Control of Phyla Nodiflora

Description

• Matchweed, which takes its nickname from its flowers’ resemblance to a match head, is a creeping wildflower that forms thick mats. The plant grows to 3 inches in height, gaining another 3 inches when it’s bearing the tiny white flowers on tall stems that attract its fans. Matchweed will grow in just about any soil and tolerates short periods of drought. It is hardy in U.S. Department of Agriculture plant hardiness zones 8 through 11.

Herbicides

• To kill matchweed that is infesting lawns or ornamental beds, use a selective herbicide with 2,4-D, atrazine or simazine as the active ingredient, or a selective two- or three-way broadleaf weed killer. Selective herbicides kill only the plants listed on the label. Check the product’s label to ensure that it is safe to use on your turfgrass or near the ornamentals in your yard. Non-selective herbicides containing glyphosate will kill matchweed, but they will also kill other vegetation in the area -- so use these only where there are no desirable plants in the area.

Timing

• The best time to apply the herbicide is in spring, just after the lawn emerges from dormancy and while the matchweed is still small and growing. Choose a day when the temperature is expected to remain below 90 degrees Fahrenheit, unless the lawn contains bermudagrass, in which case the temperature needs to be no higher than 85 degrees Fahrenheit. Temperatures higher than this will cause a phytotoxic reaction with the selective herbicides -- the matchweed will die, but the grass may also be damaged. Sometimes new lawns become infested with weeds. If you are treating a recently planted lawn, wait until after the fourth mowing. Don’t use the clippings in the compost heap, but allow them to remain on the lawn. Reapply the herbicide in the fall to kill late-germinating matchweed seedlings.

Tools Required

• To treat small areas, use a pump-style sprayer. When treating large areas, a hose-end sprayer works best. Some of the commercially available hose-end sprayers come equipped with a dial that you can set to deliver a predetermined amount of the herbicide per gallon of water from the hose. Other hose-end sprayers require the gardener to add both the concentrated herbicide and the water to the tank before attaching it to the hose. Several herbicide manufacturers sell ready-to-use formulas with a hose attachment on the bottle.

Application

• Water the area the day before the herbicide application. If you’re using a pump-style tank sprayer, add the herbicide and water to the sprayer’s tank and swirl it to mix them together. Pressurize the sprayer and set the nozzle to deliver a coarse spray. Hold the nozzle 12 inches from the weeds and spray evenly. If you’re using a hose-end sprayer with a dial, pour the herbicide into the tank but don’t add water. Set the dial to deliver the appropriate number of ounces of herbicide per gallon of water. Hose-end sprayers without dials will have marks on the inside of the tank. Add the herbicide to the tank, then fill the tank to the 1-gallon mark with water. Put the top on the tank, shake it gently and attach it to the hose.

Precautions

• Wear protective clothing and avoid inhaling the herbicide during the application, and wash with soap and water immediately after applying the herbicide. Keep people and pets off the area until the spray dries. Avoid mowing the lawn for two days after the application and don’t use the clippings as mulch or in the compost pile from the next three mowings. If you need to make more than two applications per year, spot treat the weeds with the selective herbicide instead of applying the product to the entire lawn.