New Jersey Field Office
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Sensitive Joint-vetch (Aeschynomene virginica) [threatened]

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Additional Information

IN BRIEF

Habitat:
Fresh to slightly salty (brackish) tidal marshes

Main Threats:
Habitat loss
Habitat degradation
Sea level rise

Fun Fact:
Sensitive joint-vetch is so-named because its leaves fold slightly when touched.


Map of sensitive joint-vetch distribution in the U.S.
Sensitive joint-vetch distribution in the U.S. (click image for full-size)

Map of sensitive joint-vetch distribution in New Jersey by municipality
Sensitive joint-vetch distribution in New Jersey by municipality
(click image for full-size)

Overview

Sensitive joint-vetch was federally listed as a threatened species in 1992.

An annual member of the pea (legume) family, sensitive joint-vetch can grow up to 6 feet tall. This species has yellow, pea-type flowers growing on clusters (racemes) on short, lateral branches. Germination takes place from late May to early June. Plants flower from July through September, and into October in some years.

Sensitive joint-vetch inhabits the intertidal zone of fresh to slightly salty (brackish) tidal river segments, typically in areas where sediments accumulate and extensive marshes are formed. These tidal marshes are subjected to a cycle of twice-daily flooding that most plants cannot tolerate. Such habitats occur only along stretches of river close enough to the coast to be influenced by the tides, yet far enough upstream that river water is fresh or only slightly brackish. Bare or sparsely vegetated substrate appears to be a habitat requirement for this species, which usually grows on river banks within 6 feet of the low water mark. The plant can also occur on accreting point bars and in sparsely vegetated microhabitats of tidal marsh interiors, such as low swales and areas of muskrat (Ondatra zibethicus) eat-out. This species is typically found in areas where plant diversity is high and annual species are prevalent.

Threats to sensitive joint-vetch include dredging and filling of marshes, dam construction, shoreline stabilization, commercial and residential development, sedimentation, impoundments, water withdrawal projects, invasive plants, introduced insect pests, pollution, recreational activities, agricultural activities, mining, timber harvest, and salt water intrusion due to sea level rise.

Distribution

Species Range: Sensitive joint-vetch is known from Maryland, New Jersey, North Carolina, and Virginia. The historical range for the species extended to Delaware and Pennsylvania.

Distribution in New Jersey: Sensitive joint-vetch is currently known to occur in Cumberland County. The species formerly occurred in Burlington, Camden, Gloucester, Salem, Atlantic, and Cape May Counties.


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Last updated: January 28, 2014
New Jersey Field Office
Northeast Region Ecological Services
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