| SOURCE: The following information on this
species is taken from the Delaware River Invasive Plant Partnership, Invasive
Plant Fact Sheets at http://www.paflora.org/DRIPP.html.
Modifications include additional pictures (from www.invasives.org)
and resource information. Check the website links for future updates. The last
update for this fact sheet is June 2003.
|
DESCRIPTION:
Wisteria is a long-lived, vigorous, deciduous, woody, climbing and twining vine.
Height -
Wisteria vines may climb to a height of 60-70 feet or more if suitable support
is available.
Stem
- Wisteria stems twine around any solid support, including trees, fences,
buildings, and even each other. They are smooth and gray in color and can
attain diameters of up to 5 inches or more.
Leaves
- The leaves of wisteria are pinnately compound with 7-19 leaflets; they are
arranged alternately on the stem.
Flowers
- Wisteria flowers are showy, violet-blue in color, and occur in 6-18
inch-long, drooping clusters that appear before the leaves have expanded.
Fruit and seed
- The fruits of Chinese and Japanese wisteria are fuzzy, flattened pods about
4-5 inc hes long containing 4 -6 seeds.
|
Photos or Chinese wisteria: Upper left/lower right: Ted Bodner, Southern Weed
Science Society; Upper left/middle: James H. Miller, USDA Forest Service; Lower
left: J. Scott Peterson, USDA NRCS.
Source for all is www.forestryimages.org.
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DISTRIBUTION
AND HABITAT:
Wisteria is a popular ornamental landscape plant, esteemed for its showy
blooms. Although there is a native North American species of wisteria, Chinese
and Japanese wisteria are preferred by the horticultural industry because the
inflorescences are larger and the plants more vigorous. Besides its smaller
inflorescence (3-4 inches long), the native American wisteria may be
distinguished by its smooth seed pod. The native species [Wisteria frutescens
(L.) Poir.] grows naturally from Virginia to Florida; occurrences of it in
Pennsylvania appear to be the result of plantings.
EFFECTS OF
INVASION:
Naturalized populations of Chinese and Japanese wisteria seem to result from
abandoned plantings at former home sites or old nurseries. The vines can spread
over large areas of forest, twining around trees and eventually competing for
space in the canopy. A dense, nearly impenetrable thicket has resulted in some
areas; normal forest succession can be inhibited.
|
Photo: Randy Cyr,
GREENTREE Technologies,
www.forestryimages.org
|
Photo: James R. Allison,
Georgia Department of Natural Resources,
www.forestryimages.org.
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REPRODUCTION
AND METHODS OF DISPERSAL: Most infestations of non-native wisteria appear to be the result
of the persistence and vegetative spread of former plantings, although seed
propagation is also possible.
NATIVE ALTERNATIVES
FOR LANDSCAPE USE:
The native American wisteria (Wisteria frutescens) is a good alternative
to non-native wisterias, especially in areas adjacent to forests.
AUTHORS:
Ann F. Rhoads and Timothy A. Block, Morris Arboretum, University of
Pennsylvania
For more information
on Chinese and Japanese wisteria, please contact:
Mid-Atlantic Exotic Pest Plant Council, Inc., http://www.ma-eppc.org
National Invasive Species Information Center,
http://www.invasivespeciesinfo.gov
Plant Conservation Alliance, Alien Plant Working Group, Weeds Gone Wild Fact
Sheets, http://www.nps.gov/plants/alien/factmain.htm
Plant Invaders of Mid-Atlantic Natural Areas,
http://www.nps.gov/plants/alien/pubs/midatlantic/wist.htm
Southeast Exotic Pest Plant Council; Invasive Plant Manual,
http://www.se-eppc.org/manual/
The Bugwood Network, MA-EPPC Plant List,
http://www.invasive.org/maweeds.cfm
The Nature Conservancy Invasive Species Initiative,
http://tncweeds.ucdavis.edu/esadocs.html
USDA Forest Service, Nonnative Invasive Plants of Southern Forests,
http://www.invasive.org/eastern/srs/
USDA Forest Service, Northeastern Area, Invasive Plants: Weeds of the Week,
http://www.na.fs.fed.us/fhp/invasive_plants/weeds/
USDA - NRCS PLANTS Database, http://plants.usda.gov/
REFERENCES:
Rhoads, A. F. and T. A. Block. 2000. The Plants of Pennsylvania, An Illustrated
Manual. University of Pennsylvania Press, Philadelphia.
Management and
Control Information
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