Search / Plant Profile / Astragalus microcymbus

Plant Profile

Skiff Milkvetch (Astragalus microcymbus)

View of the long, sprawling stems. Note the small, white flowers held in loose racemes. Photo Credit: Carol Dawson

Global Rank: G1 - Critically Imperiled
Legal Status: N/A
Family: Fabaceae
State: CO
Nature Serve ID: 155930
Lifeform: Forb/herb
Date Inducted in National Collection: 02/25/1988

Description:

Astragalus microcymbus is a freely branching perennial with large, inflated pods and grayish foliage. Its name means 'little boat', which refers to the fruits that resemble an inverted skiff. Its original discovery was very perplexing to Astragalus expert Dr. Barneby and University of Colorado botanist William A. Weber. On July 20th of 1945, Dr. Barneby found a few plants in Gunnison County, Colorado. He attempted to find enough for further studyafter 10 years of searching, Weber finally located more plants. They could not decipher how this species could have arrived in the area and projected that the species might have been introduced. Another botanist, Joseph Basin, disagreed but couldnt find any more populations until 1966. Now the species is believed to occur in and near the South Beaver Creek drainage.

Where is Skiff Milkvetch (Astragalus microcymbus) located in the wild?

Habitat:

Open sagebrush or juniper-sagebrush communities on moderately steep to steep slopes. Often found in rocky areas with a variety of soil conditions from clay to cobbles, gray to reddish in color. Elev. 7600-8400 ft (Spackman et al. 1997).

Distribution:

Colorado endemic (South Beaver Creek, Gunnison Co.). Currently there are no records from Saguache Co., but it is expected to be there because it occurs only three miles from the county line in simila

States & Provinces:

Skiff Milkvetch can be found in Colorado

Which CPC Partners conserve Skiff Milkvetch (Astragalus microcymbus)?

Denver Botanic Gardens

Not Sponsored

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

10/02/2020

The Denver Botanic Gardens are conducting studies on rare plant demography (the study of a species birth and death rates, age distributions, sex ratios, and population sizes) for this and other species in Colorado. (Dawson and Spurrier 1997)

Nature Serve Biotics

05/02/2017

Astragalus microcymbus is a narrowly restricted endemic from the Gunnison Basin, in south central Colorado. There are a total of about 10,000 individuals. Rabbit herbivory is heavy.

Carol Dawson

01/01/2010

Rabbit and insect herbivory.

Carol Dawson

01/01/2010

A total of about 10,000 individuals (Von Bargen et al. 1997).

Carol Dawson

01/01/2010

Carol Dawson

01/01/2010

There is no formal management plan.

Carol Dawson

01/01/2010

Population trends and reproductive ecology, especially in relation to herbivory would be useful to conservation efforts.