Timber from chopped down trees is processed in a variety of ways depending on its intended usage. Timber intended for building, for example in roof rafters is often cut to specific shapes and sizes.

Problems
People who make a living working with wood have to aware of a variety of things. These include fungus, animal influence, and natural effects.

Fungus and animal infestation can cause wood to decay, and clearly a decayed piece of timber is not suitable for much, especially usage in construction!

Because of this timber is often treated with preservatives such as pesticides to eliminate these problems, and maintain the integrity of a particular piece of wood.

Timber which has already been affected only really has usage as an energy source in log burning stoves for example. This converts the energy contained within the timber into heat energy for the purposes of heating homes.

Sustainable?
The timber industry is subject to much debate because it destroys animal habitats, as well as visually pollutes.

The large machinery that is used to actually cut the wood further adds to the problems by compacting the ground amongst other things.In extreme circumstances removal of large volumes of trees can instigate processes with lead to desertification.

Such is the extent of the problem that sustainable forestry is being encouraged: any trees removed, must be replanted, or rather trees must be coppiced whereby the tops of the trees are cut, and they are then allowed to regrow.

Not only does this sustain the area, but it makes wood to some extent a renewable, and infinite resource.  It would be illogical for people in the business not to replant trees, as it is their money source !