Definition
Refers to a grass-like plant that is often the target of weed control programs because its creeping stems root freely throughout lawns. In order to grow, crabgrass requires lots of sun. That's why taller grass may provide the best weed prevention by shading any crabgrass seeds. Also, overseeding a lawn will be easier in non-summer months when new grass seeds won't be competing with weeds and crabgrass.