Crab Grass

The high survival and reproductive rate of crabgrass helps this weed sprout annually to spread up to 150,000 seeds in a season. Crabgrass has wide, flat leaves that form in a clump that can grow up to a foot in diameter. Healthy root systems and preventative pre-emergent applications can help protect a lawn from crabgrass growth. The cold temperatures of fall and winter kill the crabgrass but not its seeds. It is important to apply weed control once crabgrass is spotted to eliminate it before it fully grows and begins seeding.

Via greenteelawncare.com

Even with all the preventative maintenance there is always a chance of crabgrass sprouting. Crabgrass has excellent survival and reproductive qualities. A weed control application would be the most effective way to stop the crabgrass before it fully grows and begins seeding.