|MadSci Network: Agricultural Sciences|
Yes, if the nail is big enough to harm the base of the tree. It can open an entry for infection and disease. You also need to consider how big is the nail and the tree. Driving a copper nail has physical, chemical, and biological actions playing together. If the tree dies, it will not be easy to know precisely what the main cause was acting. Copper as a metallic form is not harmfull to tree nutrition. It needs to oxidize, to solubilize and then be absorbed. Absorption of copper at the bark level may not occur, while high levels of copper ion in the soil rooting system may lead to toxicity. Many species of trees also will respond differently to this stress related to nails in their bases. In biology we do not play yes/no answer!
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