Pueraria montana var. lobata (Willd.) Maesen & S. Almeida
Pueraria montana var. lobata (Willd.) Maesen & S. AlmeidaKudzu
| Threat Level | Category |
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| Established | Vine |
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Similar Species May be confused with the following native and/or non-native species. Landscape Alternatives lists native horticultural substitutes |
Amphicarpaea bracteata Desmodium rotundifolium |
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Description
Height
Trailing or climbing semi-woody, perennial vines reach 98 feet (30 m) in length.Roots
Kudzu roots typically reach a soil depth of 3-9 feet (1-3 m) and are capable of storing large amounts of carbohydrates. Roots are tuberous, up to 7 inches (17.8 cm) in diameter.Stem
First year vines are pubescent; yellow green stems with dense erect golden hairs and may reach a half inch (1.3 cm) in diameter. Older vines are fibrous, relatively soft, ropelike, light gray, hairless and may reach a diameter of 4 inches (10 cm) with infrequent branching. Mature bark is rough, rigid, and usually dark brown. Stem nodes root when on the ground.Leaves
Foliage is alternate and compound (trifoliate) with leaflets up to 4 inches (10 cm) or more across. Each long-tipped leaflet is entire or 2-3 lobed with hairy margins. Middle leaflet is usually symmetrical, side leaflets may be asymmetrically lobed. Leaf stalks are 6-12 inches (15-30 cm) long with a swollen base. Foliage drops after the first fall frost.Flowers
Kudzu plants do not usually flower until their third year. Pealike flowers are purple with yellow centers, fragrant, about 0.5 inches (1.3 cm) long, and produced in long racemes 2-12 inches (5-30 cm). Blooms July-October.Fruit
Ovoid seeds are contained in flat, 2-3 inches (4-8 cm) long, hairy pods in clusters. Green pods ripen to tan with stiff golden brown hairs and split open on the sides. Matures September-October.Images
Photo: David J. Moorhead, University of Georgia, Bugwood.orgMore images of Pueraria montana var. lobata
Life History
This aggressive vine can grow 60 feet per year forming a continuous blanket of foliage. Twining, trailing and mat-forming, this massive covering often chokes out competing native vegetation that provides food and habitat for native animals. The result is a large-scale alteration of biotic communities. Kudzu is also a problem in forest agriculture and landscaping. It belongs to the Fabaceae, Pea or Bean Family.Kudzu is a deciduous perennial actively growing from early summer (May) until the first frost. Matted dead leaves and bare stems are evident through winter. Sexual reproduction is rare, however seeds have been collected in the Great Smoky Mountains National Park and sprouted in a laboratory dish. Kudzu establishes plants by forming roots at nodes where the vines come in contact with the soil. These roots enlarge to form new crowns. Vines grow rapidly, and increases of 50 feet (15 m) in a single season are not uncommon. Roots can penetrate the soil to depths of 9 feet (3 m). As a legume, it fixes nitrogen in the soil.
Habitat
Kudzu grows well under a wide range of environmental conditions, although greatest growth is achieved where winters are mild (40-60°F), summer temperatures rise above 80°F, and rainfall is abundant (39 inches [101+ cm]). Kudzu can grow in nearly any type of soil (e.g., acid soils, lime soils, lowlands with high water tables, and over heavy subsoil), and where winter soil temperatures remain above -25°F. Large roots allow plants to survive in fairly dry climates and drought conditions. Ideal conditions are moist to well drained and acid to neutral soils (4.5-7.0 pH). New growth may exceed one foot per day. Forest edges or disturbed areas, such as abandoned fields and roadsides, are preferred habitats. Kudzu can persist on the floor of a closed canopy forest; the vines grow up trees toward light and take advantage of any openings.Origin and Distribution
A native of Asia, kudzu was introduced into the United States at the Philadelphia Centennial Exposition in 1876. By 1900, kudzu was available through mail order and sold mainly as an inexpensive livestock forage. The Soil Erosion Service (later renamed the Soil Conservation Service) distributed approximately 85 million seedlings starting in 1933 in an effort to control agricultural erosion. In 1953 the USDA removed kudzu as a cover plant and listed it as a common weed of the South in 1970. It is estimated that kudzu now covers seven million acres in the southeast. Distribution is as far north as Pennsylvania, Illinois, and Connecticut and from eastern Texas to central Oklahoma in the west. The largest infestations are found in Mississippi, Alabama, and Georgia. Other states where invasive: FL, OR, ND, TX, AR, MO, IL, IN, KY, MS, GA, SC, NC, VA, WV, MD, NJ, CT. Federal or state listed as noxious weed, prohibited, invasive or banned: CT, FL, IL, KS, KY, MA, MS, MO, OR, PA, TX, WA, WV.Sources: Information on this plant page derived primarily from the Tennessee Management Manual and James H. Miller's Nonnative Invasive Plants of Southern Forests, USDA Forest Service.
Management Recommendations
Mechanical Control
Grubbing: Using a pulaski or similar digging tool, remove the entire plant, including the taproot. Removed vegetation should be destroyed by burning or bagging. Because many roots exceed 1.8 m, eradication by this method is very difficult and should be considered primarily for small initial incursions.Cutting: Vines and runners are chopped just above the ground level, and the pieces destroyed. Early in the season, cutting is repeated at two-week intervals, to weaken the crown and prevent resumption of photosynthesis. Later in the season, when the stored energy in the taproot has been reduced, the interval between cuttings can be extended. Cutting does not typically kill roots and should only be used to control the spread of kudzu.
Herbicidal Control
Cut Stump Method
Use this method in areas where vines are established within or around non-target plants or where vines have grown into the canopy.Glyphosate: Cut the stem 5 cm (2 in) above ground level. Immediately apply a 25% solution of glyphosate and water to the cross-section of the stem. This procedure is effective at temperatures as low as 40°F, and may require a subsequent foliar application of glyphosate.
Triclopyr: Cut the stem 5 cm (2 in) above ground level. Immediately apply a 25% solution of triclopyr and water to the cross-section of the stem. This procedure remains effective at low temperatures (<60°F) as long as the ground is not frozen. A subsequent foliar application may be necessary to control new seedlings.
Foliar Spray Method
Use this method to control large populations. It may be neces-sary to precede foliar applications with stump treatments to reduce the risk of dam-aging non-target species. After the stems and leaves have been brought under control (i.e., all above ground portions of the plants have been effectively treated) further treatment should follow the Root Crown Method.Glyphosate: Apply a 2% concentration of glyphosate and water plus a 0.5% non-ionic surfactant to thoroughly wet all foliage. Do not apply so heavily that herbicide will drip off leaves. Glyphosate is a non-selective systemic herbicide that may kill non-target partially-sprayed plants. Ambient air temperature should be above 65°F.
Triclopyr: Apply a 2% concentration of triclopyr and water to thoroughly wet all foliage. Do not apply so heavily that herbicide will drip off leaves. A 0.5% concentration of a non-ionic surfactant is recommended in order to penetrate leaf cuticle. Ambient air temperature should be above 65°F.