Cloning Wild Mushrooms:
A Guide to Taming Nature's Fungi
Did you know?
Every single cultivated mushroom you see at the grocery store originally started as a wild mushroom, growing on a tree or in a field. At some point, someone decided to take a sample of that wild mushroom into a lab, attempting to “domesticate” it and grow it in a controlled environment. In fact, some mushrooms have been cultivated as farm crops since the 1650s—almost 400 years ago!
This blog post is a detailed account of a process we, the MushroomNerds, undertook in the fall of 2024 to tame a wild Coral Tooth Fungus.
Above is a wild Coral Tooth Fungus found in late August 2024, growing on the side of a downed birch tree. (We also found some Porcini mushrooms that day—yay!)
If you’re wondering why we don’t attempt to cultivate Porcini mushrooms, here is some background information on the types of mushrooms you might encounter while walking in nature. Mushrooms can generally be categorized into two groups: saprophytes and mycorrhizal fungi.
- Saprophytes specialize in decomposing organic matter in order to access nutrients.
- Mycorrhizal fungi, on the other hand, have a far more complex life cycle. They form symbiotic relationships with living plants, providing nutrients and hormones to the plant while receiving food in return. This interaction is mutually beneficial.
Due to their intricate relationships and life cycle, mycorrhizal fungis’ life cycles have proven extremely difficult to replicate under controlled, cultivated conditions.
With that background, let’s focus on the Coral Tooth Fungus. Its appearance and habits makes it easy to recognize as a close relative of the Lion’s Mane mushroom. It has a similar overall growth habit and shape, but the spines of the Coral Tooth are less densely packed and more branched, giving it a distinct, coral-like appearance. In my opinion, the flavor is more intense (and better!) than Lion’s Mane, and I appreciate that it doesn’t absorb as much liquid when cooked.
In order to tame a wild mushroom, modern mycology typically relies on cloning. Mushroom cloning is a relatively simple procedure that involves taking a tissue sample from a mushroom and propagating it under controlled culture conditions. It is analogous to taking a cutting from a plant to grow a whole new one.
In this case, we brought the Coral Tooth Fungus into the lab and split it open to reveal the clean (or mostly clean) interior tissue. Using a sterile blade, we carefully cut out a small piece of this tissue and placed it directly onto a nutrient agar plate. This gives the fungus an opportunity to grow quickly, but it also allows any potential contaminants to flourish. Common contaminants include molds, bacteria, yeasts, and occasionally bugs, all of which can turn your efforts into a messy failure. That is why it is critical to start with the healthiest cleanest mushroom you can find.
The nutrient agar plate we used contains yeast peptone dextrose, a rich medium commonly used for growing fungi. At this stage, we didn’t include antibiotics, though doing so could be helpful for preventing bacterial contamination in the initial cultures.
Once you observe fungal growth from your excised tissue, you’ll likely need to passage it one or more times in order to obtain a pure culture. This is because the initial culture may contain contaminants such as yeasts, other fungi, or bacteria.
To separate the fungus from these contaminants, carefully cut a small piece of healthy, growing fungal tissue from the growing edge of your fungal culture and transfer that to a new agar plate. Repeat this process, transferring small pieces of clean tissue to fresh plates, until you achieve a culture that appears free of contamination. For good measure, perform one additional transfer to ensure purity.
Left and right: Growing excised tissue and tissue isolated from Plate #1. In this case, we were fortunate—there was no obvious contamination at either stage. This is uncommon when working with wild-foraged mushrooms introduced into culture conditions.
After several passages, and allow the agar culture to grow for an exteneded period, you can clearly see that the cultured mycelium is beginning to take on the characteristic shapes of Coral Tooth Fungus. This was all the confirmation we needed to be certain that our cloning efforts were successful!
The final step in this process is to expand the culture and attempt fruiting.
In this case, the fruiting conditions for Coral Tooth Fungus are similar to those used for Lion’s Mane. We expanded the cloned tissue from the agar plates into sterilized sawdust spawn, following the same method we use for growing Lion’s Mane. Once the sawdust spawn was fully colonized, we initiated fruiting under conditions of 90% humidity and a temperature of 15°C (59°F).
Check out the results below:
Overall, the process took about two and a half months to go from a foraged wild mushroom to a cloned and cultivated Coral Tooth Fungus. While Coral Tooth spawn is commercially available from other sources, we chose to work with a local variety to produce something better adapted to the Atlantic region of Canada. We will be expanding this for outdoor growth in the MushroomNerds garden for next season!
A similar approach can easily be applied using store-bought Oyster mushrooms. With Oyster mushrooms, sterile techniques are less critical as they grow extremely fast, making them an excellent first project for aspiring mushroom culturists.
