A common garden weed
Annual Bluegrass, Poa annua, is a non-native species, often growing in sidewalk cracks, gardens, and other disturbed areas. It is an annual grass that does a good job of reseeding itself, which is why you can see it time and time again in the same spot. It is a cool-season grass that greens up in late winter and early spring.
This grass is short in size, grows in a dense clump, and produces fibrous roots, making it easier to weed than rhizomatous grasses. Like other bluegrasses, the leaves of Annual Bluegrass have a keeled, or boat-shaped tip. This means that the tip of the blade is shaped like the front of a kayak.
Annual Bluegrass produces a panicle inflorescence with pointed spikelets. If you're familiar with Kentucky Bluegrass, the inflorescence looks very similar.
The key to controlling this plant is to remove it before it sets seed.

