Pre-Treated Lumber for Grow-Boxes

Q. Is it ok to use pre-treated wood to make my grow-boxes?

A. Fresh creosote is not good to use, but if it’s aged, like that in old railroad ties, it’s alright.  Also, the treated lumber from stores in the USA have historically had some arsenic in them, but I have been told they must be arsenic-free, starting in 2005.  I would advise anyone using treated lumber to ask the store personnel where it is purchased, before using it.