Theres still time to treat winter annuals such as henbit, pictured above, and other susceptible species.
Don’t quit yet. Fall can be the best time to spray several weed and brush species, say Range & Pasture experts with Corteva Agriscience.
Blackberry, sericea lespedeza, tropical soda apple, thistles and biennial and winter annual broadleaf weeds are all susceptible to foliar applications in the fall.
With fall spraying, you set up your pastures for a clean, fast start next spring. Soil nutrients and moisture all go to grass when the growing season begins. “Especially in the case of thistles and winter annuals, it’s like they were never there,” says Scott Flynn, Ph.D. Flynn is a field scientist for Corteva Agriscience.
Another advantage of fall application: time availability. Many producers have more time in the fall, and commercial applicators may be less busy.
See the nearby table for rates, and observe these tips on timing.
Blackberry plants are most susceptible to herbicides after the fruit drops in late spring and again in the fall prior to frost. Spray blackberry only under favorable growing conditions when it has healthy foliage. Don’t spray after frost when leaves are damaged.
Maturity of the foliage makes a difference, too. “If blackberry has been mowed, make sure it has at least a full summer’s growth before you spray,” Flynn says.
It’s critical to thoroughly cover foliage with spray solution. If your sprayer can’t get over the blackberry this year, mow now and come back to spray next fall, he says.
For blackberry, Flynn recommends broadcast applications of a tank mix of DuraCor® herbicide with PastureGard® HL herbicide. A follow-up application a year later may be needed. Use the same mix.
The best time to spray buckhorn plantain is when it’s in full rosette form from fall to early spring (generally late October to early April) under favorable growing conditions. The full rosette form is important. It’s also important to have daytime temperatures of at least 60 F for a three-day period (day of spraying, two days after). Buckhorn plantain rosettes are low-growing so the surrounding thatch should not be so tall that it prevents the spray from reaching the ground. Use enough water (total volume) to penetrate any canopy and cover the rosette.
Sericea lespedeza is susceptible to fall spraying as long as the plant isn’t drought-stressed. Blooming is the indicator. Sericea populations will show few blooms when the plants are stressed. If blooms are plentiful, the experts say it’s OK to spray. PastureGard HL herbicide is your tool of choice here.
Tropical soda apple can germinate year-round, but, with sufficiently warm weather, you may have the most germination in the fall and early winter. That’s when tropical soda apple can take advantage of less grass competition. Spray when plants are actively growing — when the high temperature is at least 55 F and will be for a few days. Don’t spray too soon after a frost. If the plants have been subjected to frost, wait for new growth to appear and good growing conditions before you spray.
DuraCor at either 16 or 20 ounces per acre will control tropical soda apple and provide soil residual activity in the soil to control later germinations. The higher suggested rate will extend that residual activity. Apply in at least 20 gallons of water per acre to ensure coverage.
As a rule of thumb for thistles and winter annuals, spray on a day when the high temperature is at least 55 F and will be for a couple of days. Spray before the first hard frost. After that, the plants may be less responsive.
A fall treatment typically gives your grass a head start in the spring, but don’t expect the soil residual activity to last into next summer. For horsenettle or other weeds that emerge in the summer, plan to spray again.
Connect with Range & Pasture:
® Trademarks of Corteva Agriscience and its affiliated companies. Under normal field conditions, DuraCor® is nonvolatile. DuraCor has no grazing or haying restrictions for any class of livestock, including lactating dairy cows, horses (including lactating mares) and meat animals prior to slaughter. Label precautions apply to forage treated with DuraCor and to manure and urine from animals that have consumed treated forage. DuraCor is not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Always read and follow label directions.
Learn about seasonal opportunities, rancher success stories, and management strategies for pastures and rangeland.
