How to Kill Mare's-tail Weed
- 1). Pull up any existing mare's-tail weeds in your yard by hand. Get up as much of the root system as possible. If the weeds are mature and do not come up easily, use a hand spade to dig them out.
- 2). Discard the weeds in the trash. Do not compost the weeds, because you may spread dormant seeds with the compost in the future.
- 3). Till the soil with a garden tiller at a depth of 12 inches. Tillage is the most effective method of mare's-tail control.
- 4). Apply a metribuzin herbicide to any regrowth that appears the following spring. Follow application instructions on the package. Apply the herbicide when the mare's-tail is 4 inches tall or less. Wait the instructed time for the herbicide to take effect, then till the soil again.
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