Q: Don't you have to dig up kudzu roots to kill the plant and keep it from coming back?
A: No. It is only necessary to kill or remove the node or crown that sits on top of the roots. Nodes and crowns are normally just above or below ground level. Kudzu roots do not sprout.
Q: I read that kudzu has rhizomes, underground stems. Isn't that how kudzu spreads?
A: No. Kudzu only has vines that grow above ground. Vines are frequently covered up by leaf litter and other debris, and are mistaken for underground rhizomes. This is especially true of old vines, which when underground can still "sprout" vines that emerge above ground. It is more accurate to refer to kudzu vines as stolons, horizontal stems (vines) that form from nodes on other stems. Rhizomes and stolons are often confused terms. A detailed discussion of their differences, which are not obvious, is left to experts.
Q: Kudzu spreads by seed, yes?
A: Perhaps, but not very well. Studies show that only about 20% of kudzu seeds are viable and capable of germinating under natural conditions. But these viable seeds do not germinate easily. Given that vines grow up to 90 feet per year, and vine sprouting nodes grow every 8 inches or so along new vines, it is easy to see that kudzu spreads mostly by vine growth. Coalition volunteers very rarely pull up a kudzu plant that clearly developed from a seed. Most suspected cases of seedlings are cases of mistaking other plants for kudzu. For example, small native pea plants look very much like kudzu, which is not surprising because both plants are legumes.
Q: What's wrong with using herbicides to control kudzu?
A: Nothing, as long as they are used properly. However, annual treatments over several years are generally necessary to kill an isolated stand of kudzu. In cases where manual removal of the crowns is practical, a quicker kill is possible, although no known method kills kudzu with 100% effectiveness with one treatment. Also, there are some situations where it is inadvisable to apply chemicals due to nearby bodies of water because of potential damage to wildlife or contamination of water supplies. Note too that most chemicals effective against kudzu require a license and special safety precautions.
Q: Isn't it unreasonable to think that kudzu can be controlled purely by nonchemical methods?
A: It appeared "unreasonable" to think that a kudzu plant could be killed without treating its roots, but the Coalition has demonstrated that is the case. So what appears "unreasonable" now can change. Perhaps the large tracts of kudzu in the Southeast are vulnerable to some nonchemical method not yet devised.
Q: Does kudzu come from Japan?
A: Kudzu is native to China, but is now found throughout Asia and other parts of the world. Kudzu was first brought to the United States by Japan as part of an exhibition.
Q: Kudzu grows remarkably well in the Southeast. Is that because it fixes its own nitrogen?
A: Kudzu is a legume, and scientific literature states that kudzu can be inoculated by nitrogen fixing bacteria. However, we have not observed root nodules on kudzu roots that indicate inoculation. The vigorous growth of kudzu in the Southeast is more likely due to that fact that the type of photosynthesis used by kudzu is compatible with the intense sunlight and high temperatures of the Southeast. Possibly important too is that natural pests of kudzu found in Asia do not live in the United States.