This quick update will cover our recent project with Dr. Rytas Vilgalys, Professor of Biology at Duke University. Dr. Rytas was kind enough to do some PCR DNA and get an ITS sequence of some of our various collections of Pleurotus that were found growing on pine wood.

Over the past 2 years, James and I have been on the hunt for an oyster mushroom that grows on pine. To explain, I should first give a little background about these particular fungi. They tend to favor deciduous wood, especially poplar trees in Colorado. To most fungi, pine wood isn’t something easy to eat. Coniferous trees contain natural resins that tend to contain chemicals that are quite anti-fungal. This does not mean that fungi cannot eat coniferous wood, it is just quite difficult for them to do. However, Pleurotus are special fungi. They have discovered a quite efficient method of decomposing their substrate, excreting powerful digestive enzymes able to breakdown many different types of freshly cut wood. There is even a type of Pleurotus that can grow on cactus skeletons! The Pleurotus that James and I had found were growing from the cut stumps of pine trees and a spruce log growing at 10,000′ in elevation. These were cultured in our lab in Denver and were eventually sent to Dr. Rytas. He was interested in them because of their unique habitats they were found growing in and was wondering, as we were, if they were a possible new species of Pleurotus. He also received a few control collections of Pleurotus pulmonarius from various locations in the state, growing from cottonwood trees. These were tested against the mushrooms that were found growing on conifers. This testing is basically done by taking known sets of genes from a specific species of fungi and testing samples of DNA against those genes to see if they are similar enough to be the same genetic group (hopefully that wasn’t too over simplified?). Much to our surprise, every specimen came back as P. pulmonarius! It is well documented that P. pulmonarius grows occasionally from conifer, but these specimens also had unique morphological features that were distinctly different, even with indoor grown mushrooms in a controlled environment! Just goes to show that morphology sometimes can tell you very little about what type of fungi you have. We now know that our cultures of oysters collected from these conifer habitats are P. pulmonarius, but have somehow developed a unique set of digestive enzymes to deal with the oils in the wood that tend to inhibit fungi.

The reason James and I are extremely interested in pine loving oysters is because the Rocky Mountains are plagued with a pine eating beetle that is destroying our forests by the entire mountainside. The general way to deal with this problem (due to the extreme fire danger it creates) is to cut down the infected trees and pile them in large piles. They are used mainly for fire wood, but the pine loving  mushrooms would decompose the wood much faster, creating larger soil depth. Paul Stamets has a discussion in his book, Mycelium Running, about the honey mushroom and its method of creating a deeper humus depth. Many of these plagues, whether they be a fungus or an insect, may look very disastrous to the environment to humans. This is only because of our perception of time. The trees that once stood as a forest are now decomposing, increasing the potential of the forest to create more life. As soil depth increases, the forest can house more and more plants. We would like to make these Pleurotus part of the solution to this large problem we are facing today.

The guys over at Kauai Fungi were kind enough to donate 2 petri dishes of Pleurotus djamor, the Pink Oyster Mushroom, to us here at Amateur Mycology for the Amateur Mycology Culture Library. Saturday they arrived in the mail! We quickly made sure they were not sitting in the mail box too long, as it is still very cold here in Colorado, and Pleurotus djamor is known to have mycelial die-back if temperatures go below 60 degrees F. This also brings up the question as to how you keep these tropical mushrooms in cold storage. We will ask Kauai Fungi this week and give you all an update.

If you look at the picture above, you will see a close up of the mycelial growth of the Pink Oyster, which to our surprise, was bright pink!! Dana said it looks like Pepto, and I would have to entirely agree. Interestingly, when I took pieces of it out in the laboratory and transfered them into test tubes, I noticed that it stains the agar that same bright pink! What an interesting fungi.

Now for those of you who do not know what this mushroom is for, James and I went to the Denver Botanic Gardens and spoke to the curator of the tropical plants at the gardens, who is in charge of the plants inside the glass conservatory/ atrium that houses most of the tropical plant specimens. He voiced interest in growing fungi inside this tropical environment, and James and I jumped on the project the first chance we got. When we met and talked about the project, and he explained how he would like tropical species of mushrooms if they were to be displayed inside the conservatory, and lucky for us we already had connections to Kauai Fungi in Hawaii. Despite his enthusiastic response to the idea, the Pink Oyster will not be displayed inside the DBG’s conservatory using our techniques. However, we have other botanic gardens who are interested. We are also developing other species of mushroom for display, but more research is needed.  Check back soon for more information!

While driving through Littleton, Colorado James and I came across a park that had many different species of mushrooms growing in it. What first got our attention was large fruiting of Agaricus in the area, and as we were working on the Colorado Agaricus Project, this park was an interesting find. Unfortunately for us, most of the Agaricus found in the area were the yellow staining, foul smelling and poisonous Agaricus xanthodermus (the bane of most Agaricus hunter’s existence) and the giant mushroom of culinary disappointment, Agaricus bernardii. However, in one corner of the park, a cottonwood stump had been chopped to just above ground level. This stump had Oyster Mushrooms (Pleurotus pulmonarius) growing out one side, and Velvet Foot Mushrooms (Flammulina velutipes) out the other! Luckily for the Amateur Mycologists, we are able to culture these fungi in sterile lab conditions, as well as establishing them on cardboard for a more ‘natural’ form of storing the mycelium, making them the newest members of the Amateur Mycology Culture Library. Remember… the Amateur Mycology Culture Library page has an updated list of species in cold storage, and make sure you check back soon to see a full explanation of cardboard/stembutt culture from the exact oyster mushroom cluster pictured above!

James and I have been spending the past 3 months amassing mushroom species in pure culture and putting them under cold storage. You might be thinking, “what the heck is he talking about?”. To explain a little more clearly, we are ‘cloning’ wild mushrooms. This process is done by extracting flesh or spores from mushrooms that we have collected in the wild, and growing them in petri dish or test tube on different types of ‘media’. This media gives them nutrients specific to the species of fungi we are trying to grow. Now, when we talk about growing mushrooms, you first must isolate the part of the fungus that produces the mushrooms. Mycelium is a network of hyphae, or chains of cells, that are able to uptake water and various nutrients, as well as excrete digestive enzymes to digest it’s food, which in turn produces the mushroom. The mushroom is actually the fruiting body or sexual reproductive organ of the mycelium that produces spores to grow more mycelial networks. Under cold storage (i.e. 38 degrees F) the mushroom mycelium’s growth slows to a crawl. This allows the cultivator to store the mycelium until it is ready to use. To see a complete list of the different species we have go to The Amateur Mycology Culture Library page. We update it regularly.

Clitocybe nuda, otherwise known as the wood blewit or the bluefoot mushroom, is fairly rare here in Colorado favoring more temperate climates of Europe and North America. This week we found quite a few of them in Denver. It was amazing to see a fairy ring 30′ in diameter fruiting these beautiful purple mushrooms, and the best part is they are edible! The French, the Dutch, and the English cultivate it for export all over the world. In fact, just recently I was in Whole Foods and noticed they had bluefoots imported from France. The good news is we also have this mushroom as a part of the Amateur Mycology Culture Library, and is destined to be an integral part to our mycoagriculture projects next year! I tried cooking some of the ones I found in Denver in a stir fry this evening and they were absolutely amazing. They also kept their wonderful purple color, which gave wonderful contrast with red bell peppers and snap peas. Delicious!

While working in The Amateur Mycology Lab this week, we noticed something very interesting: our contaminated petri dishes that we had attempted to clone a turkey tail mushroom (Tramates versicolor) had begun to crawl across the areas with bacterial contamination! Not only that, but it seems that the mycelium is favoring areas where the bacteria has set up shop. Fungi never cease to amaze me!