Jesup's Milkvetch / Center For Plant Conservation
Search / Plant Profile / Astragalus robbinsii var. jesupii
Plant Profile

Jesup's Milkvetch (Astragalus robbinsii var. jesupii)

This 20-60 cm tall legume has small (1 cm across) violet flowers and compound leaves w/ 9-17 leaflets. Photo Credit: Arieh Tal
  • Global Rank: T1 - Critically Imperiled
  • Legal Status: Federally Endangered
  • Family: Fabaceae
  • State: NH, VT
  • Nature Serve ID: 129211
  • Lifeform: Forb/herb
  • Date Inducted in National Collection: 03/05/1993
Description:

Astragalus robbinsii var. jesupii is an extremely rare member of the bean family, found only at three sites along a 15-mile stretch of the middle Connecticut River in New Hampshire and Vermont. This plant is found only in areas that receive periodic ice-scouring that clears competing vegetation from riverbanks. Although it has fairly specialized habitat requirements, it is somewhat surprising that the species is so rare, as it occupies very little of the potential habitat available to it. Its tenuous existence is threatened by a number of activities, like damming, that alter the hydrological and disturbance regime of a waterway; trampling by recreational boaters; and historical over-collecting that may have significantly reduced its numbers. Research and Management Summary: Fairly limited research has been conducted on this taxon, but populations are regularly monitored, and the New England Wild Flower Society has undertaken a reintroduction project. Plant Description: Astragalus robbinsii var. jesupii grows 20 to 60 cm (0.65 - 2.0 ft) tall from a thick rhizome or taproot. Like many legumes, it has compound leaves, with 9 to 17 sparsely hairy leaflets each about 1 cm (0.4 in) long. Pale purple to violet flowers 1 cm across are produced in late May to mid-June, and have a papery texture. In late June, plants produce beaked legumes ("pea pods") approximately 2 cm (0.8 in) long, which are covered with small black hairs.

Where is Jesup's Milkvetch (Astragalus robbinsii var. jesupii) located in the wild?

Habitat:

Astragalus robbinsii var. jesupii is reported only from rocky shores of the Connecticut River composed of phyllite or chlorite schist. Like other members of the Astragalus robbinsii complex, this variety is associated with rock that is rich in calcium and magnesium (U. S. Fish and Wildlife Service 1989, NatureServe 2001). The plants occur on moderately steep bedrock slopes that face east or southwest, in crevices and shelves where some litter and sediment has been deposited. The river shores where this plant can be found are periodically scoured by ice breaking up and floating down the Connecticut River in spring; thus, plants are sparse and few species that cannot tolerate such disturbance are present.Other associated species recorded in this boreal river shore outcrop community include: Senecio pauperculus (ragwort), Toxicodendron radicans (poison ivy), Poa compressa, Chrysanthemum leucanthemum, Hypericum perforatum, Solidago canadensis, Campanula rotundifolia, Erigeron pulchellus, Galium mollugo, Alnus rugosa, Ulmus americana, and Salix spp., as well as several rare or specialized calcium-loving plant species such as Allium schoenoprasum var. sibiricum, Carex garberi, Hypericum pyramidatum, and Tofieldia glutinosa.

Distribution:

Astragalus robbinsii var. jesupii is known only from Vermont and New Hampshire (Brackley and Thompson 1985, NatureServe 2001).

States & Provinces:

Jesup's Milkvetch can be found in New Hampshire, Vermont

Which CPC Partners conserve Jesup's Milkvetch (Astragalus robbinsii var. jesupii)?

  • Native Plant Trust

    Sponsored
    Sponsors Add

    Silver Sponsor

    Ellis L. Phillips Foundation

    Andrew W. Mellon Foundation

    Conservation Actions
    Assigned 06/09/17
    • CPC's Plant Sponsorship Program provides long term stewardship of rare plants in our National Collection. We are so grateful for all our donors who have made the Plant Sponsorship Program so successful. We are in the process of acknowledging all our wonderful plant sponsorship donors on our website. This is a work in progress and will be updated regularly.

    Conservation Actions

    • 08/27/2020
      • Orthodox Seed Banking

    Germination and storage techniques are relatively well-known for Astragalus robbinsii var. jesupii. Seed in storage can remain viable for more than six years, but the presence of a seed bank at the New Hampshire and Vermont sites has not been confirmed.

    • 08/27/2020
      • Propagation Research

    Phil Nothnagle (Consulting Botanist, Vermont) has also worked on propagation of the species (New Hampshire TNC 2001).

    • 08/27/2020
      • Propagation Research

    The New England Wild Flower Society (NEWFS) in Framingham, Massachusetts has determined reliable methods for germinating plants. Plants at NEWFS have germinated readily and survive to flowering. However, long-term survival after flowering has been problematic. Plants are growing in the NEWFS garden. The best ex situ germination occurs when seeds have been lightly scarified with sandpaper, possibly mimicking the spring scouring experienced by seeds in the wild (W. E. Brumback, New England Wild Flower Society, personal communication).

    • 08/27/2020
      • Demographic Research

    Three populations are recorded: two in New Hampshire and one in Vermont. Plant numbers fluctuate dramatically from year to year; total observed populations have hovered between 200 and 900 plants (U. S. Fish and Wildlife Service 1989, The Nature Conservancy [TNC], New Hampshire Chapter 2001). Frankie Brackley-Tolman (Keene State College, New Hampshire) and Debra Dunlop (New England College, New Hampshire) have conducted ecological field research on Astragalus robbinsii var. jesupii.

    • 08/27/2020
      • Reintroduction

    Reintroduction of Astragalus robbinsii var. jesupii has been undertaken by the New England Wild Flower Society. After several years of battling floods and drought, and developing techniques for introducing both plants and seed, this reintroduction program is gaining ground (New Hampshire TNC 2001; Brumback, personal communication)

    Nature Serve Biotics
    • 05/02/2017

    Limited to three extant sites along a 25-km stretch of the Connecticut River. The total number of individuals has been 2000 or less, sometimes much less, in recent years; populations at all known sites exhibit year-to-year fluctuation. The plants are confined to a narrow ecotone with a specific disturbance regime: an annually ice-scoured and flooded strip between barren rock and the forested upper portions of the river bank. Threats include invasive plant species, potential hydropower projects (which would disrupt the specific disturbance regime that this plant requires), drought, deer herbivory, and trampling by recreational users.

    Elizabeth J. Farnsworth
    • 01/01/2010

    As articulated by the U. S. Fish and Wildlife Service (1989) and NatureServe (2001): Altered hydrology (due to damming, engineering [Ferrick et al. 1988], naturally changing river courses, or climatic change) that results in changing ice scour patter

    Elizabeth J. Farnsworth
    • 01/01/2010

    Three populations are recorded: two in New Hampshire and one in Vermont. Plant numbers fluctuate dramatically from year to year; total observed populations have hovered between 200 and 900 plants (U. S. Fish and Wildlife Service 1989, The Nature Conservancy [TNC], New Hampshire Chapter 2001).

    Elizabeth J. Farnsworth
    • 01/01/2010

    Frankie Brackley-Tolman (Keene State College, New Hampshire) and Debra Dunlop (New England College, New Hampshire) have conducted ecological field research on Astragalus robbinsii var. jesupii. The New England Wild Flower Society (NEWFS) in Framingham, Massachusetts has determined reliable methods for germinating plants. Plants at NEWFS have germinated readily and survive to flowering. However, long-term survival after flowering has been problematic. Plants are growing in the NEWFS garden. Phil Nothnagle (Consulting Botanist, Vermont) has also worked on propagation of the species (New Hampshire TNC 2001).

    Elizabeth J. Farnsworth
    • 01/01/2010

    The Vermont and New Hampshire Natural Heritage Programs, along with volunteer task forces of the New England Plant Conservation Program (NEWFS, Framingham, Massachusetts) and other conservation partners, regularly monitor populations of Astragalus robbinsii var. jesupii Reintroduction of Astragalus robbinsii var. jesupii has been undertaken by the New England Wild Flower Society. After several years of battling floods and drought, and developing techniques for introducing both plants and seed, this reintroduction program is gaining ground (New Hampshire TNC 2001; Brumback, personal communication). Natural Heritage Programs and The Nature Conservancy of both states are working to protect current and potential riverine habitat for Astragalus robbinsii var. jesupii; one New Hampshire site has been protected by a conservation agreement with the landowner (U. S. Fish and Wildlife Service 1989).

    Elizabeth J. Farnsworth
    • 01/01/2010

    Studies of the effects of herbivores on survivorship and reproduction of Astragalus robbinsii var. jesupii Studies of the effects of invasive plant species on survivorship and reproduction of Astragalus robbinsii var. jesupii Quantitative population viability analysis from the monitoring data collected on populations Studies to determine the causes of poor seedling establishment at sites

    Elizabeth J. Farnsworth
    • 01/01/2010

    Germination and storage techniques are relatively well-known for Astragalus robbinsii var. jesupii

    MORE

    Be the first to post an update!

    Nomenclature
    Taxon Astragalus robbinsii var. jesupii
    Authority Eggl. & E. Sheld
    Family Fabaceae
    CPC Number 480
    ITIS 192747
    USDA ASROJ
    Duration Perennial
    Common Names Jesup's milkvetch | Robbins milkvetch | Jesup's milk-vetch
    Associated Scientific Names Astragalus robbinsii var. jesupii | Astragalus jesupii | Astragalus jesupii | Astragalus robbinsii var. jesupi | Atelophragma jesupii
    Distribution Astragalus robbinsii var. jesupii is known only from Vermont and New Hampshire (Brackley and Thompson 1985, NatureServe 2001).
    State Rank
    State State Rank
    New Hampshire S1
    Vermont S1
    Ecological Relationships

    Photos

    This 20-60 cm tall legume has small (1 cm across) violet flowers and compound leaves w/ 9-17 leaflets. Photo Credit: Arieh Tal

    Photo Credit: Lisa Mattei
    Videos
    Conservation Strategies for Globally-Rare Endemic Jesup's Milk Vetch
    Pollinators
    Common Name Name in Text Association Type Source InteractionID
    Bees
    Bumble bees Bombus Floral Visitor Link
    Reintroduction
    Lead Institution State Reintroduction Type Year of First Outplanting
    New England Wild Flower Society Vermont Reinforcement 2012
    New England Wild Flower Society New Hampshire Assisted Colonization 2014

    Donate to CPC to Save this Species

    CPC secures rare plants for future generations by coordinating on-the-ground conservation and training the next generation of plant conservation professionals. Donate today to help save rare plants from extinction.

    Donate Today