A Giant Mushroom

About two weeks ago, while taking my daughter to the playground I spotted a cluster of giant mushrooms growing on a lawn near the park. Indeed, these mushrooms were so big that I initially thought they were something else. Because I did not have time to examine the specimen for a few days, I kept it in the fridge for almost a week (despite my wife's protest ;-).  Given the size of this fungi and the fact that it looked like a puff ball I was optimistic this one was going to be an edible and that it was going to feed me for a couple of days.


Description

Date
08/22/2010

Habitat
Gregarious (three specimens close to each other), growing on grass, under oak

Fruiting body
Pear shaped, very large, beige, dry, smooth, glabrous, wrinkled, leathery, approximately 110 mm wide at top and 140 mm of high. Odor is non-distinctive. When cut, it was possible to observe that the cuticle was quite thick and that the gleba was spongy and olive/beige.


Spore print
Not obtained

Impression
This is a specimen of Calvatia craniiformis (Schwein.) Fr., which is considered to be a very fine edible, when the gleba is pure white (not the case here). By the time I inspected it was already past its prime time and therefore was not edible anymore. I'm not sure why, but the Falcon Guide to North American Mushrooms recommends that they should be kept for one day at the refrigerator before eating. Because the genus Calvatia does not present any mushrooms with toxins and because the identification is quite easy I would think that this might be a good mushroom for beginners interested in picking edibles.