Brownwood Lawn Owners Face a Persistent Summer Problem: How to Stop Sandburs and Grass Stickers

Brownwood homeowners battling painful sandburs, also known as grass stickers, may need more than a single weed treatment to solve the problem. Texas A&M AgriLife Extension turfgrass specialist Pablo Agustin Boeri recommends matching control efforts to the plant’s life cycle, timing preemergence herbicides carefully, removing established plants and maintaining dense, healthy turfgrass.

Sandburs are weedy grasses that produce sharp, barbed seed pods. The pods attach to shoes, socks, pet fur and bare feet, creating a particular concern for children and pets who play outdoors. The plants can also be difficult to eliminate because their seeds may remain dormant in soil for years before germinating.

Why grass stickers keep returning

Sandbur seeds spread when the burs cling to people, animals or clothing. Depending on the climate and type of sandbur, the plant may behave as a summer annual, survive the winter as a living plant or go dormant and return in spring.

That life-cycle difference affects both treatment and timing. The source article notes that sandbur pods contain two kinds of seeds with different dormancy periods, allowing germination to continue for three years or more. Some seeds can remain dormant in soil for as long as eight years.

“Sandburs, like many other weeds, are opportunistic, and we need to keep that in mind when we try to control them,” Boeri said. “Usually, we want to remove weeds from a lawn for aesthetics, but sandburs can be a health concern, especially for children and pets.”

Four steps for controlling sandburs

1. Match treatment to the local growing cycle. Sandburs can begin germinating when soil temperatures reach about 52 degrees, although emergence continues at lower levels through the summer. The largest wave of emergence occurs when soil temperatures reach approximately 72 degrees, and plants that emerge during that period generally produce the most burs.

2. Apply preemergence herbicide before peak emergence. Preemergence products prevent new seeds from sprouting but do not kill plants that have already emerged. Boeri recommends applying a product before the peak emergence window and making a second application according to the product label, soil type and weather conditions.

Active ingredients identified in the source include dithiopyr, indaziflam, oryzalin and pendimethalin. If a few plants appear after treatment, homeowners can remove them by hand or mechanically, or use a post-emergence herbicide. Remaining plants could also indicate herbicide resistance, according to Boeri.

3. Use an appropriate post-emergence product. Many post-emergence herbicides sold in retail stores are not labeled for sandburs. The source identifies imazaquin as the most accessible post-emergent option for homeowners, with products available online and through many home and garden retailers.

Some professional products containing flazasulfuron, or a combination of thiencarbazone, iodosulfuron and dicamba, may be effective but are intended for licensed commercial applicators. Flazasulfuron is limited to Bermuda grass and zoysia grass, according to Boeri.

For lawns with established sandbur populations, combining pre- and post-emergence treatments can help. The preemergence application limits new plants, while the post-emergence treatment addresses plants that were missed. After established plants are controlled, Boeri recommends continuing a preemergence program during spring and summer.

Homeowners should read and follow every product label and calibrate application equipment carefully. Herbicide selection and use should also account for the type of turfgrass being treated.

4. Fill open lawn space with healthy turfgrass. Boeri describes dense, healthy turfgrass as the best long-term defense because sandburs take advantage of bare or weak areas. Sandburs can grow in poor soil, while many turfgrasses need fertile soil, so a soil test can help identify what the lawn requires.

The local AgriLife Extension office can provide a soil test kit and instructions for collecting and mailing a sample. Homeowners can then follow fertilization and lawn-care recommendations suited to their soil and grass species.

Watering and mowing can affect next year’s problem

Watering too early in the season or too often can produce shallow roots, weaker turfgrass and greater vulnerability to disease and drought. Homeowners seeking weather-based irrigation guidance can use AgriLife Extension’s free WaterMyYard app if their area is covered, or consult the agency’s lawn-irrigation resources.

Mowing height and frequency should be adjusted for the grass species. Cutting the lawn too short, or scalping it, opens space for sandburs to germinate. Bermuda grass and St. Augustine grass, for example, require different mowing heights.

When sandburs are producing seeds, homeowners should bag and dispose of grass clippings instead of leaving them on the lawn. That practice can reduce the number of sandbur seeds added to the soil for the following year, as well as limit the spread of other weeds.

“Consistent practices that make your lawn a place where turfgrass thrives makes it difficult for sandburs,” Boeri said. “As much as we hate grass stickers, these weeds hate a healthy lawn.”