Subterranean Mushroom Farming for Pros

Edible Geography has an excellent post on the Li-Sun Exotic Mushroom Farm in Australia, which can serve as a good start to investigating what a large underground food production operation looks like.

Logistics: Li-Sun grows at least eight varieties of edible mushroom, and several varieties of medicinal mushrooms as well.

The tunnel for which these mushrooms have been so carefully developed is 650 metres long and about 30 metres deep. Buried under solid rock and deprived of the New South Wales sunshine, the temperature holds at a steady 15º Celsius. The fluorescent lights flick on at 5:30 a.m. every day, switching off again exactly 12 hours later. The humidity level fluctuates seasonally, and would reach an unacceptable aridity in the winter if Dr. Arrold didn’t wet the floors and run a fogger during the coldest months.

Based on the pictures of the racks they're using, it looks like you can fit ~84 mushroom logs per 5' square area devoted to growing, including room for walkways. It says logs are "made by mixing steamed bran or wheat, sawdust from thirty-year-old eucalyptus, and lime in a concrete mixer, packing it into plastic cylinders, and inoculating them with spawn", but for the sake of argument lets just say you'll be using some decaying vegetation from your nearby forest, used straw from your farmworkers' bedding, bat guano you collect from the pigeonholes your local bats roost in, and plenty of night soil from your growers and the other denizens of your subterranean community. The article also mentions that (at least in the case of Shiitake mushrooms, which he says are the most troublesome to grow) a log is crops after a week of exposure in the light, then goes dormant for about 3 weeks, then is productive again for 3-4 weeks. Let's imagine that every log produces half a pound of mushrooms over a productive week (I made that up, but its maybe believable). Thus, a single log of shiitake produces about 2 lbs of mushrooms over a 2-month-or-so span of time if my productivity guess is somewhere close to reality. Meaning a 5' square growing area produces around 20 lbs a week on average if it can be kept productive.

Of course, that space calculation only applies to growing space, which must receive light somehow for part of the day and be kept at the proper humidity. You'll also need a fully dark place to keep your dormant logs, but as these can be packed without regard for growing space and the logs are dormant for only 3/8 of the growing weeks, you can probably get by with 1/10 as much dark space as growing space, if you put in some nice shelving to keep things organized.

Of course, you'll also need a master mushroom grower and some obedient workers who can harvest the mushrooms, keep the floor properly wet, and rotate growing logs to and from the dark as appropriate. If you're using a humanoid tribe as your crew, your shaman or medicine man may already possess the requisite growing knowledge or be willing to learn it (otherwise you'll have to bring in an outside specialist, which is definitely going to cost you more of the profits). While your males form your war-party and go raiding, hunting, and trading, your females and younglings can be kept reasonably occupied tending the farm.

Economics: Not only are mushrooms a good food source, but some varieties have noteworthy medicinal, hallucinogenic, poisonous, or (depending on your locale) magical effects. You'll want to balance your growing operation to provide as much cheap food as possible for your growing crews and their families, while maximizing the trading possibilities for your surplus crop. Probably this means growing quite a few more edible mushrooms, but special mushrooms can bring a much higher premium for particular clients willing to pay for them. Here's a list of possible client preferences:

• Demonic cults will often be interested in hallucinogenic mushrooms for their ceremonies


• Assassins may be willing to pay a premium for particularly potent poisonous mushrooms, but you'll have to balance that against the dangers of growing them


• Wizards and witches often have need of particular mushrooms as spell components - at first these will probably be special orders but as you gain a sense of what varieties they require you can expand this part of your growing operation


• If your growers can function in complete darkness, they can grow so-called 'shriekers', which emit a high-pitched noise when light falls upon them. These are useful both around the perimeters of your community (where intruders using light are likely to trigger them, and as trade items for other dark-dwelling denizens.


• Check with your local sages or shamans to find out more about the local varieties available to you

Happy growing!

The Cave of the Seven Sleepers

The Cave of the Seven Sleepers is a man-made ritual complex in Turkey, near Ephesus, where seven dudes (and a dog, if you prefer the version in the Koran) were entombed alive during the persecutions of Decius. They went to sleep and woke up 200 years later, which is a pretty cool story.

Click on the image for a larger version. I imagine a setup like this: Forbidden catacombs, sealed off by a cruel emperor ages ago. Intrepid explorers expect the restless dead, but when they crack the seal, they wake up a bunch of confused guys speaking an archaic version of the local language and marveling at tempered steel and bullseye lanterns.

Case Study: Underground Cities of Cappadoccia

In the central steppes of modern Turkey lies an area of fascinating natural beauty and even more fascinating subterranean architecture. In Cappadoccia there are numerous dwellings, churches, and other buildings carved into the rock and built from bricks of the same.

More impressive are the underground cities, built by early Christians as places of refuge and dwelling. So far eight have been found, but there are probably more. The largest, at Derinkuyu, was accidentally discovered in 1965 when a man cleaning his house accidentally broke through a back wall and discovered a chamber, which led to more chambers, then more. at Derinkuyu there are at least eight separate levels extending down 85 meters below the surface, including chapels, a baptismal font, grain storage areas, and dwelling areas.

Geology: Obviously, the type of rock available in Cappadoccia is an important factor in enabling all of this construction. It's a particular type of tuff, which means it's compressed volcanic ash. The less-compressed areas have then been eroded, leaving solid masses of tuff that can be easily carved and excavated. It is easily cut into bricks for use aboveground or in dividing walls. Anyone looking to build a similar site should look for semi-arid areas of previous volcanic activity that will have built large columns of appropriate tuff. Even workers with relatively little previous stoneworking experience should be able to construct and expand subterranean dwellings in this material.

Ecology:
Although the soil itself is rather sandy, it is volcanic and nutrient-rich. In order to make it fertile, residents here carve decorative pigeon-holes into the rock faces for doves to nest in and harvest the guano, mixing it with the soil. Aboveground crops of grapes, apricots, and wheat can be dried and stored for long periods underground. If larger underground chambers were present, pigeonholes in subterranean caverns could be inhabited by bats and the resulting fertilizer used in mushroom production.
"Pigeon Holes", Uploaded by Verity Cridland on 11 Oct 08

Defensibility: One advantage of interspersing numerous hand-carved cave dwellings honeycombed into a mountainside with entrances to a larger underground lair is that enemies won't know where the real entrances are. This would be much harder to accomplish in a harder stone such as granite. Furthermore, the ease of carving means that it's easy to construct elaborate labyrinths beneath the earth that make it difficult for trespassers to find their way in.
IMG_0326", Uploaded by lesleyk on 23 Aug 05

Rooms: Eel Tower

At Ripley Castle there's a plaque on a sealed-off tower that marks it as the Eel Tower. I'm pretty sure every castle or dungeon design can benefit from the addition of an eel-breeding area. For one thing, feeding all your denizens can be quite a challenge, and not everyone likes fungus and rats all the time. Plus, a trapdoor chute or two into the eel-pit is a pretty cool trap and keeps the eels fed.


Of course, this makes me think of the Mighty Boosh episode about eels:

I bet I know what song you'll be singing when you add the Eel Pit to your next dungeon!

Dungeon Design: How to Host a Dungeon

How to Host a Dungeon by Tony Dowler. Solo play (but can be done as a group); takes a few hours and you'll end up with a good side-view of a subterranean dungeon complex for fantasy play and a good sense of its history and how each part of it was formed and populated.

This can be a satisfying activity in itself, or it can be done as a precursor to 'overhead-view' traditional dungeon mapping for an RPG.