Total Landscape Care Digital Magazine
Issue link: http://read.dmtmag.com/i/356210
chemical care efficacy for a more complete kill of weeds, but also decreases the chance of damaging turf, which has only just recovered from the stresses of summer. Taking weeds out in the fall can give turf a com- petitive advantage when it emerges in the spring and break the weed cycle. A fall fix In many instances, trying to combat weeds in the summer is not only futile, but it can damage turfgrass, according to Aaron Patton, Ph.D., associ- ate professor and turfgrass extension specialist at Purdue University. "Herbicides are most effective on weeds that are not drought-stressed, and herbicides can be damaging when applied to drought-stressed turf," Patton says. Instead, a fall application minimizes the risks to turf and maximizes efficacy, taking advantage of the weed's lifecycle. "Many herbicides are effective in late fall be- cause plants are more likely to translocate (move downward) herbicides into root and stem tissues as the day lengths shorten and temperatures cool," Patton says. While preparing for winter, weeds are stor- ing energy reserves and will readily suck up herbicides. "When turf and weeds are actively growing in the fall, it's easier for the turf to metabolize herbi- cides. At the same time, these perennial weeds are shifting their requirements to reproductive growth. They are sucking in nutrients, and moisture and can translocate more effectively," Hutto says. Weeds like dandelion, clover, plantain, ground ivy and wild violet are all good candidates for fall weed control. "Wild violet has a pretty nasty rhizome to reproduce vegetatively. It's shifting carbohydrates down into these rhizomes in the fall to be ready to 4 4 To t a l L a n d s c a p e C a r e . c o m A U G U S T 2 014 Wild violet is more susceptible to herbicides in the fall when it is actively growing. PHOTO COURTESY OF WALTER REEVES, THE GEORGIA GARDENER