Bog St. John'swort: Hypericum anagalloides - Plants matted, less than 10 cm high. Petals less than 6 mm long, about equal to the sepals. Stamens less than 50. Plants of very moist areas.

Scouler's St. Johnswort, Scouler's St. John's-wort, Western St. John's-wort: Hypericum scouleri ssp. scouleri (Synonyms: Hypericum formosum ssp. scouleri, Hypericum formosum var. scouleri) - Plants erect, generally over 10 cm high. Petals much greater than 6 mm long, much longer than the sepals. Stamens greater than 50. Sepals triangular to ovate-lanceolate in shape, less than 3X as long as wide. Plants with widespread stolons and rhizomes, but not with a taproot.

Common St. Johnswort, Common St. John's Wort, Klamathweed, Klamath Weed: Hypericum perforatum - Plants erect, generally over 10 cm high. Petals much greater than 6 mm long, much longer than the sepals. Stamens greater than 50. Sepals linear-lanceolate in shape, 3-5 times long as wide. Plants with taproot and some short rhizomes or stolons.