Potamogeton zosteriformis Fernald

Montana: Lincoln County: Kootenai National Forest, Rainbow Lake, 24 mi N of Libby, MT off FS rd 68. Elev. 1292 m.
T33N R31W S6 S 1/2
Datum: WGS 84. Uncertainty: 1138 meters. Coordinate Source: Calc. from TRS. Updated PLSS locality from R32W to R31W.
Ca. 7 hectare lake surrounded by a floating Sphagnum mat on the E side and non-floating sedge fen on the S, W, and N that covers an additional 7 hectares. Littoral regions of lake characterized by scattered clumps of Potamogeton amplifolius and Nuphar variegatum (neither very dense). Floating mat dominated by dense stand of Carex lasiocarpa, Menyanthes trifoliata, and C. muricata. Sphagnum cover well-dev. in places, absent in others. Slightly raised, hummocky peatland margins dominated by C. lasiocarpa, C. lenticularis and Calamagrostis canadensis. A stand of 7 m high Alnus incana borders peatland/upland forest. Forest mixed w/ Pien, Pico, Laoc, and few Abla. Water chem: (mg/l) hardness 25.8 (CaCO3) Ca 6.2, Mg 2.4, K 0.8. Abundance: common, forming a thick rhiz. patch w/ P. amplifolius in ca 1.25 m of water adjacent to the mat. Water clear to bottom.

R. Bursik 1151, Jun 25, 1988
With C. Clemens
ID, Accession: 105662, Barcode: ID006838