Take a drive down almost any highway in southwest Alabama this spring, and you’re likely to see lush patches of yellowish-green grass accented by fluffy, white flowers. At first glance, you might think these swaying plumes are just another wildflower beautification project. But ask any farmer or forest owner, and you’ll discover the fancy blooms are merely a clever disguise for the world’s seventh most troublesome weed: cogongrass.Sometimes referred to as Alabama’s next kudzu, cogongrass is a fast-growing, persistent weed that invades farms and forestland, choking out native plants. Once established, the grass is very costly to control and almost impossible to eradicate.Mobile County cattleman Calvin Freeland knows, all too well, what the grass can do to pastureland.”I’ve got about 400 acres of permanent pasture, and about 200 acres of it is cogongrass,” Freeland said. “I tried a couple of years ago to kill it with Roundup™–about two applications a year will control it. But it just creeps back in from fencerows and neighboring farms. I don’t know of anything you can plant that it won’t overtake. It just outgrows everything else.”To make matters worse, Freeland said cogongrass has almost no value as a forage. In fact, the saw-toothed margins of mature cogongrass can actually cut the tongues of cattle.But as aggravating as cogongrass is for cattlemen, it poses an even greater threat for forest owners. Just ask Kyle Redding of Baldwin County.Almost one-third of his timberland is carpeted in cogongrass. Above ground, the waist-high grass dominates the landscape–providing a volatile fuel source for wildfires. The only other plants piercing the forest floor are mature pines, because a dense mat of cogongrass rhizomes prevents any natural regeneration.”It has devalued our land some, but mainly it has limited our options as far as managing timber and developing wildlife habitat,” Redding said. “We will never get long leaf pines established on these sites that have cogongrass. I don’t know what we will do after we harvest the trees. Even if we can control the cogongrass, it will be very expensive.”It’s a story Larry Morris has heard time and time again. As district conservationist for the U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS) in Baldwin County, it’s Morris’ job to advise landowners of forest and wildlife management options.”I came to Baldwin County in 1976, but I probably didn’t notice any real problems with cogongrass until about the mid ’80s. Since then, it’s exploded,” Morris said. “It’s gotten so bad in southern Mobile County and parts of Baldwin County that we can’t control it. What we can do is warn the counties north of here to start controlling it now, before it becomes a problem.”Cogongrass, or Japanese grass, originally entered Alabama through the Port of Mobile in the early 1900s. Experts believe it was used as packing material for Satsuma oranges. A 2000 survey by NRCS and the Alabama Department of Transportation (ALDOT), however, shows the weed has slowly migrated north. Today, more than 30 Alabama counties have at least one infestation of cogongrass including confirmed patches as far north as Winston County and as far east as Auburn.The rapid spread of cogongrass has prompted state and federal officials to take action. Research is currently underway to determine the most cost-effective control methods, and brochures and a video have been produced to educate landowners about this noxious weed.One research project is being conducted by Dr. Jim Miller of the U.S. Forest Service in conjunction with Dr. Mike Patterson of Auburn University and his doctorate student, Wilson Faircloth.”We performed a screening study on two sites to refine the rates of the two herbicides that have been identified throughout the world as being most effective in controlling cogongrass (Accord™ and Arsenal™),” Miller said. “We also are doing a study using chemical and mechanical site preparations to establish loblolly pines on sites heavily infested with cogongrass.”Miller said this research is important because, if cogongrass isn’t controlled and the land reclaimed, much of Alabama’s coastal forestland could be lost forever.
Ironically, while being interviewed for this story Miller received word that his research office has been targeted for closure. That would leave Alabama without a federal forestry research lab and could jeopardize the research he is doing on cogongrass.Meanwhile, he said one of the best things he and other researchers can do is educate landowners about the threat presented by cogongrass.”It presents one of the most dire, long-term threats to our forests because it saps the strength of the forest and stops regeneration,” Miller said. “Fire also is a major concern. Because cogongrass burns so hot, anything under 12 feet would be killed.”
Redding experienced the effects of a cogongrass fire firsthand. He lost 20 percent of his 20-year-old trees to wildfire.Redding said controlled burning only seems to spread cogongrass, because the fire kills competing vegetation.Fortunately, Faircloth said cogongrass can be eliminated by repeatedly tilling the soil. As a result, it has not been a major problem for Alabama row crop farmers. Still, Faircloth and Miller encouraged producers to be on the lookout for cogongrass
and immediately treat any patches with herbicide.Faircloth also is measuring existing patches using a global positioning system, so researchers can track their growth. The Alabama Department of Agriculture and Industries encourages landowners to report any new infestations to Guy Karr in the plant protection division at (334) 240-7100. Karr also warned nursery operators that it is illegal to market “Red Baron” or Japanese bloodgrass–ornamental varieties of cogongrass–in Alabama.For more information about identifying and controlling cogongrass, contact your local Extension System or NRCS office.