Ask the Experts

How to Identify and Control Dallisgrass in North Texas Lawns

Image Source: University of Missouri

Dallisgrass is one of the most aggressive and stubborn weeds in North Texas lawns. Known for its coarse texture and rapid growth, this perennial weed thrives in warm, moist areas and spreads quickly through both seeds and underground rhizomes. In the Dallas–Fort Worth area, where summers are long, Dallisgrass can easily overtake even well-maintained turf if not addressed early.

Whether you manage a residential lawn, HOA, or commercial property, learning how to identify and control Dallisgrass is key to maintaining a healthy, uniform landscape.

What Is Dallisgrass?

Is Dallisgrass a weed? Yes, Dallisgrass (Paspalum dilatatum) is considered a perennial grassy weed in North Texas because it invades turfgrass areas and forms unsightly clumps that disrupt uniform lawns.

Originally introduced from South America as a pasture grass, Dallisgrass quickly became invasive across the southern U.S. It thrives in moist, low-lying areas and compacted soils, particularly where drainage is poor or irrigation is frequent.

Is Dallisgrass a Problem in North Texas Lawns

Dallisgrass competes aggressively with desirable turf species like bermudagrass and zoysiagrass. It grows faster, taller, and in rougher clumps, creating uneven patches that ruin the smooth look of a manicured lawn.

Because Dallisgrass is a perennial weed, it survives winter and regrows each year from its deep rhizome system. In the DFW climate (mild winters and long growing seasons), that means it can spread rapidly both by seed and underground stems, making it difficult to eliminate once established.

Left unchecked, it can:

  • Outcompete turfgrass for water and nutrients
  • Form dense clumps that damage mowing equipment
  • Create uneven, patchy surfaces on sports fields and commercial properties

How to Identify Dallisgrass in Your Lawn

Image Source: University of Missouri

How can you tell if you have Dallisgrass or crabgrass?

While both are common summer weeds, Dallisgrass is a perennial with thicker clumps and seed heads that persist year after year, unlike annual crabgrass, which dies off each fall.

Here’s how to recognize Dallisgrass:

  • Growth Habit: Forms coarse, circular clumps that spread outward via rhizomes.
  • Leaves and Stems: Wide, flat blades (¼ to ½ inch) with a rough texture and prominent midrib.
  • Seed Heads: Tall stalks with two to five finger-like seed spikes, often dotted with black specks from a smut fungus.
  • Roots: Deep, fibrous root system with creeping rhizomes that allow regrowth even after mowing or partial removal.

How to Prevent Dallisgrass in North Texas

Can you prevent Dallisgrass before it grows?

Yes, the best way to manage Dallisgrass is through prevention before seeds germinate or rhizomes spread.

  • Apply Pre-Emergent Herbicide: Use a pre-emergent product containing dithiopyr or prodiamine in early spring (February–March) before soil temperatures reach 55°F.
  • Improve Drainage: Dallisgrass thrives in wet areas. Ensure proper grading and avoid overwatering to discourage growth.
  • Aerate the Soil: Annual aeration improves soil structure and reduces compaction, making conditions less favorable for Dallisgrass.
  • Maintain Turf Density: Overseed bare patches and fertilize appropriately to help turfgrass outcompete weeds.

How to Control Dallisgrass If It’s Already Present

Can Dallisgrass be killed without killing your lawn?

Unfortunately, Dallisgrass is difficult to remove selectively once it’s established because few herbicides target it without harming warm-season turf. However, with persistence, control is possible.

Here are your options:

  • Spot Treatments: Use a non-selective herbicide (such as glyphosate) to carefully treat individual clumps, then re-sod or overseed the area once the weed dies.
  • Manual Removal: Dig out Dallisgrass by hand, ensuring you remove the entire root and rhizome system. This is easiest after rainfall or irrigation when the soil is soft.
  • Professional Applications: Lawn care professionals can apply targeted herbicide programs over multiple seasons for best results.

Keep Your Lawn Healthy with the Right Weed Prevention Strategy

Because Dallisgrass is one of the most persistent grassy weeds in Texas, it often requires ongoing, professional management.

Maintaining a healthy, weed-free lawn requires a proactive approach. By applying pre-emergent herbicides at the right times and following proper lawn care practices, you can minimize the chances of this persistent weed—and others—taking over your lawn. With help from an expert team like Southern Botanical, you can achieve a lush, beautiful lawn that remains resilient through every season.