Water Birch: Betula occidentalis
Bog Birch, Dwarf Birch, Swamp Birch, Resin Birch, Scrub Birch: Betula glandulosa (Synonyms: Betula glandulosa var. glandulosa, Betula terrae-novae) - Native shrub of moist areas at mid- to high elevations.
Water Birch, River Birch, Red Birch: Betula occidentalis - Native tree or shrub of moist areas and streambanks at low elevations.
Canoe Birch, Paper Birch, Western Paper Birch, White Birch: Betula papyrifera (Synonyms: Betula alba var. commutata, Betula montanensis, Betula papyrifera var. commutata, Betula papyrifera var. subcordata) - Native Tree of moist, open to dense woods at low to moderate elevations.
European White Birch, European Weeping Birch: Betula pendula - Introduced ornamental tree.
Bog Birch, Dwarf Birch: Betula pumila (formerly Betula glandulosa var. hallii) - Native shrubs of the high Oregon Cascades but also found in southwestern Lake County, OR.
Hybrid Shrubby Birch: Betula xsargentii - Shrub found in southwestern Lake County, OR.