Q: My husband is about to put up Christmas decorations. He always just pounds long nails into our trees and then hangs the wire.

I feel this must be doing damage to the tree - he says the tree doesn't even notice it. Which is true?

A: Any time a tree is wounded, damage is being done, and driving nails into a tree wounds it.

However, when we prune a tree we are, technically-speaking, wounding it, so it's all in HOW it's done as to whether or not actual "harm" is being done to the tree.

I DO NOT condone driving nails into a tree, but a nail here or there probably will not harm it irreparably.

If your husband drives nails into the trees, he should be able to re-use the nails year-after-year, so pounding fresh nails in every year should be unnecessary (and advised against). So, driving a nail into a tree just one time really shouldn't bother it that much.

p.s. The tree DOES notice it. It begins to form different types of tissue to wall off the area of the injury, which helps limit the spread of decay that may try to occur as a result of the wounding.