Distribution: Occurring west of the Cascades crest in lowland western Washington; British Columbia to California,
Habitat: Swamps and bogs at low elevations.
Flowers: June-August
Origin: Native
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Bumblebees, bees, flies, beetles, moths, hummingbirds, sawflies
Evergreen shrubs 0.5-2 m. tall, the twigs puberulent and glandular-dotted.
Leaves alternate, evergreen, ovate to oblong-ovate, deep green on the upper surface and grayish-green and densely glandular on the lower, more or less revolute, 3-4 cm. long and about as broad.
Flowers many in short, terminal racemes; pedicels 1-2 cm. long; calyx small, 5-parted nearly to the base; petals 5, distinct to the base, white, nearly rotate; stamens 8-12, longer than the style, the anthers without awns, opening by pores near the tip; ovary superior.
Capsule 5-valved, ovoid to globose, 3-6 mm. long, puberulent and glandular.
PNW Herbaria: Specimen records of Rhododendron columbianum in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Rhododendron columbianum checklist entry
OregonFlora: Rhododendron columbianum information
E-Flora BC: Rhododendron columbianum atlas page
CalPhotos: Rhododendron columbianum photos