Marsh Felwort - Lomatogonium rotatum
State Rank Reason (see State Rank above)
Only two known occurrences in Montana on BLM and private lands, including one moderate-sized population. Livestock grazing occurs in the occupied habitat, though it is unclear what effect it may have on L. rotatum. Changes in the hydrology, particularly lowering of the water table may adversely affect populations.
Felwort is a glabrous annual with usually unbranched stems that are 5-15 cm high. The opposite leaves are narrowly oblong to lance-shaped and 1-3 cm long. White or bluish flowers are borne on slender, 1-3 cm long stalks which arise from the axils of the upper leaves. The 5 spreading, lance-shaped petals are 6-15 mm long and are united at the base and subtended by slightly longer, narrow, green sepals. Each petal has 2 small appendages at the base, and there are 5 stamens. The fruit is a many-seeded, egg-shaped capsule that is as long as the petals.
Flowering in August.
Swertia perennis has similar flowers but is a perennial. Annual gentians have tubular rather than star-shaped corollas. This plant is often overlooked because it blooms in August.
Greenland to Alaska, south to Colorado.
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)
Alkaline meadows and fens in the montane zone.
Ecological Systems Associated with this Species
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Famous, N. C. and C. S. Campbell. 1984. Lomatogonium rotatum (Gentianaceae) and Primula laurentiana (Primulaceae) in Maine: New locations and general distribution. In prep.
- Famous, N. C., and C. S. Campbell. 1985. Lomatogonium rotatum. In: The Nature Conservancy Element Stewardship Abstract [Data base]. Boston, MA: The Nature Conservancy, Eastern Regional Office.
- Lesica, P. In progress. Notes on new additions to Montana flora.
- Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
- Lesica, P., P. Husby, and S. V. Cooper. 1998. Noteworthy collections: Montana. Madrono 45:328-330.