After the first significant rains of fall, the fungal world awakes from its summer slumber and swells to abundance. Enter the wide world of mushrooms and fungi in general are everywhere even on your lawn. Imagine a world without fungi, it would be very different! Leaves would not decay, a layer of dead flora and fauna would build so thick you would be walking on ground hundreds of miles deep, in rotted leaves, bugs and dead stuff, nothing would rot. Doctor Carl Linnaeus in 1735 organized the natural world into a system of classifications beginning with only three ‘kingdoms’ mushrooms and fungi were grouped with ‘plants’ in his organization of taxonomy. Science today suggests another kingdom, that of fungi in general. So prevalent in our world and so diverse is the world of fungus it boggles the mind. Fungi are often referred to as the ‘Fifth’ kingdom.
Your first steps in un-boggling your understanding of mushrooms is to take some baby steps. Pick a mushroom or better still, pick a mushroom out of the bin at the grocery store, pick two, one that has a ragged membrane under the cap that has been partially broken, make sure it retains some of its stem, not cut close to the cap. Then pick one from the brown bin with the membrane unopened, so long as you have one of each. These mushrooms are grown year around in a very controlled environment in a sterilized medium, this to prevent uncontrolled spores invading the mushroom beds, like a poisonous mushroom growing among the edibles, not good.
When you get home lay the two mushrooms on a bit of white paper. Be sure to have a notebook to write down your observations, a small magnifying lens may help. Step one, observe the outside features; it has a cap that is rounded, your mushrooms may be mostly white or a soft brown color depending on which bin you chose. Observe the stem, it is thick compared to the cap. The base of the stem has been cut off during harvest or you might see the thready roots of the mushroom host. Now turn the mushroom on its cap, stem up. The underside of one has a ragged veil that reveals the gills under the cap, as the mushroom grows this veil tears open and exposes the gills under the cap. Your second sample has not yet ruptured, study the texture and note the delicate, thin skin it is made of. Carefully remove the veil with the tip of your pencil and hold it in your hand, the veil is so fine you may not be able to actually ‘feel’ it. In some mushrooms the veil leaves a little ‘skirt’ on the stem, in some there is a ‘ring’ on the stem before the veil breaks. This membrane keeps the spore ‘seeds’ of the mushroom from falling too soon. Now snap off the stem of one of your samples, observe the gills, their color, do they attach to the cap and the stem or not. Do the gills line up one by one or do they have a short one, long one, short one pattern? Note how the stem attached to the cap you have broken off, some mushrooms break cleanly at the cap. Study the broken stem by cutting it lengthwise, observe the interior of the stem, is it hollow? Some stems are filled with a ‘jelly’ and some break smoothly, some are woody with long strands and squish when you try to break them. Note your observations. Now cut the cap in half and look at the gills, note their color and texture. Using a finger or a pair of tweezers remove one of the gills. Using the magnifying lens to look closely at the gill, you are looking at the reproductive base of this mushroom. The spore are tiny little seeds, shaped like a grain of rice. Most are not visible to the naked eye and need to be sectioned, stained and looked at under the microscope.
For now, remove both stems and put the caps, gills down, on white paper. Leave them overnight undisturbed. After the membrane is torn the spores begin to dry out and fall off the gills. In the morning carefully lift the cap straight up without dragging it on the paper. Observe the spore prints, you should see an impression that looks like the gills but flat. Be very careful not to breath on the spore print or try to wipe it off, it is very fragile. Each gill has dropped a fine line of spores overnight. Note their color, this is a very important clue to identifying your mushroom. If you have chosen, the regular ‘white’ mushroom and a brown one from the bin marked “Bella or Portobello” each will have a different spore print. If you have access to a microscope you will note that both gills, the brown one and the white one, have identical spore arrangement, they are paired, or bi-sporeous. Under the microscope they look the same but for their color. Think about dogs, specifically the Labrador retriever, a large dog very common as a family pet. Labs come in brown, black and the most common blonde or ‘yellow’. They are the same ‘species’ as are your mushrooms. Now log into the ‘Net and search for Mykoweb, here is a comprehensive text on mushroom identification and properties. First look for the family, yours is Agaricae and then work through the physical characteristics from your notes. Once found the site will offer a text that can be scientific at times and hard to understand. There are excellent pictures to compare to your samples and notes on edibility, toxin and other cautions. The clues in this text will help guide you to the right name for your mushrooms. The problem is, there are lots of variations, some deadly poisonous, some inedible with numerous ‘look-alikes’. The lesson here is, stick to eating grocery store mushrooms that are carefully grown. Study the many kinds of mushrooms out there using the same methods to narrow down the trail to positive identification. Always keep in mind, IF IN DOUBT THROW IT OUT! Happy hunting.
Bill Hanson is a Sonoma County native and a lifelong sportsman. He is the former president of the Sonoma County Mycological Association. Look for his column in The Community Voice each week.