How to Get Rid of Dallisgrass: 3 Ways to Identify Dallisgrass

Dallisgrass (Paspalum dilatatum) is a coarse-textured perennial grass that grows in round, tufted clumps. Native to Brazil, Uruguay, and Argentina, the grass is now an invasive species and pesky weed in North America, outcompeting homeowners’ lawns, commercial golf courses, and city landscaping for nutrients across much of the American South.

Other grassy weeds include crabgrass, Bermuda grass, and fescue weed.

Dallisgrass weed has a few key characteristics that make it easily identifiable, including:

• Clumping growth: Where healthy lawn grass will grow smooth and evenly, dallisgrass is a clumping grass that grows in uneven round patches. The growth pattern makes it easily distinguishable from lawn grasses like Kentucky bluegrass, St. Augustine grass, tall fescue, zoysiagrass, or rye.
• Wide leaf blades: Dallisgrass has relatively wide leaves, ranging between a ¼- and a ½-inch wide, giving it a broadleaf appearance similar to crabgrass rather than thin-leafed turf grasses.
• Shallow rhizomes: Examine the growth of the root system just beneath the soil surface to distinguish dallisgrass from other clump-growing weeds. Unlike other clumping grasses, dallisgrass sprouts from short, thick rhizomes underneath the ground. These rhizomes have a unique appearance—their internodes (or joints) look like tight, concentric circles of growth layered together.

Here’s a step-by-step guide to proper dallisgrass control:

1. 1. Manually dig out dallisgrass clumps: The most effective way to get rid of existing clumps of dallisgrass in your yard is to dig out each clump by hand or with a shovel. When digging up each plant, make sure that you dig underneath the plant to remove the rhizome from the soil, rather than pulling it out or trimming the leaves. New dallisgrass plants will be able to sprout if you leave any rhizomes in the soil.
2. 2. Sow a dense lawn: Once your yard is dallisgrass-free, you’ll need to take preventative measures to keep the plant from coming back. One of the simplest ways to prevent dallisgrass is to reduce bare spots in your yard. By planting a dense lawn or landscaping area, dallisgrass will not be able to find bare areas in which to take hold and sprout.
3. 3. Maintain your plants: Dallisgrass is an opportunistic weed, which means that it seeks out and thrives in locations where it’s easiest to steal nutrients and resources from weaker plants. If all of the plants in your yard are thriving, dallisgrass has a much harder time establishing itself. Choose plants and lawn grasses that will do well in your yard, and set up a regular lawn care schedule to mow, water, fertilize, and mulch.
4. 4. Consider herbicides if necessary: If your yard has a major dallisgrass problem and other methods aren’t working, consider a chemical weed killer to eradicate the weed. In general, landscapers recommend a combination of pre-emergent herbicides like dithiopyr and oryzalin (which target germinating rhizomes) and sprayer spot-treatments with post-emergent herbicides like CMA, glyphosate, foramsulfuron, or MSMA (which target established plants) to kill dallisgrass successfully. Perform herbicide applications according to the package instructions.

Dallisgrass and crabgrass are two perennial weeds that plague lawns, though they have a few major differences:

1. 1. Appearance: While dallisgrass is a tufted grassy weed that can grow several feet tall if left unchecked, crabgrass is a flat grower that often eludes the lawnmower, making it harder to use mowing as a quick fix.
2. 2. Germination: While dallisgrass seeds begin the life cycle for new plants, established dallisgrass spreads through short rhizomes, which are thick, root-like growths that spread beneath the surface of the soils. On the other hand, crabgrass grows from seeds shed during the growing season, experiencing major regrowth in early spring.
3. 3. Control: The difference in germination methods between dallisgrass and crabgrass is crucial for weed control. To control dallisgrass, you must dig up the rhizomes. To control crabgrass, you must pull the weed early to prevent it from shedding seeds. In addition to manual control, both weeds are sensitive to chemicals, including selective and non-selective herbicides.
4. 4. Response to fertilizer: Some landscapers recommend using fertilizer to get rid of crabgrass since it can be sensitive to nitrogenous fertilizers. However, dallisgrass doesn’t share this sensitivity, rendering fertilizing unhelpful as a method of removal.

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