How to Identify Dallisgrass
Dallisgrass (Paspalum dilatatum) grows in distinctive clumps from a central root crown, producing coarse, wide blades that are darker green and taller than surrounding turf. The most obvious sign is the seed stalks: thin stems that shoot up 2 to 3 feet tall with dark seeds arranged in rows along 3 to 5 branches at the top.
The critical distinction from crabgrass: dallisgrass is perennial. It returns from the same root crown every year and doesn’t die in winter. Crabgrass is annual, dies at first frost, and spreads only by seed. If your “crabgrass” is in the exact same spot as last year, it’s probably dallisgrass.
Why It’s One of the Hardest Lawn Weeds
There is no effective selective pre-emergent for dallisgrass because it’s already established from its root system, not germinating from seed each year. Post-emergent options are limited: the most reliable approach is spot-treating individual clumps with glyphosate (which kills everything) and reseeding the bare spots.
Some selective products containing MSMA were effective but have been restricted for residential use by the EPA. Foramsulfuron (Revolver) provides selective control in some warm-season grasses but is typically professional-use only. For most homeowners, the dig-and-reseed or spot-spray approach is the practical option.
