How to Kill Dallisgrass
How to remove dallisgrass from your lawn. Spot treatment with glyphosate, digging methods, and reseeding bare spots.
For fewer than a dozen clumps, digging is effective and avoids herbicide. For larger infestations, spot spraying with glyphosate is more practical. Both methods kill surrounding grass in the immediate area, so plan to reseed regardless.
Use a flat shovel to cut a circle 4 to 6 inches around the clump and 4 inches deep. Lift out the entire root crown and surrounding soil. If any root crown piece remains in the ground, the clump regrows. Fill the hole with topsoil and reseed.
Apply glyphosate (Roundup or equivalent) directly to each dallisgrass clump. Use a foam marker or dye to track which clumps you've treated. Glyphosate is non-selective and kills everything it touches, so spray carefully. Shield surrounding grass with cardboard if clumps are near desirable turf.
Treated dallisgrass takes 10 to 14 days to fully die. The clump yellows, then browns. Do not reseed until the clump is completely dead. If you see any green regrowth after 3 weeks, apply a second treatment.
Fill bare spots with topsoil if needed, then overseed with your lawn grass type in early September. Water lightly twice daily until germination (7 to 14 days). A thick stand of new grass in the bare spots prevents dallisgrass seeds from germinating in those areas next spring.
