'We are advancing the science': Wild mushrooms, DNA and citizen scientists in Colorado's Mountains
Rain in the forests of Colorado brings the promise of wild mushrooms. It’s a beacon summoning a seasonal army of mushroom hunters to the Rocky Mountains.
A recent drenching lured a group of foragers out of their homes on a Wednesday morning in late August, to a spot at 9,000 feet, just outside of Colorado Springs.
James Chelin led the group of about a dozen on this wild mushroom foray. He’s a computer guy by day. But in his spare time, he’s the vice president of the Pike’s Peak Mycological Society, and he regularly takes groups of the curious and the dedicated up winding, often unpaved mountain roads, to teach them how to find — and identify — wild mushrooms.
“It’s still pretty wet. We have a lot of eyes on the ground, we’ll find stuff,” Chelin said, admiring the moist conditions on the forest floor. “I've been coming here for over 15 years, and I always call it my 9,000-foot spot. We’ve found chanterelles over on this side.”
Mushroom enthusiasts get excited about chanterelles, hawks wings, oysters, king boletes — anything that makes a tasty meal. But for Chelin and many of the foragers who came along for this trip, those delicacies are an aside. “What we're doing here, is that we are advancing the science,” Chelin explained. “And if we find something to eat, that's a bonus.”
The citizen scientist and the yellow russula
Alan Rockefeller came along as a special guest. He is a self-taught independent mycologist who has become a highly-regarded expert, traveling the world to identify, describe and analyze the DNA of wild mushrooms. The Pike’s Peak Mycological Society asked him to join the foray so he could lend his expertise to help the group identify all of the specimens they’ve turned up this year.
A bright yellow mushroom — a type of russula — stopped him in his tracks. “This looks like the one I was finding in Arizona that smells strongly like bananas when it dries,” he said. “I’m pretty sure it's a new species.”
Rockefeller has been chasing this yet-unnamed banana-scented russula from Mexico to Canada. He’s seen it as far south as Michoacan and all the way up in British Columbia. But he’s also excited to find it here in Colorado, because that means he can add pieces to the sprawling and incomplete puzzle that is mushroom knowledge.
“’The mushrooms don't get anywhere randomly,” he explained. “They're associated with the same tree, or they got carried by an animal.” Every discovery helps to paint a more complete picture of the mycological map. “Once you have enough points on the map, you can start to figure out a little bit more about what it's doing and the ecology.”
Rockefeller travels with his own portable laboratory so he can prep mushroom samples for DNA sequencing wherever he is — whether that’s a rainforest in South America or a friend’s kitchen table in suburban Colorado. His plan is to send a sample of this yellow russula off to a lab in New Jersey. The DNA sequence he gets back will help him prove the ecological connection between Colorado and other locations where he’s found this particular mushroom. Eventually, he will share all his information with other mycologists online, and everyone will gain a deeper understanding of the new species.
New is everywhere
But the yellow russula is only the beginning.
It is surprisingly common for new mushroom species to turn up in Colorado during a good monsoon season. During his time in Colorado, Rockefeller spotted novel species everywhere. “I think we found more new species than we have found species that have names,” he said.
The key skills needed for this particular hunt are curiosity and a discerning eye. “It's probably accurate to say that every time you walk through the woods, or every time your follow citizen scientists through the woods, they're going to notice a lot of new species, if they’re paying attention.
Of course, “new species” in this context does not necessarily mean that it’s rare. “It means that it hasn't been described yet,” Rockefeller explained. He has seen that yellow russula dozens of times. “But the scientists don't have a name for it yet,” he said, and no one has made the geographic connections that he’s working on now.
Andrew Wilson, the associate curator of mycology at Denver Botanic Gardens, says there's a lot of mushrooms that aren’t fully understood by scientists. A good monsoon season can conjure up a host of unfamiliar species. In particular, “these last two seasons have been exceptional,” he said. “There's been quite a bit of diversity coming up with all the rains.”
In fact, Wilson has seen so many new mushroom species cross his desk this year that he struggled to recall any particular one to highlight. “Sometimes they all become a blur,” he said.
Gap in the science
According to Wilson, there is still a lot of work to be done on basic mushroom taxonomy. Wilson pins it on human bias. “We tend to observe and recognize what we see,” he said. “It's just easier to study plants and … we relate to animals more easily.”
Fungi, on the other hand, are difficult to observe: the main body of a fungus is the mycelium — underground root-like structures that aren’t obvious to the casual observer. “Fungi are hidden from view,” Wilson explained. “They're all around us all the time, and we don't even know they're there. They're doing important things behind the scenes.”
The mushrooms that attract so much attention are just the reproductive fruit of the larger fungal organism: like apples on an apple tree. Fruit may come and goes with the season, but the tree is always there. Except when it comes to mushrooms, the main tree is the mycelium — which is all underground. “The challenge for us as human beings is, because these processes and these organisms are so cryptic and so hidden from our view, it's a challenge to try to understand what they're doing,” Wilson said.
And when those mushrooms are in season, even experts can have a hard time telling them apart. “We have a lot of different species that just look alike, and we might lump them into one same species group because they're morphologically similar,” Wilson said. But then scientists started taking a closer look at the genetics of all those mushrooms — including DNA analysis, and they realized looks can be deceiving. “we're seeing that there's a lot of genetic differences between all of these mushrooms that look identical to us,” Wilson said.
For all of those reasons, the science is still developing. That creates an opportunity for citizen scientists to fill the void. Wilson says the vast majority of the mushroom specimens in the Denver Botanic Garden’s own collection were found by amateur citizen scientists.
But even when the amateur enthusiasts do step up with the goods, the science of mushrooms lags far behind the fieldwork. And that’s because finding a new species is easy compared to the laborious process of documenting them in the scientific literature.
“There's likely lots of new species in Colorado,” Wilson said. “The process of describing is really complex. We're talking about a couple of years worth of work to get the data and do all the proper vetting. So it's not that common to describe new species because of the work involved.”
Increasingly accessible science
But as technology advances, citizen scientists are becoming increasingly capable of doing the hard work of filling out the scientific literature outside of the scientific institutions. “The capacity for the average everyday person to create a DNA laboratory in their garage has grown significantly,” Wilson said. “The capacity for somebody to take these organisms, remove their DNA and amplify the regions of the DNA that help us distinguish one species from another is accessible. If you're willing to pursue it.”