By Dr. David Wartinbee, for the Redoubt Reporter
For the past couple weeks I have been discussing how forest fires can negatively impact stream ecosystems. There are, however, a number of positive things that we can look forward to after a major fire. Given enough time, the original plant community will return, along with the various species of animals the habitat supported previous to the fire.
As the various plants become re-established and start growing, young trees are just the right height for hungry moose. Think about the limited number of birch, willow, aspen and cottonwood limbs that moose can reach in a mature stand of trees. But if all the trees are only a few feet tall, the moose are well-fed. Several years after a fire, there tends to be an increase in the number of moose the forest can support. This increased moose population may be maintained for 20 years as the forest recovers.
Another of those positive things humans can look forward to after a forest fire is an increase in the abundance of prized morel mushrooms in the burned areas. For some reason, morels seem to flourish in areas for a couple years after a fire.
After a huge fire in Tok in 1990, there were so many morels appearing that hundreds of people gathered mushrooms by the five-gallon bucketful and sold them for about $5 a pound. Some were shipped out fresh while others were dried for later sale. Today, dried morel mushrooms command well over $100 per pound.
An obvious question is, why do morels appear after a fire or forest disturbance? First, we have to understand the basic life cycle of mushrooms before a likely answer makes sense. Mushrooms are the fruiting body of a fungus and they release millions upon millions of spores into the atmosphere. Puffballs are fruiting bodies of another fungus and that brown “smoke” that is released when you kick them is actually millions of spores being ejected into the air.
The spores travel for many miles in the air. Once they reach the ground, they germinate and form hyphae or mycelia. These ultrafine masses of long, branching hyphae invade the soil and grow over wide areas. At some point, and under the stimulation of some unknown series of conditions, chemicals or disturbances, two sets of hyphae join together to form a different set of hyphae. These different hyphae are the ones that grow rapidly and form the fruiting body we call a mushroom.
The mushroom produces its spores and the process starts all over again. Morel hyphae may remain in the soil for decades before they produce a mushroom.
It is thought that many morel hyphae work with various plant roots symbiotically as mycorrhizae. Many plants rely upon mycorrhizal fungi to help them acquire nutrients and water from the soil while the plant provides something for the fungal hyphae, like sugars or other nutrients.
Mycorrhizal associations are well recognized for many plants and many appear to be obligatory for the survival of both organisms. It has been suggested that after a fire destroys many of the plants the morel hyphae may have been working with, the hyphae are stimulated to form fruiting bodies and send their spores far and wide in hope that some will land in areas with living plant roots.
Morel mushrooms do not always need to have a fire in order to produce fruiting bodies. Morels specifically seem to form fruiting bodies in late May and most of June. However, since they tend to do so randomly, the mushrooms can be widely scattered in conifer or deciduous woods.
Many of our local mushroom hunters have been concentrating their efforts looking for morels in and around areas affected by our many different fires in recent years.
This past weekend my wife and I were out prospecting in a burn area. We found a few early morels. It is still a little early and in the weeks to come there ought to be many more popping up. We had them for dinner and I can only tell you that they were simply delicious.
Fortunately, morel mushrooms are quite distinctive and there are only a few distasteful ones to confuse the amateur. I would suggest joining the Kenai Peninsula Mycological Society. They are a group of friendly mushroom enthusiasts and there are a number of real experts who can help you learn which mushrooms to try and which ones to avoid.
They can be reached at http://www.groups.google.com/group/kpms.
David Wartinbee, Ph.D, J.D., is a biology professor at Kenai Peninsula College’s Kenai River Campus. He is writing a series of columns on the ecology of the Kenai River watershed.