Where is Sensitive Joint-vetch (Aeschynomene virginica)
located in the wild?
Aeschynomene virginica is native to freshwater tidal marshes of the mid-Atlantic states (USFWS 1992). These marshes exhibit twice-daily tides, but occur far enough upstream that they are nearly fresh or barely brackish in water chemistry. Salinity of one site in New Jersey ranges from 0.7 to 0.8 ppt with an average pH of 4.4. (NatureServe 2001). Only a small group of plants can tolerate this tidal inundation; thus, freshwater tidal marshes are home to many specialized and rare species. Aeschynomene virginica grows low in the intertidal zone where soils may be mucky, sandy, or gravelly (Department of Conservation and Recreation 1997). Aeschynomene virginica may perform best in areas of the marsh where competition with other plants is reduced -- for example, newly accreting shores or openings created by wrack deposition or muskrat activity (Department of Conservation and Recreation 1997). In North Carolina, A. virginica has been found in a few road-side ditches and wet corn fields, but these are not considered stable populations (Leonard 1985, USFWS 1992). Biological inventories of available freshwater tidal marsh habitat in North Carolina did not turn up additional populations, so the outlook for the taxon in that state is uncertain. Plant species commonly associated with A. virginica include: Zizania aquatica, Peltandra virginica, Pontederia cordata, Bidens laevis, Polygonum arifolium, P. sagittatum, and Leersia oryzoides, and, in southern areas, another similar legume, Chamaecrista fasciculata var. macrosperma (Department of Conservation and Recreation 1997, NatureServe 2001).
Known from 24 documented populations in New Jersey, Maryland, North Carolina, and Virginia. The species is most abundant in Virginia, with 20 populations occurring there along six rivers. An additio
States & Provinces:
Sensitive Joint-vetch can be found in Delaware, Maryland, New Jersey, North Carolina, Pennsylvania, Virginia