Anyone who has ever walked barefoot across a lawn and stepped on a grass sticker knows just how much misery can come from such a tiny plant.
Sandburs, commonly called grass stickers or grassburs, are weeds that produce sharp, barbed seed pods capable of sticking to shoes, clothing and pet fur — and painfully finding bare feet. For households with children and pets spending time outdoors, a bad sandbur problem can turn a backyard into something closer to an obstacle course.
Fortunately, homeowners can fight back.
According to Texas A&M AgriLife Extension turfgrass specialists, controlling sandburs requires a combination of good timing, proper weed control and, perhaps most importantly, maintaining a healthy lawn.
Why Sandburs Keep Coming Back
One reason sandburs are so difficult to eliminate is their ability to spread and survive. The burs easily attach themselves to people and animals, allowing seeds to travel from one part of a yard to another. Even more frustrating, sandbur seeds can remain dormant in the soil for years before germinating.
Depending on the climate and type of sandbur, the plants may behave as annuals that return from seed each year or survive as perennials. In warmer areas, some plants may survive the winter and begin growing again when conditions improve. That means eliminating the plants you see this year doesn’t necessarily eliminate the problem waiting beneath the soil.
Stop Sandburs Before They Sprout
Preemergence herbicides can help prevent sandbur seeds from developing into new plants, but timing is important. Sandbur seeds can begin germinating when soil temperatures reach about 52 degrees, with the heaviest emergence occurring as soil temperatures approach 72 degrees. Applying an appropriate preemergence herbicide before that peak germination period can significantly reduce the number of plants that appear.
Texas A&M AgriLife Extension recommends homeowners look for products containing active ingredients such as dithiopyr, indaziflam, oryzalin or pendimethalin. Because sandburs can continue germinating throughout the growing season, a second application may be necessary depending on the product, soil conditions and weather. Always follow the herbicide label regarding application rates, timing and which turfgrass species can safely be treated.
What About Sandburs Already Growing?
Preemergence products won’t kill sandburs that have already emerged. Existing plants may need to be removed by hand or treated with an appropriate post-emergence herbicide. For homeowners, products containing imazaquin are among the more readily available options labeled for sandbur control.
Other herbicides used by professional applicators may also be effective, but some are restricted to particular turfgrass varieties or intended for commercial use. Homeowners should carefully check product labels before applying any herbicide. A product that works safely on Bermuda grass, for example, may not be appropriate for St. Augustine or another type of lawn.
Your Best Defense Is a Healthy Lawn
Herbicides can help control an existing problem, but the best long-term defense against sandburs may be something much simpler: healthy grass. Sandburs are opportunistic weeds that thrive in thin lawns, bare patches and poor soil. Dense turfgrass leaves fewer openings where weed seeds can germinate and establish themselves.
A soil test is a good place to start. Testing can identify nutrient deficiencies and soil conditions that may be preventing turfgrass from growing properly. Homeowners can then fertilize and amend the soil based on what their lawns actually need rather than guessing.
Local Texas A&M AgriLife Extension offices can provide information about soil testing, sampling and lawn-care recommendations appropriate for the area.
Don’t Overwater — and Don’t Scalp the Lawn
Everyday lawn-care habits can also make a difference.
Overwatering encourages shallow roots and can leave turfgrass more vulnerable to disease, drought and weed invasion. Instead of watering automatically on a fixed schedule, homeowners should irrigate based on the needs of their grass and current weather conditions.
Mowing height matters as well.
Cutting grass too short can weaken the turf and expose soil where sandbur seeds can germinate. Different grasses require different mowing heights, so homeowners should know what type of turfgrass they have and maintain it accordingly.
When sandburs are actively producing their painful little weapons of backyard warfare, homeowners should also consider bagging grass clippings rather than leaving them on the lawn. Removing clippings containing burs can help reduce the number of seeds being returned to the soil.
Winning the Grass-Sticker War Takes Time
A lawn with an established sandbur population probably won’t become sticker-free overnight. Seeds already in the soil can continue creating problems for several years, making consistency important.
A combination of properly timed preemergence treatment, control of existing plants, appropriate watering and mowing, and improving the overall health of the turf can gradually reduce the sandbur population.
And there is a pretty good reward for sticking with it: a backyard where children can play, pets can romp and adults can walk outside barefoot without suddenly discovering just how many creative words they remember.
For additional information about controlling sandburs or caring for Texas lawns, homeowners can contact their local Texas A&M AgriLife Extension Service office.
