Helianthus rigidus (Cass.) Desf. var. subrhomboideus (Rydb.) Cronquist
[= Helianthus pauciflorus ssp. subrhomboideus]
Annotated by D. Leininger, 24 Aug 1978. Remarks: =H. r. subsp. subrhomboideus (Rydb.) Heiser. = H. laetiflorus Pers. At MONT. Verified: J. H. Rumely At MONT on 7 November 1995.

Montana: Big Horn County: 12.8 kilometers (8 miles) w X sw of Fort Smith and 8 kilomerters (5 miles) w X sw of Yellowtail Dam. Elev. 1520 m.
T6S R30E S20; MPM
Datum: NAD 27. Uncertainty: 805 meters. Coordinate Source: TRS2LL.
About an open-canopy stand of Pinus flexilis on a ridge; sandy -gravelly soil. Phenology: Flowers.

Wayne D. Olson s.n., Jul 22, 1976
MONT, Accession: 73361