Q: What is this weed in my bermuda lawn?

A: It’s crabgrass.

The best way to control it is to apply a weed preventer (click for sources) in early spring.

The exact timing depends on soil temperature. When soil is 50 degrees F. and rising, crabgrass seeds start germinating. This soil temperature typically occurs in early March in the Atlanta area but there is no harm in applying pre-emergent in mid-February.

Once you see sprouts, the weed is difficult to control in your lawn. Seeds may lie dormant for up to three years, so yearly vigilance is key.

Crabgrass starts shedding seed in early June, so prevention is BY FAR the best option. The plant will die in fall, leaving hundreds of seeds to sprout next year if not controlled.