Mushroom Forests in our Fantasy Worlds

When I showed my players the hex map I had created for our Old-School Essentials campaign, they poured over it and asked about different hexes and discussed visiting them. The mushroom forest I had placed had caught one players eye. They set out to explore the strange forest, but died to a gnoll before they got there. In Morrowind, Minecraft, and Kenshi there are giant mushrooms growing in the world and creates a strange alien landscape to explore. I personally love unusual and weird places like a mushroom forest, a black sand beach, or a salt desert. These can be memorable to your players if properly portrayed.

A mushroom forest has obvious significant differences from a typical forest, but one could argue that there are many kinds of forests that each have their own unique differences. Well yes, but Forest is an umbrella term for all of its subtypes. A jungle is one subtype of forest and when you hear forest vs jungle you think of two very different things. Now, I'm rambling about forests because when a fantasy story mentions "forest" I'm not thinking jungle or mushroom forest because we as players and referees have a general idea of what a forest is: a group of oak, pine, maple, and similar trees we see around us where we live but aren't sure of the name that covers a large area.

When I went to rural Arkansas to visit my grandparents when I was a young a vast forest was at the edge of their property. There was no fencing or barrier to separate us from the forest and it was dark between the trees. That memory has stayed with me after all these years, massive and ancient trees towering over me and barely any sunlight getting through to the forest floor. There was a windless stillness about it that made me scared to wander in. That's just a forest that adventurers stroll into while on their way to the dungeon. Now let's consider a mushroom forest.

What we need is a plausible reason that will make sense in our players heads if they ever find out why there is a mushroom forest in this part of your game world instead of a regular forest. Because this is for a fantasy setting and not hypothetical scenarios for a science textbook we won't be delving into hard science and split hairs on what mushrooms can and can't grow on. A long time ago there were tree-like mushrooms but not the large versions of the small mushrooms we see today, they looked more cylindrical. So, a mushroom is a spore producing and fruiting body of a fungus that develops from the fungus consuming nonliving organic matter. 

 What would cause a massive forest of tree sized mushrooms to grow? We can just say because the idea of a mushroom forest is cool and this is fantasy, but I find it more fun to have an actual explanation. There'd need to be a vast amount of nonliving organic matter such as rotting vegetation, animal droppings, or dead organisms that could sustain a mushroom forest for a long time. So with this in mind, I think that a mushroom forest is a short-lived phenomenon, there is a magical source feeding the fungi, or there is a steady supply of organic matter being brought into the forest to renew its supply.

Let's go with the first possibility, a short-lived phenomenon. Something caused a large amount of non-living organic matter to suddenly appear in the area. There are mushrooms in our world like the Ghoul mushrooms that grow on dead animals. What if there is a battle on the scale of the one fought at Pelennor Fields in the Lord of the Rings? Tens of thousands of casualties from humanoids to colossal behemoths now decaying along with the trees of the forest that was demolished in the fighting? Let's add that there were burial mounds under the forest that were destroyed as rotting corpses were animated and joined the battle. Now there's a large amount of nonliving organic matter for fungi to feed on and produce our mushroom forest.

The second possibility is a magical source. This is the simplest and provides the potential for tying in whatever macguffin you have in your campaign. This can include divine reasons such as a god just really wanted a mushroom forest in this area. You could even tie it in with the first possibility and have that the mushroom forest is feeding on the remains of a dead god. You can adjust how magical the mushroom are from just large mushrooms to unique types and properties in each mushroom. This would fit with, "There's a mushroom forest because I like the idea." If you don't like digging into the why, this option is probably best.

The third possibility is a source of food for the fungi is regularly renewed in this region. This could be a type of creature that migrates into the area, poops everywhere, and leaves. It could also be an infection of a spore like the fungus that takes over ants and brings the infected to the forest to be consumed. This would need to be a large number of infected to sustain the forest, but a migration of beasts might be more plausible. 

So these are three possibilities as to why there is a mushroom forest and most certainly not the only ones. I'm sure you can come up with twenty other reasons, but the main focus is that YOU understand why the forest is there. Now that we've got our explanation of what causes a mushroom forest to exist I'm going to work on my own mushroom forest and in the next post we will explore it.