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Exotic Wisterias
Wisteria
floribunda, Wisteria
sinensis
Identification
Chinese and Japanese wisterias are two species of wisteria in the United States that
have escaped ornamental plantings and are now considered invasive in
natural areas. Wisterias are climbing woody vines that have
deciduous leaves which are pinnately compound and arranged
alternately on the stem. Wisteria can become quite large, growing up
to fifteen inches in diameter. They are also very long lived; some
specimens commonly live over fifty years. The flowers appear in
spring and are quite showy, being purple in color and resembling
bunches of grapes. The fruit is a hairy seed pod resembling a pea
that is seven to nine inches in length.
One species of
wisteria is native to the United States, Wisteria frutescens,
is very similar, but the fruits are hairless, and the plant is not
as aggressive as the two previously mentioned exotic species.
Origin
China and Japan
Habitat
Exotic wisterias
prefer full sun, but will persist in shade long enough to climb
nearby trees and get to sun. They can even reproduce in shade.
Wisteria sometimes creates its own disturbance by breaking down
trees and exposing itself to sunlight. It commonly invades areas
such as roadsides, forest edges, and rights-of-way. It is very
adaptable to all but the most extreme of soil and moisture
conditions.
Ecological Threat
Exotic wisteria is
a very aggressive spreading and climbing vine that destroys shrubs
and trees by shading them out, choking off water and nutrients
(girdling), and by simply breaking them down. It can very quickly
take over an area and turn it in to an impassable thicket where all
native plants have been eradicated.
Recommended Native Alternatives
-
American
wisteria (Wisteria frutescens)
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Virginia
creeper (Parthenocissus quinquefolia)
-
Crossvine (Bignonia
capreolata)
These pages are designed to give the
layperson a general overview of non-native invasive plants commonly
found in the upper Hiwassee River watershed. For more comprehensive
and technical information about a particular species, visit one of
the web sites from our
Links
page. |
