Using Treated Wood for Horse Fencing

Good-quality pressure-treated wooden fence posts can be expected to last about twice as long as nontreated posts. That’s the good news. However, the chemicals used in treatment don’t sound like part of a healthy equine diet. Is there a real danger in allowing horses to be exposed to pressure-treated wood?

According to an article in the University of Minnesota Horse Newsletter, there is little to no risk of horses being seriously affected by the chemicals in treated wood used for fencing. Horses usually don’t swallow wood although they do chew on it, and they would have to ingest large quantities of treated wood to be harmed by the chemicals it contains.

For horses that are cribbers or wood chewers, posts treated with copper naphthenate (Cu-nap) are the safest if horses actually ingest the wood. To discourage horses from these habits, owners can install a single line of electrically charged wire along the top of the fence.

Using treated wood for feed storage bins where feed products are in direct contact with the wood is not recommended.