You drink water from copper pipes and eat food cooked in iron pans. So I see no avenue for danger here

agree with cckw

Me too.

Copper and iron are minerals essential in the diets of human beings. Sometimes fruit trees/plants are deficient in iron and iron is sprayed on the foliage in the form of a chelate. Copper is commonly sprayed on peach trees during the dormant season and sometimes on apples during the growing season.

I'm spraying a form of it on my tomatoes every week to hold back early blight. It is an organically certified product.

I can assure you those are not copper nails. Besides being rare (rarely used in roofing specialty jobs)...copper driven into a tree is the best way to kill a mature tree. That tree would be dead in 2-3 months. Anyway, as stated above, there is no health issue.

It is hard for me to believe that copper nails could be such an affective tree killer. You sure about that fireduck? Sounds like a great way to discretely eliminate annoying trees on adjoining property such as state land if it actually works.

My neighbor has a pine that shades out my yard for several hours a day. Copper nails did you say? (Isn't copper too soft to use as a nail?)

MYTH!!!

Yeah, google "copper nails kills trees myth" and you will get a very long list of sources reporting this as a long held myth about trees. Didn't see any support for the supposition.

Copper pipe has been used in the past as a cheap alternative for tapping maple trees. In a good year they would have been left in for at least 2 months. A guy I know said his family used copper pipe spiles and trees were not affected by it.

As the saying goes, "It's the dose that makes the poison." Success probably depends on (1) the type of tree, (2) the health of the specific tree, (3) the amount and distribution of copper, and (4) the time exposure. I get the feeling most people underestimate the amount of copper and time it takes for this method to work. The myth seems to be that a few copper nails are like a silver bullet.

Now I feel the need to experiment on a bunch of trees that will need to be cleared in the next few years anyhow. I'm curious to know how many nails it would actually take in a typical situation. Of course It won't be comprehensive, but I'm might be able to get feel for it myself.

Do the research and I think you will see that the only damage will come from the physical injury of the nails themselves, not their content. Save you the trouble and expense.