Rick Kerrigan’s new book – AGARICUS OF NORTH AMERICA – has to be the go-to book to find out the latest info about the mushrooms in this genus……
Agaricus campestris complex – most common lawn Agaricus – often coming up in mid-summer and fall in the east in great numbers……A CHOICE EDIBLE whether it’s this species or one of the closely related cryptic species….
A short, squat mushroom – in grass – with smooth, white cap (but sometimes tannish, even somewhat scaly?) – with pink gills when young, chocolate brown gills when mature. Like all species of this genus the gills are FREE from the stem and there is a partial veil covering the young gills that breaks as the cap expands and remains as a ring (annulus) about the upper stem…….smell is mushroomy, not fragrant and not phenolic….
Agaricus bitorquis is the first Agaricus we see every spring – usually up and about in May – in playgrounds, wood mulch, hard-packed soil – a CHOICE EDIBLE mushroom…..
This species has a ring composed of 2 veils – one from the partial veil, the other from a universal veil, the two forming a duplex annulus near the bottom of the stem, not on the upper stem as in most other species…..smell is mushroomy…..
Agaricus crocodilunus – a name we now use for what we might otherwise call A. arvensis or A. macrosporus……a fall mushroom…..often in fairy rings…..yellowing on bruising AND smelling distinctly fruity…..in grass in urban / suburban areas
a CHOICE edible species !
Agaricus sylvicola – a woodland species – in late summer and fall – yellowing on bruising AND very fruity fragrant – a CHOICE edible species…..
Agaricus amicosus – a red-staining Agaricus – a woodland mushroom, under conifers, in the Rocky Mountains — bruises red, odorless or mushroomy – EDIBLE…..
Agaricus cf placomyces – a late summer/fall mushroom in urban/suburban areas – in mulch, grass – with a distinctly dark center on the caps AND a phenolic smell (when sniffed, sometimes rubbed first) AND – when the stem is cut open lengthwise, the inside base of the stem turns distinctly yellow (in a minute or two)……NOT A SAFE EDIBLE……reportedly causes GI upsets in some people……