Mushroom Aging

Though official mushroom spring is coming to an end, the forest floor is still covered in mushrooms. On a walk with a fellow forest land steward recently, we were identifying a verity of fungi in her woodlands and began a discussion on aging a mushroom. We saw a string of Helvella lacunosa at different states of decomposition in a row. For a moment, my friend thought they were different kinds, because the aging had turned the older mushroom into a completely different color and texture. It left me wondering how many people are often confused by this transformation, and think there are several different kinds of mushroom, when really, it’s just slow decomposition causing chemical change.

I’ve taken a series of photos here all at the same time in the same area of EEC forest. Clitocybe is an excellent type of mushroom to observe in this exercise, as it tends to bloom in the same area at different times, is a common woodland fungi, and has very diverse stages of decomposition. This genus of mushroom is in the family Tricholomataceae of the order Agaricales (gilled mushrooms). These are important steps to identifying the fungi you’re curious about. Even with photos and many good references to compare to, my guess at Clitocybe could still be wrong. My second guess would be Tricholoma, but the gills do run down the stem.

As the mushroom ages, its cap edges begin to turn upward, and the whole mushroom starts to darken. Color is not the best way to identify mushroom age, unless you know the species right off the bat. It’s also a very good idea to confirm you are looking at the same species throughout your observations. Because of the common habitat shared by many mushrooms, you’ll often see a verity of species in one area. Even in the pictures of this study, there are other species in the background. Often, the size of a mushroom continues to expand, but it will also usually be melting at the same time, as seen in the picture below.

The flesh of a mushroom is the best way to judge mushroom age- as they become softer/slimier as they begin to decompose. This is due to the high water content of the fungi. Not all mushrooms melt, but in the order Agaricales, all fleshy gilled mushrooms decompose from solid into liquid. They usually turn darker with age, and in this study, the changes are clear. You’ll not always have the chance to see the same mushroom at different stages as you walk through the woods, but if you have an eye on one at the edge of your walk to the car, or from your seat on the porch, take a few days to track the fungi as it grows. The excitement of watching a mushroom evolve is a great journey in nature’s cycle of life.

One more note on aging- sometimes, a mushroom has been predated upon, or shredded by wildlife moving through on a trail. The picture above shows this damage, which is not directly related to the aging process. The flesh on the fungi above is still relatively firm, though the color is darkening. These mushrooms are not melting, but tattered from a battering. You also see slugs, flies, and larva munching on mushrooms, and hastening their demise. Some mushrooms will bruise when touched, and that marking can aid in aging a mushroom too.

The identification adventure in mycology can become very frustrating, but the more time you spend observing mushrooms, the more familiar they become. It helps to follow through with keying out your species, so take that next step when you leave the field and pick up a field guide or spend some time browsing images on the web. The internet is no sure bet, but you can get ideas there, and broaden your search. By keying out your mushroom, you may not get an exact match, but you’ll have some idea of order or family. This is sometimes as far as you may go- and that’s ok, it’s learning!