Clasping Groundsel - Senecio amplectens
State Rank Reason (see State Rank above)
In Montana, only known from the Beartooth (Line Creek) Plateau. Additional data on population size, trends and potential threats are needed to evaluate the species' vulnerability.
- Details on Status Ranking and Review
Score3 - Vey Small: Generally <2,000 individuals.
Score1 - Peripheral, Disjunct or Sporadic Distribution in MT: Widespread species that is peripheral, disjunct or sporadically distributed within MT such that it occurs in <5% of the state (<7,500 sq. miles or the combined area of Beaverhead and Ravalli Counties) or is restricted to 4-5 sub-basins.
Area of Occupancy
Score3 - Very Low: Generally occurring in 3 or fewer Subwatersheds (6th Code HUC’s).
Score1-2 - Moderate to High.
Score0-3 - Population trends are unknown.
Score2-3 - High to Very High.
CommentKnown population may be detrimentally impacted by adjacent road and related activity.
Score1 - Moderate Vulnerability: Specific biological attributes, unusual life history characteristics or limited reproductive potential makes the species susceptible to extirpation from stochastic events or other adverse impacts to its habitat and slow to recover.
Raw Conservation Status Score
11 to 16 total points scored out of a possible 19.
Clasping Groundsel is a glabrous herb with several lax to ascending stems that are 1-2 dm tall and arising from a short rhizome and fibrous roots. The few narrowly elliptic basal leaves are 5-18 cm long and have petioles and coarsely toothed margins. The alternate stem leaves are similar but smaller upward, and the uppermost lack petioles. Flowers are borne in 1-3 terminal, nodding heads. The heads have a single series of ca. 21 non-overlapping, narrow, pointed, involucral bracts that are 10-15 mm long. Disk flowers are yellow, and the 8-13 yellow rays are 1-2 cm long. The achene is glabrous with a pappus at its summit.
Flowering in late July-early August.
Senecio is a large genus, and a technical manual should be consulted for positive identification. The rocky alpine habitat and 1 to a few nodding heads help distinguish this species from others.
Known from Carbon County. MT to NV, UT and NM (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
Observations in Montana Natural Heritage Program Database
Number of Observations:
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Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
Stony, open soil and talus of slopes in or near the alpine zone.
Ecological Systems Associated with this Species
- Commonly Associated with these Ecological Systems
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus bifarius
, Bombus flavifrons
, Bombus frigidus
, Bombus huntii
, Bombus melanopygus
, Bombus mixtus
, Bombus sylvicola
, Bombus occidentalis
, Bombus insularis
, Bombus suckleyi
, Bombus flavidus
, and Bombus kirbiellus
(Schmitt 1980, Thorp et al. 1983, Mayer et al. 2000, Wilson et al. 2010, Pyke et al. 2012, Koch et al. 2012, Williams et al. 2014).
Threats or Limiting Factors
STATE THREAT SCORE REASON
Threat impact not assigned because threats are not known (MTNHP Threat Assessment 2021).
- Literature Cited AboveLegend: View Online Publication
- 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.
- Mayer, D.F., E.R. Miliczky, B.F. Finnigan, and C.A. Johnson. 2000. The bee fauna (Hymenoptera: Apoidea) of southeastern Washington. Journal of the Entomological Society of British Columbia 97: 25-31.
- Pyke, G.H., D.W. Inouye, and J.D. Thomson. 2012. Local geographic distributions of bumble bees near Crested Butte, Colorado: competition and community structure revisited. Environmental Entomology 41(6): 1332-1349.
- Schmitt, J. 1980. Pollinator foraging behavior and gene dispersal in Senecio (Compositae). Evolution 34: 934-943.
- 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.
- Williams, P., R. Thorp, L. Richardson, and S. Colla. 2014. Bumble Bees of North America. Princeton, NJ: Princeton University Press. 208 p.
- 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.