Did you know that fall is the perfect time to treat for spring weeds? Summer herbicide applications have likely burned down top growth, but weeds will reappear once air and soil temperatures start to drop. With warm days and cool nights, weeds begin to store energy and send it to the crown and roots — and the herbicide moves with it, making it an ideal time for application. Many annuals and perennial weeds will be present on golf courses and turfgrasses during this time, giving you the perfect opportunity to attack a broad spectrum of weeds. Follow these handy steps to create a fall weed control plan:
Identify problem weeds
Don’t waste time and money trying to control the wrong weeds. It’s important to know your offenders ahead of time. Here are some weeds you can target with a fall application:
- Winter annuals, including chickweed, henbit and speedwell. They germinate in late summer and fall, survive through the winter and produce seed in the spring.
- Perennial weeds, such as dandelion, white clover and broadleaf plantain. They live for more than two years and reproduce by seeds, which are spread readily by wind, or attaching to mowers, or foot traffic. It is best to use systemic herbicides as they control the plant — roots and all.
Note weed hot spots
Identify the places where you’ve had difficulties controlling weeds in the past. The growth stage of the plants in these problem spots will indicate when in the fall you should start your broadleaf weed control program.
Select the proper herbicide
If you make your application prior to germination, you’ll want to use a preemergence herbicide, such as Dimension® or Gallery® specialty herbicide. Gallery prevents broadleaf weeds that germinate in the fall, winter and spring. Dimension controls crabgrass and other grassy weeds.
In the North, golf course superintendents (GCS) can make preemergence applications as early as Labor Day. In warmer climates, GCSs can apply as late as October. If you are targeting perennials or weeds that have already germinated, try Defendor® specialty herbicide, a postemergence herbicide that works at preemergence timing. When applied in late fall or early spring, it will eliminate plant growth and prevent bloom.
Determine application timing
This step gives you your application window for the most effective control. Preemergence herbicides should be applied two weeks prior to weed seed germination. If you are using a postemergence herbicide, such as Defendor, you can make applications into late November.
State restrictions on the sale and use of Defendor and Dimension specialty herbicide products apply. Consult the label before purchase or use for full details. Always read and follow label directions. © 2020 Corteva. (08/20) BR CATO0TURF063
Posted In: Featured, Postemergence herbicides, Preemergence herbicides, Weeds 101
