Sticker burrs (Cenchrus echinatus), also called sandburs or grass burrs, annoy you and your pets as the small, prickly seed casings stick to your clothes or your pet’s fur. They might even stick your fingers as you remove them. These annuals grow in southern and western states, thriving in warm and Mediterranean climates. A yard full of sticker burr weeds isn’t desirable, but there are several ways to keep the weeds away.
These chemicals may be harmful to pets, people and the environment in general, so read the package label carefully before purchase to ensure it suits your needs. If you do purchase a chemical-based burr killer, read the label again before application to make sure you apply it properly. Wait the allotted time after application before allowing pets or people to walk upon the lawn.
Problems With Sticker Burrs
Pre-emergent herbicides can nip a potential burr weed problem in the bud. Spreading a weed-and-feed product helps build stronger turf while keeping the weed seeds from germinating. However, this works best when applied about two weeds before the soil reaches the optimum temperature, so this might not fit in with your fertilization schedule. Other pre-emergent herbicides, such as benefin and oryzalin, work to kill the weeds before they sprout. Water these granulized herbicides into the soil for maximum effectiveness. Reapply a pre-emergent herbicide every six weeks to keep new seeds from germinating.
Keeping a lush, healthy lawn prevents most sticker burr weed seeds from getting a foothold. Use a nitrogen-rich fertilizer, such as a 21-0-0, on your lawn to encourage blade growth. Mow the grass with a high mower blade, such as 2 1/2 or 3 inches, and use long, deep waterings a couple of times a week rather than watering your grass just a little every day. This encourages thick blade coverage and deep root systems that keep sticker burr seeds from germinating properly.
Attacking the sticker burr weeds while they’re young, before they develop seeds, is the best time to kill them after they emerge. Use a ready-to-use spray containing disodium methanearsonate, known as DSMA, or monosodium acid methanearsonate, called MSMA. If you buy a concentrate, mix about 1 ounce of MSMA or 3 ounces of DSMA per gallon of water before spraying your lawn. These herbicides are designed to kill the weeds without harming your lawn.
We’ve all been there. Spring arrives and our grass is becoming that green carpet in which you love to spread your bare toes. But what have we here? Sticky spurweed (Soliva sessilis) plants and other weeds are competing with your lawn. Lawn spurweed is an equal opportunity pest plant that occurs in most regions of the United States. It is quite invasive and is prickly and painful on your feet and legs. A little knowledge on how to kill spurweed will help protect your lawn from this nasty weed and spare tender skin from its burs and barbs.
You can use a pre-emergent herbicide in early October to early November before the seeds have germinated. A post-emergent application should wait until you see the tiny parsley-like plants, which is usually January or February. Once you have identified them, you can use formulas of Dicamba, 2, 4D, or MCPP. Follow the directions carefully for a two- or three-way mixture as recommended by the manufacturer.
Lawn Spurweed Information
Spurweed is predominant in the warmer climates of the United States and emerges in winter as an annual plant. In late spring, the real nuisance begins when the plant sets fruit. The fruits are similar to small cones and are barbed and spiny. Once the little cones are formed, the plant has plenty of seed to set for the next year’s crop and you are stuck dealing with it for another season. Spurweed control will have to wait until the coming fall when plants emerge.
Choose a windless day when spraying where temperatures are 55 degrees Fahrenheit (12 C.) or above. Make sure children and pets are not in the area when spraying. St. Augustine and Centipede grasses will require a more diluted application to prevent killing the sensitive grass. Some post-emergent herbicides will require a second application in two weeks.
A better method for eliminating spurweeds is to use an appropriate post-emergent herbicide in winter or a pre-emergent one in fall before germination has occurred. That way you can hit the plants before they form the damaging seed heads or cones. There are several formulas for spurweed control but they all rely on control when the plant is young.