HUEBNER, CYNTHIA D. USDA Forest Service, Northeastern Research Station, 180 Canfield St., Morgantown, WV 26505-3180. - Distribution of invasive plant species in eastern oak-hickory forests of West Virginia.
Are invasive plant species a threat to oak-hickory forests of West
Virginia? Invasive plant species are often characterized by early
successional traits, including small seeds that are wind and animal
dispersed, vegetative growth, and shade-intolerance, all of which
enable the plants to take advantage of disturbed areas and spread
rapidly. One may conclude that these traits do not lend themselves to
easy invasion of a forest and the apparent low impact of invasive
plant species on forests, compared to riparian and rangeland sites,
may support this. However, oak-hickory forests are unique because
their canopies are relatively open compared to other hardwood forests,
and the native species respond well to openings caused by various
disturbance types. In fact, management regimes to maintain
oak-dominated forests include clear-cutting and fire, both of which
may promote exotic invasion. Moreover, eastern forests may be
described as patches within an urban and agricultural matrix; i.e.,
the sink of invasion is embedded in its source. While there are over
180 potential oak-hickory forest invaders, we found the following
species of most concern: Alliaria petiolata,
Microstegium vimineum, Lonicera japonica,
Celastrus orbiculatus, Rosa multiflora,
L. maackii, L. tatarica, L.
morrowii, and Ailanthus altissima. I compared
each species’ traits (physical, reproductive, and physiological),
competitive ability, control measures, and known impacts on succession
and ecosystem processes (based on the literature). I then related the
distribution of these species (using herbarium records) to patterns of
forest fragmentation and land use (using digital images). I used this
information to predict future impacts of invasive plant species on
oak-hickory forests.
Key words: invasive plants, oak-hickory forests, West Virginia