smooth crabgrass

Smooth crabgrass (Digitaria ischaemum) is a weedy grass species that is a troublesome pest in lawns and fields, particularly in North America where it has become naturalized. It belongs to the genus Digitaria, which includes about 220 species of grasses.123

This annual or perennial grass spreads by seeds and vegetatively, with its decumbent stems rooting at the joints to form dense patches. Eradicating smooth crabgrass is challenging because mowing can encourage more flowering and seeding. While preemergence herbicides and hand weeding can help, a robust lawn that outcompetes crabgrass seedlings is considered the most effective control method.1