Agrocybe rivulosa

Agrocybe cylindracea - Poplar Fieldcap

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Agaricales

Family: Strophariaceae

Unknown in Britain until 2003 and added to the British list in 2004, this fieldcap has become very common in southern England, where its spread has been entirely due to the practice of mulching flowerbeds using wood chippings. (If it is ever given a common name, that might well have to be the 'Woodchip Fieldcap'.)

Many other fieldcaps are found on woodchip mulch, but the wrinkled cap of this mushroom is a great aid to its identification.

Note: In some field guides this mushroom is recorded in the family Bolbitiaceae.

Identification Guide

Cap

4 to10cm across, hemispherical becoming broadly convex or flat; the pale ochraceous surface develops radial wrinkles linked by a network of cross-veins.

Gills

Adnate; initially creamy-grey, turning grey-brownas spores mature.

Stem

5 to 10cm long and 1 to 1.5cm dia.; hollow; tapering slightly towards the apex; white, turning a pale creamy-ochre with age; persistent, pendulous ring.

Spore print

Brown.

Odour/taste

Not distinctive

Habitat

In large trooping groups on woodchip and on compost heaps.

Season

June to October.  

Occurrence

Increasingly common.

Similar species

Agrocybe praecox, which occurs in spring and early summer, often grows in woodchip mulch; it is typically smaller and usually has a darker cap.