgrass is a clumping perennial grass that spread from short thick rhizomes. Plants emerge in spring and early summer and bloom from midsummer to early autumn.
Leaves
At seedling stage the first few leaves may have short soft hairs; however, after that point, there are only long hairs present on the plant located at the collar region and hairs along the leaf margin. Leaves are 0.25 to 0.50 inches wide and 4 to 10 inches long. It is pretty normal for the base of the grass stems to be purple. Mature plant has smooth sheaths and a tall membranous ligule (5mm). The leaf also has a prominent mid vein.
Identifying Characteristics
Dallisgrass has very strong prostrate tillers that do not root at the nodes. It also has short, shallow running rhizomes. The mid-rib helps distinguish between weeds like crabgrass and foxtail.
Flower Seed Head
Dallisgrass has a very distinct seedhead and is easily identifiable. Seed head is raceme, and has hairy spikelets. Flowers are produced on a tall terminal stalk that has 3-5 or more branches (2-3 inches in length) along the terminal end. The spikelets are ovate, wide, and covered in soft hairs. There are four rows of them, one each raceme.
Seed Fruit
The seeds are ovate, shiny and yellow to brown in color. Black anthers often persist as fruit mature giving the seedheads a characteristic look.
Where Found
This is a major turf weed, but also invades flower beds, pastures, and road-sides. While it can grow in many habitats it prefers moist conditions.
Leaf Hair on Upper Surface
no hairs
Mature Leaf Width
6 to 15 mm
Stem
flat or oval
Seedhead
multiple spikes
Root Structure
fibrous
Life Cycle
perennial
Auricle
not present
Ligule
membrane
Ligule Length
more than 3 mm
Plant Type
Grass