Almond Mushroom, Royal Sun Agaricus, Himematsutake
1 public strain
Agaricus subrufescens, the almond mushroom, is a large Agaricus with an almond odor and a cap that turns yellow with KOH. Charles Peck described it in 1893 from the northeastern United States, where it was grown for the table in the late 1800s and early 1900s. It was rediscovered in Brazil in the 1970s, misidentified as A. blazei, and is now cultivated commercially, chiefly in Brazil, and sold as a medicinal mushroom.
Edible for most people, with a somewhat sweet taste. Some people have had allergic reactions, and preliminary reports link Agaricus supplements to raised liver enzymes. Wild collectors must rule out poisonous yellow-staining Agaricus such as A. xanthodermus (phenol odor) and deadly white Amanita species (white gills, white spore print, volva).
Never eat a wild mushroom based on a web page — confirm with an expert.
Mycology is an evolving science: names, classifications and safety information change as research advances. Entries are compiled from cited sources and reviewed, but may be incomplete or out of date — check the sources, and never rely on this library alone to identify or eat a mushroom.
Habitat
Saprotrophic, growing singly or in clusters in leaf litter on rich soil, often in gardens and other domestic settings. Cultivated commercially on pasteurized compost with a soil casing.
Distribution
Originally described from the northeastern United States and Canada; also recorded from California, Hawaii, Great Britain, the Netherlands, Taiwan, Japan, the Philippines, Iran, Australia, Brazil and Uruguay. Cultivated mainly in Brazil.
Characteristics
Cap: 5–25 cm; hemispherical becoming convex; white to greyish or dull reddish brown; silky-fibrous, later finely scaly; yellow with KOH. Gills: Free; white, then pink, then blackish brown. Stem: 6–15 cm long, 1–4 cm thick; sometimes bulbous, becoming hollow. Ring: Double-layered. Flesh: White; taste like green nuts. Odor: Of almonds (benzaldehyde, benzyl alcohol, benzonitrile, methyl benzoate). Spore print: Brown; spores ellipsoid, smooth, 5.5–7 × 4–5 µm.
Difficulty
Advanced
Substrates
Two-phase pasteurized compost (grass straw and sugarcane bagasse in Brazil) · Soil casing layer
