Barrow's Bolete
Boletus barrowsii
Barrow's Bolete (Boletus barrowsii) is a stout, pale king bolete with a whitish to pale tan cap, a thick stem covered by a fine net, and white flesh that does not change color when cut. In the Southwest and Colorado it grows mainly with ponderosa pine; iNaturalist's Black Hills records run from June into September, most often in July.
Free photos from other sources
| Family | Boletaceae · Bolete |
|---|---|
| Type | Bolete |
| Season | June into September, most often in July |
| Size | Cap 5–16 cm (2–6½ in) wide, stem 5–15 cm (2–6 in) tall and 2–5 cm (¾–2 in) thick |
| Grows on | Soil under ponderosa pine |
| Spore print | Olive brown |
| Also called | White King Bolete |
| Eating | This guide doesn't say which mushrooms are safe to eat. |
How it lives
Mycorrhizal: it trades nutrients with the roots of living trees, mainly ponderosa pine in the Rocky Mountains and the Southwest. It is a pale close relative of the King Bolete (Boletus edulis). Alexander Smith and Harry Thiers named it in 1976 for Chuck Barrows, the amateur mycologist who first noticed it. Insect larvae often tunnel through the mushrooms.
How do you identify Barrow's Bolete?
The cap is dry, dull and smooth, whitish at first and pale brownish with age, 5–16 cm (2–6½ in) wide. Under the cap are pores, not gills. On young mushrooms the pore openings are plugged with white tissue, so the underside looks smooth and white; it turns yellow, then olive-yellow, and does not bruise. The stem is thick and club-shaped when young, whitish, with a fine net over the top part or nearly all of it. Cut flesh is white and does not turn blue or change color. Ruby Porcini shares the fine net, the white young pores and the white flesh, but its cap is dark red to red-brown. Aspen Bolete has dark scabers (rough scales) on the stem instead of a net, and its flesh slowly darkens to a dusky grayish brown when cut. Slippery jacks have a sticky to slimy cap and, usually, tiny glandular dots on the stem instead of a net.
When can you find it?
June into September, most often in July.
Where does it grow?
On the ground, alone, scattered or in groups, often at the edges of ponderosa pine stands rather than in deep woods. In the Southwest and Colorado it partners mainly with ponderosa pine and sometimes spruce; on the West Coast it grows with coast live oak. In the Black Hills, iNaturalist has 24 records, 12 confirmed by other observers, from Pennington, Custer, Lawrence and Meade counties, including Custer State Park and Wind Cave National Park, where an observer noted ponderosa pine. Mushroom Observer has one more Black Hills record, from June 2018. No herbarium specimen or published Black Hills report was found.
Other mushrooms to compare
Sources: Kuo, M. 2022. Boletus barrowsii — MushroomExpert.com; Volk, T. J. 2004. Boletus barrowsii, Chuck Barrows' bolete. Tom Volk's Fungus of the Month — University of Wisconsin; Arora, D. & J. Frank 2014. Boletus rubriceps, a new species of porcini from the southwestern USA. North American Fungi 9(6) — Washington State University Research Exchange; Thiers, H. D. 1975. The Boletes of California: Leccinum insigne var. insigne — MykoWeb; Kuo, M. 2023. Suillus — MushroomExpert.com; Boletus barrowsii observations in the Black Hills places, Wind Cave and Custer State Park — iNaturalist; Boletus barrowsii observations in the Black Hills box — Mushroom Observer; Boletus barrowsii Thiers & A.H. Sm. — Catalogue of Life (Species Fungorum), via ChecklistBank; Boletus barrowsii taxon names — iNaturalist.