Calocybe gambosa - St George's Mushroom

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Agaricales

Family: Lyophyllaceae (NB: some authorities include Calocybe in the Tricholomataceae.)

Appearing from April until June, Calocybe gambosa has the common name St George's Mushroom. It is a good edible species, distinguished from other pale species of springtime by its mealy smell.

Calocybe gambosa is usually the first of the large edible fungi to appear. (The common name derives from St George's Day, 23rd April, by which date this mushroom can usually be found.)

Identification Guide

	Cap 5 to 15cm diameter; initially almost spherical, becoming convex and sometimes almost flat; often misshapen but retaining an incurved margin. The cap surface is smooth and white with a light brown tinge that sometimes becomes tan with age. Firm and white, the cap flesh is prone to maggot infestation as the fruitbody ages, and so only fresh young specimens are worth collecting.
	Gills The sinuate gills are white, narrow and very crowded.
Stem	2 to 4cm wide and solid, usually curved and slightly thicker at the base, the stem is 3 to 7cm tall. There is no stem ring.
Spore print	White.
Odour/taste	Mealy odour and taste.
Habitat	In cropped pastures and mown roadside verges; occasionally in mixed woodland.
Season	April to June.
Occurrence	Infrequent.
Similar species	This mushroom could be confused with the deadly poisonous Inocybe erubescens, the Deadly Fibrecap, which can appear at woodland edges towards the end of spring; its pale pink gills (rather than white like those of Calocybe gambosa) are adnexed and they turn red when bruised. The mealy smell of Calocybe gambosa helps in its identification, but other white fungi occur later in the year that also have a mealy odour - for example, Clitopilus prunulus, The Miller, which has decurrent gills..