Lawn & Garden
AUBURN UNIVERSITY, Ala. – Pesky weeds will damper any happy, summer day. Finding effective solutions can seem nearly impossible.
According to Alabama Extension Regional Agent David Lawrence, dallisgrass and wild violets can be two of the most difficult weeds to control in warm-season turfgrass. As perennial weeds, they are common throughout Alabama. Don’t fret; Lawrence shares possible solutions to remove dallisgrass or wild violets.
Dallisgrass is a coarse, clumping grass. Not to be confused with crabgrass or other warm-season grass weeds, dallisgrass often grows in a circular pattern.
“The easiest way to identify dallisgrass is by the seed head,” Lawrence said. The seed head can grow two to three feet tall and will have three to five alternating spikes.
Wild violet is a low growing broadleaf weed with glossy, heart-shaped leaves. These plants often form small purple, blue or white flowers in the spring.
Wild violets are most often found in areas with abundant shade and excess moisture.
First Line of Defense
“The first line of defense against weed pressure is to produce a healthy turf,” Lawrence said. “Many weed issues can be resolved with proper fertilization, irrigation and mowing.”
If the first line of defense is not enough, chemical control may be necessary.
All weed control programs begin with a good pre-emergent herbicide. “Indaziflam and prodiamine are two pre-emergent products that are commonly used in warm-season turfgrass,” Lawrence said.
Application should take place in the spring and fall prior to weed seed germination. Unfortunately, these products will not control weeds that are already present.
For full-grown weeds, post-emergent herbicides are necessary. Since dallisgrass is a grass and wild violets are a broadleaf, they may require different chemical control.
Dallisgrass Post-Emergent Herbicide
“Monosodium methanearsonate (MSMA) was used for several years for dallisgrass control and is currently labeled for use on sod farms and golf courses,” Lawrence said. “However, it is not labeled for home lawns.”
Herbicides containing sulfonylureas such as Celsius, Tribute Total and Monument have shown activity against dallisgrass. It is best to apply these products as multiple spot treatments in early to late fall.
Wild Violets Post-Emergent Herbicide
Controlling wild violets is best using post-emergent broadleaf herbicides. Products often found in broadleaf weed control mixtures for warm-season turfgrass include 2, 4-D, dicamba, mecoprop (MCPP) and carfentrazone.
Like dallisgrass, it may require multiple applications for complete control.
If you prefer to not use chemicals for removal, hand removal is an option. However, for hand removal to be effective, you must remove the entire rhizome. Otherwise, the weed will simply re-emerge.
Weed removal, especially dallisgrass and wild violets, is often trial and error. Discover which method works best for you and your yard.
For more information on weeds, visit the Alabama Extension website, www.aces.edu.
Trade and brand names used in this article are given for information purposes only. No guarantee, endorsement, or discrimination among comparable products is intended or implied by the Alabama Cooperative Extension System.