Identifying mushrooms just isn’t as easy as matching the mushroom to a picture in a book. Photo: Emelie Swackhamer
There are a few distinctive mushrooms, but even those that seem like they should be easy to identify can be confused with dangerous look-alikes. For example, the giant puffball, Calvatia gigantea, grows to be a very large, distinctive "mushroom." However, when they are still small and just starting to form they can look exactly like the young, developing and quite poisonous Amanita.
Experts who identify mushrooms certainly do take the color, size and general appearance into account. What people do not realize is that more information is needed to accurately and confidently identify a mushroom. One needs to carefully examine structural characteristics:
- Does the mushroom have gills or pores?
- Is a veil present or absent around the stem?
- Are gills attached to the stem or free?
- It also helps to know if the mushroom is growing in association with specific plants; in a lawn, on rotting logs, mulch etc.
There are several other tests commonly used to gather important clues. Spore prints are made by placing the cap of a mushroom on paper and leaving it sit overnight. The tiny spores fall out of the mushrooms onto the paper and en masse they are a distinctive color. A solution of potassium hydroxide provides another useful test because it will produce a predictable color when placed onto some mushrooms. Microscopic examination is used to determine spore shapes and other cellular characteristics. True experts might use even more tests to be sure of a mushroom's identity.
It is really important to not be over confident when trying to identify mushrooms. Some mushrooms are very poisonous. It is always best to enjoy looking at wild mushrooms, but only eat mushrooms that you purchase from a reputable mushroom grower through a grocery or market.
One additional caution: Some people are even sensitive to the mushrooms that most people consider safe to eat. If you have never tried a certain kind of cultivated mushroom that you purchase, try just a tiny bit first to make sure you do not have sensitivity to it.
A mature size large giant puffball (Calvatia gigantea). Photo: Emelie Swackhamer