short, fat, flatten base, and thick double ring like annulus. These tent to be found grow, pushing from the soil. A. campestris seem to have that pointy or skinnier base. Smaller than A. bitorquis overall
Elena Portz
2016-02-00
Mon Feb 01 2016 15:27:02 GMT-0800 (PST)
United States of America, California, Stanford Arboretum, Stanford, CA, US
no fibrils on cap mild orange staining on base of stem gills pink in button stage (see picture) which is why I did not ID these mushrooms as agaricus californicus. However, all my buttons are full of maggots and and somewhat old, so perhaps they were once white. I found these mushrooms on a little strip of earth in between a sidewalk and a driveway in the middle of a grove, so this would hint at agarics californium (according to the Aurora book).