Living on a Giant Tree - Resources

Question

This is one of a series of questions centered around living on a giant tree. The setting/scenario is described below:

In my fantasy world, elves live on a giant tree, very similar in structure to a Banyan Tree. The elves live on the branches of this tree, which average ~300 feet wide. The tree itself is wide rather than high, only extending 600-100 feet up. The branches are supported by massive aerial roots, as they are in older banyan trees. The elves can descend the trees to the massive fog-covered swamp below, but rarely do, meaning they have to live off of the tree entirely.

This question deals with the natural resources available to the elves, and what, if anything, they will need to survive in addition to what they already have.

Trade is established with the occupants of the massive fog-covered swamp below. Relations are strained however, and resources gained that way should be kept to a minimum.

Some details of the elves' situation are below:

• Aside from the size, the tree is identical to a Banyan. Aside from providing wood, it also has all the medicinal uses of the Banyan. It also provides fruit. I am open to giving it additional health benefits if they are greatly needed.
• Other plants and trees grow on the giant tree, so there should be no shortage of natural food.
• Water collects on the giant tree in several small lakes, so water is available.
• The giant tree is populated with creatures, so meat, skins, and bones are also available.
• Aside from trade, the elves have no way to access metal or rock (unless they can somehow form on a giant tree, which I doubt).
• The elves require weapons and armor.

What additional resources will my elves need to thrive? Or will they have everything they need?

Answer 1

Given that I have no idea how hard of science you're looking for in this answer, I'm going to assume hardish and move on from that assumption. Two problems which I will address in turn.

which average ~300 feet wide. The branches are supported by massive aerial roots, as they are in older banyan trees

Impossible, so we're going to pretend it's a magic tree that can get enough photosynthesizing energy, water, and nutrients. In order to support its own weight, it'll have to be extremely light or extremely hard wood. Given that it wasn't blown over, somehow it's going to have to be both. Aside from all of the tallest trees being hardwood, it'll make some of your elf's other problems easier. You are still left, however, with a rather serious problem.

Weather. On a normal day, your elves can expect 160km/hr wind speed (100 mph). Storms would simply kill them outright. This means your elves are going to be spending most of their time inside the tree, which will sway and bend under the force of the winds regularly -- much like modern skyscrapers. You're going to have to be careful to only inhabit the largest branches and not to kill them via the tunneling for your home.

Aside from trade, the elves have no way to access metal or rock (unless they can somehow form on a giant tree, which I doubt). The elves require weapons and armor.

I'd look at how the ancient Quechua people (the Incas) conducted warfare against the Spaniards, I can suggest a couple of books if you're interested. They did not have access to metals suitable for warfare, while the Spaniards had horses and steel. Aside from that, however, I'm going to suggest you use the wood itself. In order to stand up the conditions that it has to the wood is going to make carbon fibre look like a primitive joke, it's going to be lighter and harder than anything we've (RL humans) have come across before. Due to wind speed, there is 0 point in projectile weaponry until you have ballistics it's pointless. Instead, you'll be getting very deadly wooden edged weapons.

On an unrelated note to the exact question, I'm going to suggest you call the magic tree a gum tree. They're the second tallest type of tree as far as I know, so that works out pretty well. The main reason, though, is that the bark is thin and soft making good clothing. Additionally, the sap can be used as an adhesive and, while not tasty, a food source.

I wrote this quickly so if I'm not clear about something shoot a comment and I'll get back to you. Cheers!

Answer 2

Height is a huge problem here. You might want to go wider instead of taller, because 50 stories up (that's what 600 feet is) conditions change considerably. You need sun to grow things, but at that height, the wind would be so bad that you couldn't do much as far as growing things is concerned. You'd have to place the garden more towards the center of the tree, with nothing blocking the sun. I know that in movies there's always a rooftop garden atop the tall building, but...it does not work at 50 stories.

20 stories up is pretty darn tall, as is 10 stories--so maybe most people don't LIVE in the tallest reaches, unless they are in the center.

The good news is this: you have a power source. We aren't talking high science here. We're talking windmill power. So high up in the trees you might have wind turbines. These could be used to run simple mechanisms or grind seeds (on the ground it would be used for something like wheat). Mills, powered by wind or water have been around since the Greeks, and were in extensive use in Medieval times. They could be used to extract oils from seeds and any number of applications which could help them to process their food resources and make better use of everything they have. This is old, old tech. It can also be used to compress bark and or leather for armor making.

As to the animals inhabiting the trees, and the process of tanning hides, yes a mill can help!! There's something called a bark mill that you should look into.

When looking at water supply, I found myself stumped because we don't know how big your "lakes" are or how many people need to be supplied. You want to handwave the water problem away, you can, but water is heavy, and your tree is already...well, it's big, and a normal banyan would have collapsed under the weight of itself, let alone what was built on it, plus lakes...definitely want to have magic involved, even if it isn't obvious.

I hope they have another source of water other than what falls from the sky--I'd look into the Mayan system of managing rainwater, and apply it to trees.

Do keep in mind that if they are collecting all this water, it isn't falling to the ground, and the tree might need it. (Or it could be in a swampy place and doesn't--just keep it in mind).

Other plants and trees grow on the giant tree, so there should be no shortage of natural food.

The above is going to depend on your population numbers. You've given us size of environment, now we have to figure out how much flora and fauna can live in that space, and at what height, and how many people that would actually support.

I don't know what you expect our answer to be since you list that they have all the water, and food they need. Everything else, like medicine, armor, furnishings and clothes, can probably come from the other stuff they already have.

The thing I would ask, whenever building any civilization, is where does the poop go?