Summer Mushrooms

Over the last two months my life has been quite hectic, with a lot of traveling both within the US and abroad, and little time for mushrooms picking. After a long mushroom abstinence period I finally had the chance to foray for a couple of days here in Rockville (MD) and in Richmond (VA). To my surprise my block was full of mushrooms of all types, shapes and sizes and, because this is my first summer picking mushrooms here in Rockville, I am still getting to meet the local habitants.

Some of the mushrooms I found in my two forays were the edible Agaricus campestris (Pink Bottom), a variety of boletus (which I could not identify), a nice looking (and poisonous) Amanita pantherina, some giant, and supposedly edible, Calvatia craniiformis (Purple-Spored puff ball), a huge number of the somewhat ugly puff ball Pisolithus tinctorius, a nice cluster of Coprinus (I am not sure about which one) and a few other mushrooms which I could not identify by sight and did not have enough time to inspect carefully.  In Richmond I was happy to find a nice fairy ring at my friend's yard. These mushrooms were very abundant and in all stages of development (most of them getting a bit old and dry). Because my friends were very interested in figuring out if these yummy looking mushrooms were edible (they were a bit excited with the idea of eating them) I was very was glad to help. So here we go...


Date
07/28/2010

Location
Richmond, VA

Habitat
Growing on grass, gregarious, multiple mushrooms growing in lines (partial fairy ring)

Pileus
Conical with an umbo, light beige, dry, with concentric scales on top,  with approximately ~10-15cm of diameter, round, smell is non-distinctive

Hymenium
Gilled, free, with crowded gills, dark grey/green, with remnants of universal veil on the edge, lamellae are free and smooth

Stipe
White, central, slender, long, equal, hollow, with superior,  dark, fringed ring

Spore print
Green

Impressions

These beautiful mushrooms are the very common Chlorophyllium molybdites Massee, a.k.a Green-spored Parasol. It is commonly found in lawns during the summer and fall, specially after rainy periods.  It is poisonous and contains type 8 toxins, which cause severe gastrointestinal upset, which can last several hours and it is, perhaps, one of the most common causes of mushroom poisoning in the US. This mushroom is commonly mistaken for Macrolepiota rachodes (the Shaggy Parasol) and Macrolepioda procera (the Parasol Mushroom), which are considered excellent edibles. The distinctive characteristics of this mushroom (which it is worth knowing well) are that Chlorophyllium grows in fairy rings and that it has a green spore print while the other two Parasols do not. Keep in mind that the gills of Chlorophyllium do not become very green and that, if you are not sure about its identity, that you should make a spore print (this should not take more than one hour).

References
Roody, W.C. Mushrooms of West Virginia and the Central Appalachians (2003), Pg 64.
Miller, O.K. and Miller, H.H. North American Mushrooms - A field guide to edible and inedible fungi (2006), Pg 52.