Look in the corner of your living room, or maybe in the pub you visit this evening, and somewhere you will see the rubber plant. Long lived, almost indestructible, they make excellent house plants, and they are healthy too. It´s been shown that they filter tobacco smoke and other pollutants from the air.
The Rubber plant is not the same as the Rubber tree. Well, actually, you can make rubber from the latex, but commercial rubber is made from the tree Hevea brasiliensis, a Brazilian native that is now grown all over the world. The Rubber plant, Ficus elastica, is a type of fig from India and requires a special wasp to set seed. And, left to it´s own devices it is BIG. Up to 60m in rare cases, although 40m is more normal. The trunk can be up to 2m in diameter.
To help support all this weight the rubber plant produces lots of buttress roots down the side of it's trunk which both help support heavy branches and also anchor the tree. It's also hung like a christmas tree with ariel roots.
These roots can be trained, guided, to grow where you want, and in parts of India have been used to make living bridges across canyons. They will root on the other side and can make narrow bridges up to 100ft long. Not only are they free, but self sustaining and will actually get stronger over time as the roots thicken.
So, how does one make rubber? Well, actually I wouldn't, as the latex is nasty stuff and causes all sorts of skin problems, but if you must, this is how to do it. Make a cut in the trunk and collect the latex that runs out. Coat a thin layer over a wooden paddle and hold high over a wood fire until the solution has set and the smoke has turned it grey. Gradually add more latex, waiting each time for it to set, until you have a big black lump of rubber. Cut for use.