WEEDS TO WEED OUT NOW
By Marigay Black
Grayson County Master Gardener
August 29, 2020
One morning last fall, I looked out in my yard and saw a sea of little white flowers with yellow centers growing in an area which, I admit, rarely received supplemental watering. I’ve seen this plant before and not been too concerned by it. The bees were drawn to it, and I like supporting our bees with nectar plants, so we just mowed the grass and let nature take its course. This fall, the plant has returned en masse and I have declared war on it – and it’s one tough plant! It is unpleasant to walk on the woody stems and puts down a taproot to ensure its place in the soil. It is roadside aster (Aster exilis), an annual that will reseed with a passion if those blooms are allowed to go to seed (again).
It sneaks into your bermudagrass because the tiny new plants that come up in the Spring blend in perfectly with the stems of the grass. By the time you realize how much is there, it is a rough-stemmed plant intertwining with your bermuda. It’s getting ready to bloom now!
My online research has directed me to three different approaches to wage my war. The first, and most labor intensive, is to pull it by hand or with a good weed-pulling tool. By watering the area first, the plants will come up fairly easily and it’s a goner for good. So far, I’ve filled three 5-gallon buckets, and there will be several more to fill. The drawback is that, once pulled, it leaves a pretty good sized bald spot where the bermuda will have to fill in and we’re getting close to the end of growing season for bermuda.
The second front to launch on the mature plant is the use of a broadleaf and woody weed killer containing the chemical 2,4-d. There are several name-brand products in liquid, dust or granular form that you apply accordingly. 2,4-d is labeled to kill many different types of broadleaf weeds such as crabgrass, for one, but it also listed many desirable plants such as goldenrod. The labels also warned the user that the product should not be allowed to enter water streams and don’t allow it to overspray or drift onto other plants or outside of your property. I prefer to avoid the use of chemicals with a warning label as serious as the ones I read standing in the aisle of the gardening center.
The third front to wage my battle is to apply a cool season pre-emergent NOW. There are several brand names to choose from which come in liquid and granular form containing the active ingredient dithiopyr. There are warnings outlined on these product labels which must be considered carefully. A pre-emergent acts to stop the seed of various labeled plants from germinating so they don’t get a chance to invade your lawn.
The last piece of advice to win this war is to take better care of the bermudagrass during its growing season, and the roadside aster won’t have such an easy time making its way into my lawn. The grass needs to be fertilized according to its season, watered on a regular basis, and mowed to its recommended height to fill in all the spaces that weed seeds would like to fill.
Grayson County Master Gardeners Association is a non-profit 501(c)(3) organization sponsored by the Texas A&M AgriLife Extension Service. Reach us by email at firstname.lastname@example.org, by phone 903-813-4204, our web page txmg.org/grayson, or our Facebook group.