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Fringed Onion - Allium fibrillum
(see State Rank Reason below)
State Rank Reason (see State Rank above)
See rank details.
- Details on Status Ranking and Review
Score0 - Large: Generally >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).
Score1 - Moderate: Species is restricted to a specific habitat that is more widely distributed or to several restricted habitats and is typically dependent upon relatively unaltered, good-quality habitat (C Values of 5-7).
Score0-1 - Stable to Minor Declines:
CommentTrends unknown, though populations are likely stable or experiencing only minor declines.
Score1 - Medium: 11-30% of the populations are being negatively impacted or are likely to be impacted by one or more activities or agents, which are expected to result in decreased populations and/or habitat quality and/or quantity.
CommentInvasive weeds may threaten some populations.
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
5 to 6 total points scored out of a possible 19.
Bulbs globose to ovoid, usually solitary; outer coat membranous with obscure, contorted reticulations. Scapes terete, 3–15 cm. Leaves 2(–4), nearly flat, 1–3 mm wide, barely persistent. Umbel hemispheric with 10 to 20 flowers; pedicels 5–12 mm long; bracts 2, ovate, apiculate. Flowers white with green midveins; tepals 5–10 mm long; ovary with 3 low crests; stamens included. Seed surface smooth (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX
Flowering June-early July.
The only other onion in northwest Montana that is usually less than 15 cm tall with only 2 leaves is A. textile, which has 3 bracts below the flower cluster and bulb coats that are very fibrous, resembling burlap.
Eastern OR and southeast WA, adjacent ID, and northwest MT. Regional endemic.
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)
Shallow, seasonally moist soils in the montane 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 flavifrons
, Bombus huntii
, Bombus melanopygus
, Bombus sylvicola
, Bombus occidentalis
, and Bombus bohemicus
(Macior 1974, Thorp et al. 1983, Colla and Dumesh 2010, Koch et al. 2012, Miller-Struttmann and Galen 2014, Williams et al. 2014).
- 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.
- Macior, L.M. 1974. Pollination ecology of the Front Range of the Colorado Rocky Mountains. Melanderia 15: 1-59.
- Miller-Struttmann, N.E. and C. Galen. 2014. High-altitude multi-taskers: bumble bee food plant use broadens along an altitudinal productivity gradient. Oecologia 176:1033-1045.
- 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.
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