Fun With Tree Spiking

What? - Basically, when you spike a tree you hammer a large hardened nail into the trunk of the tree.

Why? - Tree spiking helps ensure the woods/trees that you spike will not be cut for lumber/pulp and that the forest will move towards (or remain in) a climax, old growth state. The spike can damage both the value of the wood and the equipment used to 'harvest' and process the tree.