Florida weed with sticky sharp seeds

Tattnall County Extension

Local News for 4-H, Agriculture, and Family and Consumer Science

Ouch! What is that weed in my lawn?

Burweed is a common weed in our lawns that produces sharp “burrs” that can stick in your feet. It hurts!

We often get several calls in the spring about a weed that comes up in our lawns that has sharp “burrs” or “stickers” that hurt our feet if we walk outside barefoot. Some people call it stickerweed or spur weed, and if you ever step on it without any shoes on, you may call it something else that I can’t put in the paper! This weed is officially known as burweed, and it can be a big nuisance to people and pets. Burweed is a winter annual, which means that it germinates from seed and begins to grow in the Fall or Winter. It is a low growing weed that will often come up in bare or thin spots in our grass. Winter annuals like burweed will often begin to die off in the late spring or summer, but not before they produce their seed for the following season. In the case of burweed, their seeds are produced within the sharp burrs that cause so much pain when stepped on!

The problem with burweed is that when we get calls about it, it is often too late to do anything. If you have the burrs in your yard, the burweed has already gone to seed (the sharp burrs!) and there is not much you can do or spray to get rid of those burrs. The best method to control it is to spray a post emergence herbicide that is safe for your lawn in December, January, or February. If you have centipede grass, something like atrazine or metsulfuron will kill this weed. These products may also help to kill the burweed at this time of year, but the burrs will still remain and be the seed for next year’s problem.

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So, if you are having trouble with this weed, you can try to control it now if you’d like, but make a mental note to spray for it next winter. Watch where you step!

Here’s a close up of burweed. You can see the burrs there above my thumb.

Lawn burweed: What is this weed with sharp spurs in lawns?

The weed in question is most commonly lawn burweed (Soliva pterosperma), a.k.a. spurweed, stickerweed, sandbur, sanbur and sandspur. Lawn burweed is a winter annual member of the Aster family. The weed germinates in the early fall months as temperatures cool and remains small or inconspicuous during the cold winter months. However, as temperatures warm in the early spring, or about the same time as spring sports activities, lawn burweed initiates a period of rapid growth and begins to form spine-tipped burs in the leaf axils. The sharp-tipped spiny burs of this weed can irritate the skin.

Key identification characteristics of lawn burweed are:

  • opposite, sparsely hairy leaves that are divided into numerous segments, or lobes
  • small, inconspicuous flowers, and c) spine tipped burs that are found in the leaf axils (junction of leaf and stem).
  • attains an overall diameter of up to 6 inches and a height of about 3 to 4 inches.
  • It is commonly found in the Coastal Plain and Piedmont regions of Georgia.

Lawn burweed is easily controlled during the winter months.

December, January and February are ideal months to apply herbicides to control this weed. Lawn burweed is small and easier to control at this time of the year than in April and May. Also, turfgrasses are not actively-growing during the winter months and have better tolerance to some herbicides.

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See the UGA Pest Management Handbook for pesticide recommendations for your turf type. Two to three weeks after the initial application, lawn burweed control should be evaluated. If control is not acceptable, an additional application may be necessary.