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.

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.

Mushroom picking in Finland

Yesterday I went mushroom picking in the outskirts of Helsinki and it was a lot of fun. It hasn't being raining a lot and the temperatures in Helsinki this year are extremely hot for Scandinavian standards (>30C). In spite of that, I was able to find plenty of chanterelles (Cantharellus cibarius), a nice Russula (Russula sp) and some hedgehog mushrooms (Hydnum hepandum). My friends weren't too excited with the hedgehogs and said that they didn't enjoy them very much. The Russula, as usual, is too difficult to identify to be considered edible. On the other hand, Finish people love chanterelles, and the fact that one can already fill a basked with them, even on a short walk, seemed to make my friends hearts beat a bit faster...

One thing I liked about mushroom picking in Finland is that the typical vegetation is composed mostly of coniferous forests, for that, the hunting is very easy and the mushrooms pop out of the green moss which contrasts well with their color. The funny thing is that the chanterelle season hasn't officially started here (it starts in August) and every Finn I talked to told me that it was too early to go after them.  On the other hand, because my host knows of a nice chanterelle spot behind her garage, she has been watering it everyday and there were hundreds of chanterelles growing there (no need to go into the forest ;-). Also, the very hot and humid weather (despite the little rain) may be helping the mushrooms to fruit as well.

If one is really into eating chanterelles (why one wouldn't be???) but is not into the mood of picking them (or does not have the time to go into the woods), all that is necessary is to go to one of the many open markets around here and buy a couple liters of fresh wild mushrooms (yup, chanterelles are sold in buckets here). The price doesn't vary a lot from stand to stand but it decreases somewhat linearly with increasing quantities (1 liter = 5 Euros, 2 liters = 8 Euros, 3 liters = 10 Euros). Right now the chanterelles sold on the markets come from Estonia, which is just a few miles south of Finland and which is a little bit warmer (I highly recommend taking the boat and spending at least one day in Tallin). To be sincere I went kindda crazy with this abundancy of chanterelles and for the first few days of my trip I lived on an almost chanterelle-exclusive diet ;-). Other mushrooms which are commonly sold in markets here (albeit dry or canned at this time of the year) are Gyromitras, black chanterelles (Craterelus cornucopiodes) and porcini (Boletus edulis). Although all my mushroom picking guides don't recommend eating Gyromytras, my friends here eat them frequently and don't seem to be too scared by them or the skull label (required by law), which is always visible in the packaging whenever you buy them (they cook them for a long time and change the water at least three times).

On a last note, apparently mushroom picking is an extremely common hobby in Finland (and other neighboring countries) and pretty much every Finn knows how to pick at least a couple of mushroom species (chanterelles being definitely the most common). This hobby is somewhat inserted into the Finish culture of camping and going into the wild and it is passed from generation to generation. My friends tell me that in August, the woods around Helsinki get full of people with their baskets, and that it is almost impossible to find mushrooms near the most beaten paths. Because of that, Finns are very secretive about their chanterelle spots and are not that willing to share their location.

Why join your local Mycological Association?

Some weeks ago I went for the first time to the Mycological Association of Washington (MAW) monthly meeting at the Chevy Chase Public Library (it is usually there and at the first Tuesday of each month, but you feel like going please check on Meetup.com first to make sure they haven't changed the venue). The meeting usually starts at 7 pm and it is a great opportunity to learn more about mushrooms, get to know other mycophiles from all ages and experience levels, and learn about all the mushroom related activities in the surroundings. Every meeting people take their recent findings, either to get an educated opinion about identification, or just for the sake of showing off to other people. On the last meeting there were a huge variety of mushroms, including jelly ears (Auricularia auricula), meadow mushrooms (A. campestris), reishi mushrooms (Ganoderma lucidum), Boletus fraternus, Thick Maze Oak Polypore (Daedaleopsis quercina) and a large variety of unidentified mushrooms.

In many ways, the meeting reminded me of the Bambui (a very nice Spelunking group in my hometown) meetings I used to go. The format is a little bit more formal, but still informal enough to make it enjoyable. The current president (Ray LaSala) makes sure everything that needs to be reported gets reported. Also, there was a section on mushroom identification by one of the former presidents, which displayed most of the field guide available and discussed the pros and cons of each one (really useful information). Last, there was a slide section with hundreds of mushroom images with nice commentary by a former president of MAW and time for questions. Really good stuff!

A "stinky" Russula

I have found these Russulas growing on mulch and grass  in my block over the last month. To me, they are not very nice looking mushrooms and, every time I found them, they were braking apart or destroyed by the lawn mowers. Last week I found some clusters that were in good shape and decided to take some home to see if I could determine their identity. On a closer look, the characteristics that stand out on these mushrooms are the strange spermatic smell, the yellow cuticle, and the compressed (shaped like a compressed tube) wide white stipe (stem). Unfortunately, when I collected this mushroom I did not know how difficult it is to identify Russulas and, therefore, did not pay enough attention to some of the important details for this hard task (spore shape and size, cap cuticle separability etc). Indeed, there are many identification keys around the internet, and each one is a little bit more confusing then the other. While searching for information on how to identify my specimens I came across a nice webtool for North American Russulas identification on the Museo Tridentino de Scienze Naturali website, which I highly recommend. Other options are the Pacific Northwest Key Council website (which by the way is a great place for getting identification keys for all North American mushrooms). Last, for specific information on stinky Russulas, there is the key MushroomExpert.com key.

Location: Rockville, MD
Habitat: Gregarious, growing on grass, under conifers

Measurements
Pileus diameter - 42 x 54 mm | 46 x 48 mm
Pileus height - 22 mm | 15 mm
Stipe length - 40 mm | 43 mm
Stipe diameter at apex - 13 x 15 mm | 13 x 12 mm

Stipe diameter at middle - 13 x 20 mm | 13 x 16 mm
Stipe diameter at base - 13 x 20 mm | 15.5 17.5 mm

Description
Pileus - Yellow/brown, dry, glabrose, cracking, smooth, convex on young specimens and becoming depressed on older ones, round, margin inrolled on young speciments and upturned in older ones, flesh is white, brittle, smell is spermatic
Hymenium - white, gilled, gills are crowded/close, smooth, adnate
Stipe - white, compressed, varying from equal to clavate, hollow with floccose contents, inserted, with brown stain at the base

Impressions
This looks like a member of the foetid Russula family, possibly R. foetens. Nevertheless, identifying Russulas is not an easy task and, given my naivete when collecting data on this mushroom, I had a hard time identifying it. Some possibilities would be R. amoenolens (a common foetid Russula in North America) which has been described to appear in the region where I live, but the "spermatic" smell seems to be a characteristic of R. foetens (hence the latin name foetens, which means stinky). Many of the characteristics of the mushroom also match R. laurocerasi, R. foentetula, R. and fragrantissima. For now, I'll have to classify it only as Russula sp.

Amanita volvata?

This morning I went on a foray organized by the Mycological Association of Washington at the Rock Creek Park in Washington, DC. The park is a great place for finding mushrooms and the foray was very agreeable. It rained a lot this last week and therefore there were many mushrooms growing, specially slime molds and polypores. Some of the specimens I remember were the long Xerula furfuracea,  the buggy Megacollybia platyphylla, White Coral Slime (Ceratiomyxa fruticulosa),  Stalked Scarlet Cup (Sarcoscypha occidentalis), Red Raspberry Slime (Tubifera ferruginosa), Turkey Tail (Trametes versicolor), Artist's Conk (Ganoderma applanatum), Coal Mushroom (Daldinia concentrica) and a nice cluster of three amanita mushrooms that we thought could be American Amidella (Amanita volvata) and which I decided to bring home to analyze more carefully (I brought home only one and I chose the intermediate sized one, which I used for the description below). 

As all Amanitas, this one had a volva (sac of tissue around the stem base), but contrary to most of them, this one did not have a ring around the stem. Mycologists use this information to help classify mushrooms, and since most amanitas are lethally toxic when eaten (with as small number of exceptions), one should pay a lot of attention to every detail when trying to identify amanitas, specially the presence or absence of rings and volvas. Other things that we noted immediately on these mushrooms was the large size (the biggest one had a cap that was probably 15 cm wide or wider) and the white color. On a more careful examination we observed that the mushroom bruised red/pink and that the gills under the cap were white. All these characteristics (and the ones described below) could suggest a member of the Amanita section Amidella.


After posting my photos and description at Mushroom Observer,  Dr. Rodham Tuloss (an Amanita mycologist which has a very good website on Amanitas) sent me some comments and pointed out that "Amidellas are very hard to determine from a picture or even with one in your hand" and that ones has to rely on a microscope. Therefore for now I'll call this specimen just Amanita sp.

If this mushroom were indeed A. volvata, it would be a non-edible mushroom (as most Amanitas). 

 

Habitat
Growing on soil, near dead wood, gregarious, cluster of two specimens very close to each other and another approximately 50 cm away.

Description
Pileus – white, dull, dry, with remnants of the universal veil (appressed scales), bruises initially light red and then becomes brown very slowly, round, convex to flat, flesh is white, margin is striated.
Hymenium – gilled, gills are white, crowded, free, smooth, margin is entire, crenate.
Stipe – white, hollow with cottony cluster inside, cartilaginous, tapered toward apex, with white and elongated volva at the base, flocose near apex, inserted, smell is weak and non-distinctive.

Measurements
Pileus height – 22 mm
Pileus diameter – 48-50 mm
Stipe diameter at apex – 8 mm
Stipe diameter at middle – 9.5 mm
Stipe diameter at base – 13 mm
Stipe length – 120 mm
Volva height – 4.5 cm

 

An edible Amanita that I'll not eat

This is the second mushroom I found on my walk today. The shiny silver metallic cap caught my attention. When I moved the grass aside to see the base of it, to my surprise I found a bright white volva and a white stem, therefore suggesting a mushroom from the Amanita genus.

Date: 06/07/2010
Location: Rockville, MD
Habitat: growing on grass, two specimens close together


Measurements
Pileus diameter - 30 mm
Pileus height - 21 mm
Stipe length - 70 mm
Stipe diameter at apex - 6.7 mm
Stipe diameter at middle - 6.7 mm
Stipe diameter at base - 6.7 mm

Description
Pileus - metallic gray, glabrous, round, convex, margin entire, striated, flesh is white, does not bruise any color, smell is non-distinctive
Hymenium - white, gilled, gills are close, free, narrow, smooth/finely serrulated
Stipe - white, central, somewhat compressed, hollow, equal, with white volva, no ring, flexible, inserted
Spore print - white

Impressions
This looks like Amanita vaginata, one of the few edible amanitas. The white spore print, the presence of a white volva, metallic gray cuticle, absence of a ring and the white free gills are all very suggestive of this species. Despite the reasonably easy identification I am not brave enough to eat it and would not suggest anyone eating it. Amanitas cannot be taken lightly and a single mistake is often fatal (causing a painful and long death due to liver insufficiency which is only treatable by liver transplantation). Unless you are 100% sure of the identification, you should never ever eat amanitas (unless it is a cultivated species and you are buying it from a reliable commercial vendor). The other famous edible amanita is A. cesarea (Cesar's amanita) which is also reasonably easy to identify, but which also requires the utmost care.