Research Update on Crabgrass Control in Fescue
written by: Jared Hoyle, Travis Gannon, and Dr. Fred Yelverton
North Carolina State University - Department of Crop Science
Smooth and large crabgrass (Digitaria spp.) are common weeds in managed turf in North Carolina. Each year, homeowners and turfgrass managers must implement management plans for crabgrass species. Additionally, crabgrass control in tall fescue is extremely important as crabgrass species are summer annual weeds which are able to thrive when tall fescue is stressed. Most homeowners mow their lawn shorter than recommended. The close mowing causes scalping and puts stress on the fescue making it less able to compete with crabgrass species.
Field experiments were initiated in 2007 at Lake Wheeler Field Labs in Raleigh, North Carolina to determine if tall fescue mowing height could suppress crabgrass maintained as a home lawn. Large crabgrass was seeded in early March. Evaluated mowing heights included 1", 2", 3", or 4" and were initiated once soil temperatures reached an optimum for crabgrass emergence.
Trials were evaluated monthly for crabgrass incidence through September. By mid-September, 1", 2", 3", or 4" tall fescue mowing heights resulted in 95%, 48%, 13%, and 0% crabgrass cover, respectively. These data indicate increased tall fescue mowing height may culturally suppress crabgrass in tall fescue.
For More information visit the Weed Management Decision Aids enter Crabgrass weed in Tall Fescue Turfgrass.