Kudzu ia a climbing, semi-woody,
perennial vine in the pea family. Deciduous leaves are alternate and compound,
with three broad leaflets up to 4 inches across. Leaflets may be entire or
deeply 2-3 lobed with hairy margins. Individual flowers, about ½ inch long,
are purple, highly fragrant and borne in long hanging clusters. Flowering
occurs in late summer and is soon followed by production of brown, hairy,
flattened, seed pods, each of which contains three to ten hard seeds.
Kudzu kills or degrades
other plants by smothering them under a solid blanket of leaves, by girdling
woody stems and tree trunks, and by breaking branches or uprooting entire
trees and shrubs through the sheer force of its weight. Once established,
Kudzu plants grow rapidly, extending as much as 60 feet per season at a rate
of about one foot per day. This vigorous vine may extend 32-100 feet in length,
with stems ½-4 inches in diameter. Kudzu roots are fleshy, with massive
tap roots 7 inches or more in diameter, 6 feet or more in length, and weighing
as much as 400 pounds. As many as thirty vines may grow from a single root
IN THE UNITED STATES
Kudzu is common throughout most of the southeastern
U.S. and has been found as far north as Pennsylvania.
HABITAT IN THE UNITED STATES
well under a wide range of conditions and in most soil types. Preferred habitats
are forest edges, abandoned fields, roadsides, and disturbed areas, where
sunlight is abundant. Kudzu grows best where winters are mild, summer temperatures
are above 80 degrees Farenheit, and annual rainfall is 40 inches or more.
BIOLOGY & SPREAD
spread of kudzu in the U.S. is currently limited to vegetative expansion
by runners and rhizomes and by vines that root at the nodes to form new plants.
Kudzu also spreads somewhat through seeds, which are contained in pods, and
which mature in the fall. However, only one or two viable seeds are produced
per cluster of pods and these hard-coated seeds may not germinate for several
Kudzu was introduced into
the U.S. in 1876 at the Philadelphia Centennial Exposition, where it was
promoted as a forage crop and an ornamental plant. From 1935 to the mid-1950s,
farmers in the south were encouraged to plant kudzu to reduce soil erosion,
and Franklin D. Roosevelt's Civilian Conservation Corps planted it widely
for many years. Kudzu was recognized as a pest weed by the U.S. Department
of Agriculture and, in 1953, was removed from its list of permissible cover
For successful long
term control of kudzu, the extensive root system must be destroyed. Any remaining
root crowns can lead to reinfestation of an area. Mechanical methods involve
cutting vines just above ground level and destroying all cut material. Close
mowing every month for two growing seasons or repeated cultivation may be
effective. Cut kudzu can be fed to livestock, burned or enclosed in plastic
bags and sent to a landfill. If conducted in the spring, cutting must be
repeated as regrowth appears to exhaust the plant's stored carbohydrate reserves.
Late season cutting should be followed up with immediate application of a
systemic herbicide (e.g., glyphosate) to cut stems, to encourage transport
of the herbicide into the root system. Repeated applications of several soil-active
herbicides have been used effectively on large infestations in forestry situations.
Efforts are being organized by the U.S. Forest Service to begin a search
for biological control agents for kudzu.
USE PESTICIDES WISELY: ALWAYS READ THE ENTIRE PESTICIDE LABEL CAREFULLY, FOLLOW ALL MIXING AND APPLICATION INSTRUCTIONS AND WEAR ALL RECOMMENDED PERSONAL PROTECTIVE GEAR AND CLOTHING. CONTACT YOUR STATE DEPARTMENT OF AGRICULTURE FOR ANY ADDITIONAL PESTICIDE USE REQUIREMENTS, RESTRICTIONS OR RECOMMENDATIONS.
NOTICE: MENTION OF PESTICIDE PRODUCTS ON THIS WEB SITE DOES NOT CONSTITUTE ENDORSEMENT OF ANY MATERIAL.
For more information on kudzu management,
- Robert J. Richardson, Aquatic and Noncropland Weed Management, Crop Science Department, Box 7620, North Carolina State University, Raleigh, NC 27695-7620, (919) 515-5653, Rob_Richardson at ncsu.edu
- James H. Miller, USDA Forest Service, DeVall
Drive, Auburn University, AL 36849 Miller at forestry.auburn.edu
SUGGESTED ALTERNATIVE PLANTS
such as trumpet creeper (Campsis radicans), pipevine (Aristolochia
macrophylla), passionflower (Passiflora lutea), trumpet honeysuckle
(Lonicera sempervirens), and native bittersweet (Celastrus scandens)
have attractive flowers and fruits, provide food for wildlife and make excellent
substitutes for kudzu. These plants should be used in landscaping and for land
restoration where they are known to occur as natives.
Carole Bergmann, Montgomery County Department
of Park and Planning, Silver Spring, MD
Jil M. Swearingen, National Park Service,
Jil M. Swearingen, National Park Service,
McKnight, B.N., ed. 1993. Biological Pollution.
Indiana Academy of Sciences, Indianapolis, IN. 261 pp.
Miller, J.H. and B. Edwards. 1982. Kudzu: Where
did it come from? And how can we stop it? Southern Journal of Applied Forestry.
Randall, J.M. and J. Marinelli. 1996. Invasive
Plants:Weeds of the Global Garden. Brooklyn Botanic Garden Club, Inc. Handbook
No. 149. 111 pp.
Swearingen, J. 2009. WeedUS Database of Plants Invading Natural Areas in the United States: Kudzu (Pueraria montana var. lobata). http://www.invasive.org/weedus/subject.html?sub=2425.
USDA, NRCS. 2009. The PLANTS Database (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.
Virginia Native Plant Society. 1995. Invasive
alien plant species of Virginia: kudzu [Pueraria lobata (Willd.) Ohwi].
Virginia Department of Conservation and Recreation, Richmond, Virginia.
Plant Conservation Alliance, Alien Plant Working Group.