Every year between April and May homeowners ask what they need to do to get rid of the stickers in their yard. Stickers, also known as burweed (Soliva sessilis) is a winter or cool-season, annual broadleaf weed that spreads across the lawn through seeds. If you did not apply pre-emergent herbicides to your lawn in the fall, you can probably find it in the lawn now. Burweed seeds germinate in the fall and grow slowly during the winter months. Young burweed leaves resemble parsley leaves.
Burweed becomes a nuisance in the spring as temperatures warm. During this time growth accelerates and plants form spine-tipped burs that contain seeds near the base of the leaves. This is when people start to notice the presence of painful sticker weeds in their lawns. Unfortunately, burweed is nearly impossible to control at this point. Typically, multiple herbicides applications are only marginally successful at killing burweed once plants have set burs. Additionally, killing burweed after it has produced burs will not remove the painful stickers from your lawn, as they persist on dead plants.
If you applied a pre-emergent lawn herbicide in the fall, you are a step ahead in the battle to reclaim your lawn from a sticky situation. However, this is only part of the battle. If you didn’t put out a pre-emergent herbicide, all is not lost, there is still a window of opportunity, but it is closing fast.
Weed prevention for late winter and spring weeds begin in the fall with applications of pre-emergent herbicide which keep weed seeds from establishing. This is not a one and done solution though. Pre-emergent herbicides are not 100% effective, and you will need to apply post-emergent herbicides between late-January and mid-February to catch the seeds that did manage to germinate.
For post-emergent control of winter broadleaf weeds including burweed, henbit and chickweed, use products containing a combination of 2,4-D, mecoprop, and dicamba – commonly sold in a three-way formulation. These are generally safe for use in Centipede, St. Augustine, Bermuda, Zoysia, and Bahaigrass. Activity is better when temperatures are above 60F. Do not apply 2,4-D products to actively growing grass when temperatures are over 85F. Products containing Metsulfuron can also be used to control broadleaf weeds. Metsulfuron should not be used in Bahaigrass and be careful when applying around ornamental plants. Atrazine is an effective early post-emergent control that is safe for use on Centipede, St. Augustine, and dormant Bermudagrass.
This is also the time to apply pre-emergent herbicide treatments to prevent crabgrass seeds and other warm season lawn weeds from germinating. For pre-emergent control of crabgrass and other warm season weeds, use products with triflualin and benefin; dithiopyr; or pendimethalin. Make applications between now and mid-February, before crabgrass seeds germinate.
Do not apply fertilizers to your warm season turfgrass until it is actively growing – around mid-April for our area. Applying fertilizers too early can make turfgrass more sensitive to late season cold damage and lead to increased disease issues when the temperatures warm up. It is better to wait and to not overfertilize your lawn. If you haven’t had your soil tested in several years, now is a good time to do that to determine if you need to make corrections for soil pH or nutrient deficiencies.
Late winter is a good time to clean up your lawn by raking out excessive thatch. Reducing thatch build-up improves root health by allowing water and fertilizers to move into the root zone of the lawn. Removing excessive thatch can decrease disease and insect pressure as well.
When it comes to mowing your lawn, don’t forget about proper lawnmower maintenance. Sharp blades are a must. Also, pay attention to cutting height. Cutting grass too low can lead to problems with weeds and disease. Maintain St. Augustine at 2.5 to 3.5 inches, centipede and zoysia lawns at 1 to 2 inches, and Bermudagrass at 0.5 to 1.5 inches.
Taking care of a few lawn chores now will help prevent a sticky situation this spring.
