Western Quillwort - Isoetes occidentalis
Isoetes lacustris var. paupercula
State Rank Reason (see State Rank above)
Isoetes occidentalis is known from two locations in northwest Montana. Survey work to identify other locations, document population sizes, and determine threats is greatly needed.
Plants aquatic. Leaves to 20 cm, gradually tapering. Sporangia 3–6 mm long. Megaspores 0.4–0.8 mm wide (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX)
Alaska, British Columbia, and California, east to Montana, Wyoming and Colorado.
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)
- Literature Cited AboveLegend: View Online Publication
- Lesica, P., M. T. Lavin, and P. F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Pierce, John. 1998. Montana specimen of Isoetes occidentalis. Collection number 2136. Deposited at University of Montana Herbarium (MONTU). Missoula, Montana. Accessible at the Consortium of Pacific Northwest Herbaria.