 |
Photo by Jill Swearingen, USDA National Park Service |
Kudzu
If you can't beat it, eat it
It's mean, green and downright nasty — at least to most farmers, who consider kudzu one of the dirtiest words in the English language. The creeping vine from Japan can swallow a barn in a single summer and turn woods into abstract art. And now that it covers more than 7 million acres of the Deep South, a lot of folks want it dead.
Creepy, crawly kudzu is the plant world's equivalent of roaches and fire ants, which also are nearly impossible to eradicate.
Kudzu first appeared in the South as a popular porch vine, adored for its shade and fragrant blooms. During the Depression, it helped stop soil erosion after decades of shoddy farm practices on cotton and tobacco plantations depleted the soil and turned it into red clay wasteland. The fast-growing vine with its deep taproots kept the soil in place and re-nourished it. Like its legume cousins — peanuts, soybeans, alfalfa and clover — kudzu's roots contain bacteria that fix nitrogen into the soil, making the plant a natural fertilizer. Farmers initially anointed kudzu the ''Savior of the South.''
By the 1960s, the miracle vine fell from grace. It had become an uncontrollable nuisance that strangled Southern fields and forests. Unchecked, it did not act like it did at home in the Orient, where the combination of cold winters, natural enemies and extensive cultivation always kept it under control. Here, once established, kudzu took over completely.
The kudzu vine has large leaves on long, winding stems that grow 50 to 100 feet long. They grasp, cover and climb on, over and around anything within reach. The leaves form a lightproof canopy, smothering and eventually eliminating competitors. In the late summer, clusters of fragrant flowers appear, followed by seeded flat pods typical of legumes. The enormous taproots penetrate deep into the ground, enabling kudzu to withstand cold Northern climates and survive underground.
By the time these features became too obvious to ignore, kudzu blanketed a sizable section of the country and interest turned from conservation to eradication. At one point in the last half century, Alabama considered kudzu contraband and made it illegal to plant the vine or to own seeds and seedlings. Undeterred since then, kudzu has slithered and slinked northward, showing up in unlikely places like New York City, where some vacant lots are covered in a wicked web of green foliage more reminiscent of rural Southlands than the concrete jungle.
Battling kudzu
Some foresters say killing kudzu takes at least 10 years of aggressive chemical application, but even then total eradication isn't guaranteed. People who go this route, however, should use broad-spectrum herbicides that contain glyphosate, the active ingredient found in common commercial weed killers like Round Up, which works best when sprayed in early fall. That time of year, the plant is drawing nutrients from the leaves and stems to the roots in preparation for the winter dormant period. Other popular chemicals include Veteran 720, Rodeo, Accord and Tordon.
Because fighting kudzu is labor intensive and expensive, landowners and foresters — even some cities and towns — are turning to goats, which attack the vine with such ferocity they eventually kill it. Another benefit of that method is money, not just saving it but making it, too, when the goats produce milk or are sold for meat. Cows, sheep, horses and deer also are drawn to kudzu, which is high in starch and protein.
Humans eat it, too. Kudzu leaves are tasty salad greens, and its blossoms make a fragrant jelly. Research suggests kudzu even curbs alcohol cravings and eases hangover pains. Crafters fashion baskets and ropes from the vines.
Another possible use for kudzu is bio-fuel. Kudzu roots are similar to corn, in that the carbohydrate can be converted to ethanol. Rowan Sage of the University of Toronto and colleagues at the U.S. Department of Agriculture believe kudzu could be part of the solution to fuel concerns.
"Kudzu is just a large amount of carbohydrate sitting below ground waiting for someone to dig it up," Sage said. The root is 68 percent carbohydrate and just one acre can produce about the same amount of ethanol as an acre of corn.
"It's not going to solve anybody's energy crisis, but it would be a useful supplement," Sage said.
Bob Tanner of Vanderbilt University had the idea of using kudzu as a bio-fuel in the 1970s. Now he knows that it has many different uses.
"My suggestion is be creative," Tanner said. "Don't cuss at it. Use it." — Chasiti Kirkland