For many, the vivid depictions of kudzu had simply become the defining imagery of the landscape, just as palms might represent Florida or cactus Arizona. But for others, kudzu was a vine with a story to tell, symbolic of a strange hopelessness that had crept across the landscape, a lush and intemperate tangle the South would never escape.
Confronted by these bleak images, some Southerners began to wear their kudzu proudly, evidence of their invincible spirit. Kudzu: A Southern Musical toured the country. In news media and scientific accounts and on some government websites, kudzu is typically said to cover seven million to nine million acres across the United States.
In the latest careful sampling, the U. Forest Service reports that kudzu occupies, to some degree, about , acres of forestland, an area about the size of a small county and about one-sixth the size of Atlanta. By way of comparison, the same report estimates that Asian privet had invaded some 3. Invasive roses had covered more than three times as much forestland as kudzu.
And though many sources continue to repeat the unsupported claim that kudzu is spreading at the rate of , acres a year—an area larger than most major American cities—the Forest Service expects an increase of no more than 2, acres a year. Even existing stands of kudzu now exude the odor of their own demise, an acrid sweetness reminiscent of grape bubble gum and stink bug.
A study of one site showed a one-third reduction in kudzu biomass in less than two years. The widely cited nine-million-acre number appears to have been plucked from a small garden club publication, not exactly the kind of source you expect a federal agency or academic journal to rely on. Yet the popular myth won a modicum of scientific respectability.
Today, it frequently appears on popular top-ten lists of invasive species. The official hype has also led to various other questionable claims—that kudzu could be a valuable source of biofuel and that it has contributed substantially to ozone pollution. As trees grew in the cleared lands near roadsides, kudzu rose with them. It appeared not to stop because there were no grazers to eat it back. Considerable time and money are also spent at national and state parks as well as other federal and state lands to control kudzu, especially when threatening national monuments, historical sites, or other sensitive areas.
Kudzu is a nitrogen-fixing species, and dense infestations have the potential to significantly affect nitrogen cycling. Alteration of the nitrogen cycle can affect soil fertility, water quality, and biodiversity. Kudzu also has the potential to affect air quality, as it is an intermediate to high emitter of isoprene. Isoprene is a photochemically reactive hydrocarbon that can contribute to ozone and smog production. All plants produce isoprene, but not all produce as much as kudzu. Depending on what species a kudzu infestation has replaced, isoprene levels may be higher in the vicinity.
This is especially the case during hot and dry periods of the year. Kudzu also serves as a host for significant agricultural diseases and insect pests including Asian soybean rust and the kudzu bug Megacopta cribraria. Kudzu bugs are of special importance as they were first detected in , but within a few years, these strong fliers have spread throughout much of the southeast. A true stink bug, kudzu bugs suck sap from kudzu and many other plants, including soybeans.
On average, kudzu bugs have reduced soybean yields by 18 percent, but losses as high as 47 percent have been reported. Kudzu bugs are also an urban pest as they congregate around homes and other buildings and emit a foul-smelling chemical. Kudzu bugs do damage kudzu and appear to reduce its vigor and climbing ability. However, to date, their impact has not yet been enough to control kudzu. Figure 6. During the s, kudzu was promoted as an inexpensive forage and for erosion control.
The history of kudzu in the United States is a compelling story, but also a cautionary tale of how good plants can go bad. Although scientists now use risk assessment tools to evaluate the potential for invasiveness in new plant introductions, it is still an imperfect process, and there is much yet to be learned.
Without a doubt, kudzu is here to stay. Although landowners can get effective kudzu control, eradication from the United States is not currently feasible. It is clear that kudzu is continuing to expand its range in the United States and has yet to reach its ecological potential.
Future research will help clarify the full impacts of kudzu and what can be done about it. Invasive Species. Description Kudzu Pueraria montana var. History Approximately 15 species of kudzu Pueraria spp. Figure 2. Young kudzu vines are covered with erect golden hairs and climb by twining. Figure 3. Kudzu roots grow down from a root crown located on the soil surface.
Impacts Although kudzu is widely assumed to have significant negative ecological impacts, the influence of kudzu on biodiversity and ecological processes are surprisingly poorly studied. Figure 4.
Kudzu flowers are typically produced on plants that are climbing or draped over vegetation or other objects. Note the kudzu bugs at the base of the flower. Figure 5. Kudzu fruits are flattened seed pod legumes. Did you find this helpful? It was helpful. It wasn't helpful. This website would like to use cookies to collect information to improve your browsing experience.
Please review our Privacy Statement for more information. Do you accept? Accept Deny Privacy policy. Revoke cookies. From the s through the s, the Soil Conservation Service promoted it as a great tool for soil erosion control and was planted in abundance throughout the south.
Little did we know that kudzu is quite a killer, overtaking and growing over anything in its path. Kudzu grows out of control quickly, spreading through runners stems that root at the tip when in contact with moist soil , rhizomes and by vines that root at the nodes to form new plants.
Once established, kudzu grows at a rate of one foot per day with mature vines as long as feet. An invasive plant as fast-growing as kudzu outcompetes everything from native grasses to fully mature trees by shading them from the sunlight they need to photosynthesize.
This loss of native plants harms other plants, insects and animals that adapted alongside them, leading to cascading effects throughout an ecosystem. Over time, these effects of habitat loss can lead to species extinctions and a loss of overall biodiversity. Climate change puts a lot of stress on native species. Invasive species like kudzu are often more flexible and adaptable to change than many native plants and can outcompete them early in the growing season.
Kudzu thrives in areas with mild winters and hot summers. Climate change may be making it easier for creeping vine to spread, as winters in many areas of the U. Climate change also can lead to more regional drought, an opportunity for this versatile killer.
Kudzu is able to weather dry periods with its deep root systems and then take over where native plants could not survive. Learn more about climate change here. It depends how large the patch is. Newer, smaller patches can be controlled with persistent weeding.
For larger growths, the vines should be cut near the ground and then carefully treated with one of a variety of herbicides.
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