Morel mushrooms. We’ve had our first spring rainfall, and they may now be popping up in the woods as you read this. Or, they may not be. If you’ve ever hunted or eaten them, you probably feel the itch to get out and find the delectable fungi -- and you likely also know how elusive they can be.
This is partly why the yellow morel mushroom, orMorchella esculentoides, is so sought-after, with one pound often fetching as much as $25 when sold commercially. Under the best conditions, you might find a barrel full under one tree, or you might look for hours and come up empty-handed. So far, no one has figured out how to reliably cultivate them.
Considering this elusiveness, we became curious: how will last August’s derecho in Cedar Rapids affect the number of morels we’ll find this spring? They typically pop up in abundance under dead elm trees, and if there’s one thing we have plenty of this year, it’s dead trees. Does this mean we’ll find more mushrooms?
In true morel style, there’s not an easy answer. They’re a bit more complex than your average fungus. To gain some insight, we need to explore a bit about how morels grow.
Some species of fungi feed on dead organic matter, like logs, trees, and leaf litter. Think of the common (and delicious) oyster mushroom. You will always find it on a tree or log. These kinds of fungi aresaprotrophic.
Other species live in a kind of symbiotic relationship with plants or trees. The trees provide sugar and starches to the fungal mycelium (the long, white, threadlike part of the fungus that lives in the soil and tree roots), and in turn, the mycelium help bring water and nutrients to the tree. These kinds of fungi aremycorrhizal (my-kor-EYE-zuhl).
Cool stuff, right? But how does this apply to morels?
Part of what makes morels so mysterious is that scientists haven’t figured out if they’re truly saprophytic or mycorrhizal. Many believe that they vary between both, at different stages in their life cycle. Consider again how in Iowa, morels grow in abundance under dead elm trees. Typically, in a mycorrhizal relationship, the tree needs to be alive in order to share resources with the fungi. So the morels may simply be saprophytic and feeding on the dead tree roots.
However, there is an astounding tendency of fungi in mycorrhizal networks to send up their ‘fruiting bodies,’ or mushrooms, when the ‘host’ tree endures some sort of trauma. Mushrooms are, after all, only a small part of the entire fungus, whose purpose is to spread spores. So it stands to reason that if its source of food is threatened, the fungus wants to find a new host tree, so out pop the mushrooms to disperse the spores as a kind of last hurrah. This could certainly explain why morels are found under dead elms.
In either scenario, it seems that the damage the derecho caused would lead to increased fruiting of mushrooms. But there are still many additional considerations.
Ideal Morel Conditions
Morels need just the right conditions to grow in a typical spring: soil temps of 50-60 degrees, air temps in the 60s during the day and 40s at night, moist loamy soil, and proximity to dead American Elms (but not TOO dead!) or certain other hardwood trees, for starters.
And then, even if all conditions are perfect, you may still strike out.
Luckily, we have a few other clues that suggest the derecho will lead to a greater quantity of morels if the necessary conditions are met -- if not this year, then in the coming years.
Some avid morel hunters seek out major logging areas. There are many stories of hunters finding the mother lode of morels downwind of logging sites. Additionally, black morel hunters in Colorado and other western areas find an abundance of morels in areas cleared by wildfire. In both cases, it can take up to a year after the event for the morels to show up, but the disturbance is creating ideal conditions for the finicky fungi to grow. In general, we know that morels like disturbed soil.
The derecho definitely disturbed things. It blew the foliage and limbs off many elms and other hardwoods, stressing the tree, almost certainly affecting their mycorrhizal fungi networks. It killed many trees, providing more food for saprotrophic fungi that feed on dead organic matter. And if nothing else, the falling limbs and blowing debris disturbed the soil, potentially creating more ideal ground conditions for the fungi to flourish.
In lieu of actual scientific studies, the best we can do is hypothesize, and then see what happens. With any luck, and a little more rain, perhaps an abundance of these tasty delicacies will provide a welcomed silver lining to Cedar Rapids’ latest climate disaster.
Fun fungi fact:
You may have heard in recent years about incredible discoveries regarding how mycorrhizal networks connect entire forests, resembling a brain or nervous system, sharing information and resources between trees and plants. For example, a dying tree sends its carbon into its roots, and the fungal mycelium share it with neighboring trees -- even those of other species. Healthy, established trees have been shown to share resources with up to 45 other trees through its mycorrhizal network, ensuring the survival of the seedlings. In fact, scientists now believe that forests as we know them couldn’t exist without these fungi networks.