Tell us about yourself!
The tree in this experiment could be replaced by a potato without having any impact on the experiment. The source of this electricity is not the tree, but the zinc coating of the galvanized nail. I did do the instructable, though, since my arduino powers the door to my chicken coop which is in the orchard, and trees are quite abundant, there. This copper kills trees business is rather alarming, though. I'll remove the nail after all, just in case.