4 – Fascination of Fungi
Want to know the fastest way to upset a fungi fan? By referring to mushrooms as vegetables!
We get asked a lot how we got interested in farming mushrooms in the first place. Fair question, since none of us had a prior background directly linked to mushrooms. We’ve got a lot of reasons, but firstly, we full-heartedly believe that there is a lucrative market in mushroom production, urban agriculture, and many other niche uses of fungi (biodegradable materials/packaging, bioremediation, even fashion!), but more importantly, we just find mushrooms and fungi to be quite fascinating!
Now this might be grade school review for some of you reading this blog, but let’s start off easy: we cultivate mushrooms, but mushrooms are just the “fruiting body” (part that allows for spore propagation) of the entire organism known as the fungus. Fungi actually represent a completely different kingdom of life than plants or animals. At the cellular scale, fungi are eukaryotic organisms (meaning they have a nucleus housing the DNA), but since they don’t have a cellulose-based cell wall or chloroplasts, they are set apart from plants. In fact, fungi are more closely related to animals, and at one point shared a common ancestor about 1 billion years ago. (Source)
A billion years is a lot of time. I often like to think about how specialized animals have become during that time frame: we’ve developed vertebrates, mastered the oceans and land, grew to massive sizes, and one species in particular learned how to build AI computers that are capable of brewing the perfect beer (https://vimeo.com/172395607). But while fungi haven’t yet learned how to develop AI, it would also be naive to think that they haven’t been specializing in other ways during that billion.
The surprising thing, and possibly why they are still so fascinating, is that we still know very little about some of these “specializations.” Mycologists are just starting to scratch the surface on how exactly these organisms live and their role in maintaining natural ecosystems. I’ve already mentioned the “fruiting body” or “mushroom” as one of the fungal structures, but one of the others that many people overlook is the mycelium. Mycelium is the fine, web-like vegetative structure that secretes enzymes into materials or substrates, thereby breaking down the original material (usually biological, but some can dissolve rocks! (Source) and allowing the fungus to absorb essential nutrients. The mycelium structure can be microscopic, but there are also species that can grow to over several square kilometers in size. In many ecosystems, the vast mycelium networks also play a role in connecting different species and creating symbiotic relationships between them. This is as simple as decomposing dead material and making nutrients more bioavailable for plants and animals, but at the same time, new studies show that the mycelium network within forests can act as a communication network. Trees and other organisms that are tapped into this fungal network can share nutrients, and may even communicate, learn and remember (Source)
So why don’t we know as much about fungi as we do plants or animals? Plenty of reasons, but two simple ones are: 1) the study of animals can help understand our own species, and 2) plants are easier to find than fungi. The first reason is quite intuitive, and I don’t think it requires a full explanation. However, those mycelial structures that I mentioned above are often overlooked because they are often underground or growing within another organism. That means that often the most prominent feature of some fungi is the fruiting body – a small structure that only periodically makes a several day appearance before self-decomposing. If you’ve ever seen a mycologist go crazy with excitement upon stumbling across a rare species, it’s exactly because they can be so difficult to find. This difficulty in finding them is a huge barrier when conducting studies, and it’s only made more difficult since many species can’t yet be grown in lab-like settings.
Luckily for us, some species are easier to grow in artificial conditions than others. The species that we cultivate are largely oyster mushrooms (Pleurotus ostreatus), king oyster (Pleurotus Eryngii), and shiitake (Lentinula edodes), but we are also experimenting with other varieties such as Lions-Mane (Hericium erinaceus). These species are all wood saprotrophs – a term that means they break down woody materials (in particular lignin and cellulose) to meet their nutritional demand. We use plant-based organic material, such as wood chips, straw for the substrate, but one thing that we find really inspiring is that we benefit from using urban waste streams from cafes and breweries since lignin and cellulose can be found in coffee grounds and beer grains. It’s really amazing to watch how fast the mycelium colonizes the substrate, as the fungi absorbs as many nutrients as possible before getting ready to produce the mushrooms.
There’s so much to write and talk about when it comes to fungi, and we will definitely write more in-depth blog posts as we continue to learn, especially about the science behind our substrate mixtures and some of the other possibilities such as biodegradable materials, bioremediation, and health benefits that fungi may help us achieve.
We are really excited by what we’ve learned so far, and are really eager to keep discovering more about this fascinating life form!