Distribution: Western Northern Hemisphere
Habitat: Occurs with alders
Conservation Status: Not of concern
Lactarius occidentalis is a small fragile species that occurs with alders. The cap is smooth to wrinkled, dry to moist, dark brown to brown with olive colors when fresh, sometimes developing orange-brown tones, non-zoned, and translucent-striate along the edge when fresh. The gills are pinkish cinnamon to pinkish tan, narrow, and close. The stipe is dry and dark brown to brownish orange or grayish brown. The latex is white to whey-like, mild, and may be sparse or absent, especially in older mushrooms. Cut or broken surfaces slowly become reddish brown.
L. obscuratus (Lasch: Fries) Fries is a closely related species that grows with alder in Europe.