Slender Fleabane - Erigeron gracilis
(see State Rank Reason below)
State Rank Reason (see State Rank above)
See rank details.
- Details on Status Ranking and Review
Score1 - Moderate: Generally 10,000-100,000 individuals.
Score2 - Regional or State Endemic or Small Montana Range: Generally restricted to an area <100,000 sq. miles (equivalent to 2/3 the size of Montana or less) or Montana contributes 50% or more of the species’ range or populations OR limited to 2-3 Sub-basins in Montana.
Area of Occupancy
Score1 - Moderate: Generally occurring in 11-25 Subwatersheds (6th Code HUC’s).
Score0-1 - Low to Moderate.
ScoreNA - Rank factor not assessed.
Score0-1 - Low to Medium.
Score0 - Low Vulnerability: Species does not have any unusual or specific life history or biological attributes or limted reproductive potential which makes it susceptible to extirpation from stochastic events or other adverse impacts to its habitat and thus slow to recover.
Raw Conservation Status Score
4 to 6 total points scored out of a possible 16 (Rarity factors and threats only)
Fibrous-rooted perennial from slender branched caudex. Stems ascending, 5–20 cm. Herbage sparsely strigose, eglandular. Leaves basal and cauline; blades linear to linear-oblanceolate, entire, 1–8 cm long, becoming linear-lanceolate above. Heads radiate, solitary. Involucres hemispheric, 5–8 mm high; phyllaries in 2 or 3 series, strigose, eglandular. Rays 40 to 100, blue or purple; ligules 5–12 mm long. Disk corollas 3–5 mm long. Achenes ca. 2 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX
Endemic to southwest MT and adjacent ID and WY (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
Observations in Montana Natural Heritage Program Database
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
Meadows, grasslands, sagebrush steppe and rocky slopes primarily in the subalpine zone.
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus bifarius
, Bombus centralis
, Bombus fervidus
, Bombus flavifrons
, Bombus huntii
, Bombus melanopygus
, Bombus mixtus
, Bombus rufocinctus
, Bombus occidentalis
, and Bombus insularis
(Thorp et al. 1983, Wilson et al. 2010, Colla and Dumesh 2010, Koch et al. 2012).
- Literature Cited AboveLegend: View Online Publication
- Colla, S.R. and S. Dumesh. 2010. The bumble bees of southern Ontario: notes on natural history and distribution. Journal of the Entomological Society of Ontario 141:39-68.
- Koch, J., J. Strange, and P. Williams. 2012. Bumble bees of the western United States. Washington, DC: USDA Forest Service, Pollinator Partnership. 143 p.
- Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
- Thorp, R.W., D.S. Horning, and L.L. Dunning. 1983. Bumble bees and cuckoo bumble bees of California (Hymenoptera: Apidae). Bulletin of the California Insect Survey 23:1-79.
- Wilson, J.S., L.E. Wilson, L.D. Loftis, and T. Griswold. 2010. The montane bee fauna of north central Washington, USA, with floral associations. Western North American Naturalist 70(2): 198-207.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Ament, R.J. 1995. Pioneer Plant Communities Five Years After the 1988 Yellowstone Fires. M.Sc. Thesis. Bozeman, MT: Montana State University. 216 p.
- Culver, D.R. 1994. Floristic analysis of the Centennial Region, Montana. M.Sc. Thesis. Montana State University, Bozeman. 199 pp.
- Lesica, P. 1992. Vascular plant and sensitive plant species inventory for the Highland Mountains, Deerlodge National Forest. Unpublished report prepared for the Deerlodge National Forest. Montana Natural Heritage Program, Helena, MT. 21 pp. plus appendices, photographs.
- Lesica, P., M.T. Lavin, and P.F. Stickney. 2022. Manual of Montana Vascular Plants, Second Edition. Fort Worth, TX: BRIT Press. viii + 779 p.
- Vanderhorst, J.P. and P. Lesica. 1995a. Sensitive plant survey of the Tendoy Mountains in the Beaverhead National Forest, Beaverhead County, Montana. Unpublished report to the Bureau of Land Management, Butte District. Montana Natural Heritage Program, Helena, MT. 59 pp. plus appendices.