Will 1 copper nail kill a tree?
Continue hammering nails in a ring around the tree, about one-half inch apart. ... The idea that one copper nail will kill a tree is only true for very small trees, such as saplings. Larger trees can tolerate a single nail without issue and will simply grow over the nail in time with no ill effects.
How do you kill a tree with copper wire?
The technique for killing trees with copper nails is quite simple. Purchase 100% copper nails and pound them into the tree. I have heard of people using one nail or hammering them in all the way around the tree. Once they are in let the tree sit until it dies.