Springtime often sees large outbreaks of a little lawn weed with stickers on it. And although some call it "sticker grass," it's not a grass, according to LSU AgCenter horticulturist Dr. Tom Koske.
"The weed looks more like a frilly leaved parsley," the horticulturist says, adding, "It is the winter annual Soliva pterosperma, commonly called lawn burweed or spurweed, a member of the aster family."
The weed first germinates around Baton Rouge about late September and is mostly gone by mid June, Koske says.
In the New Orleans area, the plant starts growing a week later than in Baton Rouge and fades a week earlier the next year. In the Shreveport area, it germinates around the first of September and is gone by July.
"It grows slowly until early spring," Koske explains. "When it activates, spurweed grows rapidly and forms spine-tipped, green flower burs at each leaf base."
The plant is usually especially bad along paths and in thin turf areas. As the flowers mature, the spines get tougher and more bothersome.
"Lawn burweed can easily be controlled," Koske says, noting, "With a thick, healthy turf, you may never see this problem."
The LSU AgCenter horticulturist recommends preemergence herbicides to control lawn burweed before it germinates in early fall. In late winter or spring, he suggests applying atrazine, simazine or Image to non-overseeded turf. Other postemergence options include Confront products with 2, 4-D and dicamba.
Koske says spurweed begins to die as temperatures reach 90 F.
"Most mature plants are harder to kill, and even dead, mature weeds still have prickly spines," he says, adding, "So for best results, control it before it flowers or wait until next fall."
Related yard and garden topics are available by contacting an extension agent in your parish LSU AgCenter office. Also, look for Gardening and Get It Growing links in the Feature section of the LSU AgCenter Web site: www.lsuagcenter.com.
The LSU AgCenter and the LSU College of Agriculture