General Description:
The subspecies Poa annua ssp. annua is an upright, clump-forming, winter annual. Poa annua ssp. reptans is a prostrate, clump-forming perennial. Both may grow up to 12 in (30 cm) in height, and both tolerate close moving. Both are light green and are prolific seedhead producers.
Seedling: The first leaf blade is linear and very narrow, about 30 times longer than wide, and open perpendicular to the ground. Leaves are light green, folded in the bud, lack auricles, and have a slightly pointed membranous ligule. Blade are 3/4 to 2 in (2 to 5 cm) long and 1/36 to 1/16 in (0.7 to 1.5 mm) wide, hairless, keeled, with a curve prow-shaped tip and smooth margins. Blades can also be rippled or wrinkled. Sheaths are compressed and hairless. The collar is green and smooth. Mature Plant: Leaves and ligule are similar to those of the seedling. Blades are 1/3 to 6 in (1 to 14 cm) long by 1/25 to 1/8 in (1 to 3 mm) wide, light green, smooth, and keeled, with curved prow-shaped tips. Sheaths are loose, smooth, slightly compressed and keeled. The collar is smooth and narrow. Flowers and Fruit: Plants flower from April through October. The seedhead is an open greenish white pyramidal panicle. Spikelets produce 2 to 6 flowers. Distribution: Found throughout the United States and Canada Crops Affected: Wheat Animal Poisoning: None Similar Species: Canada bluegrass and Kentucky bluegrass are both rhizomatous perennials and tend to be darker than annual bluegrass. Annual bluegrass may root at the nodes but is not rhizomatous.