If you had lawn burweed (Soliva pterosperma) last summer, but did not apply a pre-emergent herbicide in the fall, then you most likely have them again now. Commonly called sticker weed, lawn burweek will produce painful spines that you will have to endure each time you walk barefoot on your lawn...unless you take immediate action to control them now.
Lawn burweed is best described as a low-growing, freely branched winter annual having leaves that are twice divided into narrow segments, or lobes, similar to the appearance of carrot leaves but much smaller. The real identifier is once the plant reaches a reproductive stage the small fruit clusters, small rosette buttons, begin to form down in the leaf axils. At the tip of each seed within the cluster is a tiny spine that eventually dries at maturity and is what is left to cause you pain as they stick into tender flesh of bare feet, knees, hands, or whatever parts of the body that may come in contact with them.
If your lawn is presently infested with lawn burweed, and the fruiting clusters have not yet formed, you should act immediately to control them. Once the fruiting clusters have formed, and produced the tiny seeds and spines, killing the plants will eliminate the weeds, but the tiny spines and seed will remain to inflict pain for another summer.
MSU Extension publication, "Weed Control Guidelines for Mississippi" provides a list of several good post-emergent herbicide choices that will control this weed along with most other winter annual weed species, but timing is critical. This publication and others pertaining to weed control and home lawns can be downloaded from the Extension Web.
Published February 13, 2006
Dr. Wayne Wells is an Extension Professor and Turfgrass Specialist. His mailing address is Department of Plant and Soil Sciences, Mail Stop 9555, Mississippi State, MS 39762. firstname.lastname@example.org