Xerocomus subtomentosus (“Yellow Crack Bolete”)

Olive- to yellow-brown cap often fissures & cracks w/age. Yellow stem has red-brown streaks, sometimes ridges, & often stains brownish from handling. Ammonia on cap turns red/brown.

SKU: Boletus subtomentosus Categories: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Description

Name in North American Boletes: Boletus subtomentosus

Genus: Xerocomus

  • Genus 2: Boletus

Species: subtomentosus

Common Name: “Yellow Crack Bolete”

Tells: Olive- to yellow-brown cap often fissures & cracks w/age. Yellow stem has red-brown streaks, sometimes ridges, & often stains brownish from handling. Ammonia on cap turns red/brown.

Other Information: Yellow pores dull w/ age & stain greenish to greenish-blue, often lightly and slowly.

Science Notes: North American Boletes lists a parallel species called var. perplexus. DNA tests have merged this back into the parent, along with moving the whole thing over to the newly erected genus “Xerocomus”. The var. perplexus cap was supposed to be a little lighter, with more consistent staining in the pores.

Edibility: Good.

CHEMICAL TESTS:

  • NH4OH (Ammonia): Cap skin instantly turns reddish brown.
  • KOH: No data in N.A.B. Per Dave Wasilewski in Pennsylvania, cap skin turns blackish brown & resolves to brown, while cap flesh turns grayish & then resolves to pale amber.
  • FeSO4 (Iron Salts): No data.

Links:

National Audubon Society Field guide to Mushrooms, Gary Lincoff572Mushrooms of West Virginia and the Central Appalachians317North American Boletes166165

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