West Coast reishi is a bracket fungus that looks as if someone painted it with varnish. Its shelf-like cap can grow large, from about 10 to more than 50 cm across, in a rough half circle or kidney shape. The top has a shiny, lacquered crust in mahogany to reddish brown, sometimes with a few paler zones, while the underside is a pore surface that starts whitish and turns brown with age, darkening wherever it is touched. Some specimens have a short, stubby stem off to one side.
Although it looks woody, each conk is annual. It appears in fall and can last through winter into spring. It mostly feeds on dead conifer wood, breaking it down with a white rot, but it can also enter living trees through wounds. That slow work helps turn fallen and standing dead trees back into soil. The flesh is tough and whitish to cream, and the spores are reddish brown.
On Mt. Hood, look for it on standing dead conifers, stumps and logs in moist forest, from fall through early spring. It closely resembles its eastern relative Ganoderma tsugae. The two were once thought to share the Pacific Northwest, but recent DNA studies did not support that, and the West Coast reishi appears to be the only lacquered Ganoderma on conifers here.
How to identify it
A large, shelf-like conk 10 to 50 cm or more across with a shiny, lacquered, reddish brown to mahogany top. Pore surface whitish when fresh, aging brown and bruising darker. Flesh tough, whitish to cream, without dark bands. It grows on conifer wood and sometimes has a short, lacquered side stem.
Look-alikes
Ganoderma tsugae is nearly identical but is mainly an eastern species with smaller spores. Ganoderma polychromum shares the West Coast but grows on hardwoods and has brown flesh.
Habitat
Dead standing conifers, conifer stumps and logs, and wounds on living conifers in forests of the Pacific Northwest and California. Fruits from fall through spring.
Sightings in the forest
96 research-grade sightings in Mt. Hood National Forest on iNaturalist, most recently on October 31, 2026. See them on iNaturalist →