Inky Cap

You may recognize this picture from the What is it? question on the October 31 blog.  We found this mushroom at the head of the trail at the Watershed Center, just in time to introduce it to the 4th graders who were starting their Nature Unleashed program last month.  The underside produces a black "inky" liquid full of spores.  By the time all the kids were through, there were a lot of black fingers.  This was fine with the mushroom as the students were all going out, spreading its spores.  After all if you are a mushroom, isn't that what it is all about?

Click to enlarge

This beauty is a shaggy mane, Coprinus comatus, also called shaggy ink cap or lawyer's wig.  It is edible but can be confused for a toxic cousin so I wouldn't eat one without a more expert consult.  If you were to pick it, it must be cooked in 4-6 hours as it begins to autodigest immediately, leaving just what it sounds like, an inedible mess. 

These are commonly found on lawns or green meadows.  When they first appear, they are white with the shaggy covering, resembling an English barrister's wig.  Its gills are initially white but soon turn to pink and then black within hours.  Even if not picked they will begin digesting themselves soon after shedding their spores.  This is because they rapidly absorb moisture from the atmosphere, a trait called deliquescence.  (If you use that word in a sentence three times, you still probably won't remember it.)

Multiple ages of Inky Caps- Wikimedia

If you look closely at the top picture you will notice a ring in the middle of the stalk (stipe).  This was completely free and we entertained the kids by sliding it up and down the stipe.  This free sliding ring is an identifying characteristic as well as an indication that we have way too much time on our hands.

Common Inky Cap- Wikimedia

There are other inky cap mushrooms which are not so benign.  The common inky cap, Coprinopsis atramentaria,  is edible but only with care.  It has another common name, the tippler's bane, acquired for its tendency to produce nausea and vomiting if taken with alcohol.  It contains a chemical called coprine which blocks the enzymes which break down acetaldehyde, a metabolite of alcohol.  Acetaldehyde is the cause of a hangover.  I think by now you get the point.

By looking carefully you are unlikely to confuse it with the shaggy mane.  Its cap is smooth, tan to brown with lines or ridges radiating from the center.  The important thing is to remember which is which.  For those of us with inability to remember such details it is best to follow the rule, "Don't drinky with an inky."

Mushroomexpert.com has much more on other inky cap mushrooms.