Ash Tree Bolete

Boletinellus merulioides



Pored, with a brownish, wavy cap, off-center stalk, and clearly defined pores. Grows scattered on the ground near ash trees. June–October. Cap slightly humped to flat to deeply sunken; yellowish brown to reddish brown; flesh is yellowish, sometimes turning bluish green; texture dry, dull, soft; margin is curved in when young, and spreading, wavy, and uplifted when mature. Pores large; shallow, uneven; light yellowish, bruising to dark olive; arranged in a radial pattern, and quite beautiful. The pores of the ash tree bolete adhere to the cap of the mushroom; most other boletes have easily detachable pores. Stalk thick; brownish, bruising reddish brown; texture dry solid, off-center. Spore print olive brown. Spores magnified are elliptical. There are no lookalikes in Missouri.


Cap width: 2–5 inches; stalk length: ½–1½ inches; stalk width: ¼–1 inch.

Habitat and conservation

Grows scattered on the ground near ash trees.

image of Ash Tree Bolete Distribution Map
Distribution in Missouri




Life cycle

Like other mushrooms, the capped, aboveground portion is a reproductive structure whose purpose is to make and release spores. Most of the time, the organism lives in the soil as a mycelium, a netlike system of fibers.

Human connections

The ash tree bolete can yield a dye to produce brown or orange-brown colors. Although this is an edible mushroom, it gets mixed reviews for its flavor.

Ecosystem connections

Speculation about this mushroom's possibly having a symbiotic relationship with certain species of aphids appears to be just that: speculation.