Wood is a great building material. It's fairly cheap. It's fairly light. It's fairly strong. What else could you ask for?
Well, wood is a little weak in tension and very weak in shear. Being that it is very commonly used in bending, a great application of its large cross section, this can be a problem. The solution: reinforced wood.
Essentially, wrap a steel mesh around the trunk of a young tree. As the tree grows larger, it will push through the mesh. Eventually, you will have an ordinary looking tree with steel mesh running through it. Chop it down and cut it up. Now, you have steel reinforced wood that is great in tension and shear and just about anything!
(I have to give credit to my father for this one, as it was his idea.)