First stuff leaching out will go down. Very little will reach out. Yes roots will hit it. If you are really worried slide some metal down - get white metal coil (used when siding to cover posts, facia etc.). Cheap and slide it down. Now roots must go down to get "under" timbers and for sure all chemicals coming off will not go near 99% of roots. Also in a couple years 75% of chemicals or more will likely be gone. I worry a lot but I think you are ok. I used regular wood - untreated. I bought sealer that was nontoxic. Its not working. Been 3 or 4 years and it is not going to be long before some boards break. I now slope soil down at wood to allow less dirt to touch the boards to let them dry in hopes to make them last longer. PT wood would have been thousands (I made BIG beds)

I don't rule out specific colors or shades altogether, but there are colors that I would never use on certain materials, if that makes sense. Some materials have colors that are naturally associated with the material and that's fine. So I would have a terra cotta floor or tile roof in the natural color, but I would think a bathroom painted in terra cotta semi-gloss would be awful. I would have a black leather sofa or black walls even, but I would probably not want black bathroom fixtures. I like cherry and mahogany furniture, but I really dislike the red-burgundy tone of a very popular prefinished floor in new construction here. I would probably buy a beige rug, but I really dislike the beige porcelain variegated tile that is ubiquitous in bathrooms here.

no way, lukkiirish! It's nice to "meet" a fellow GWer! It's funny--I went to an african violet show in Ann Arbor in April and a group of gardenwebbers were in front of me all introducing themselves by their screen names--I almost chimed in but I never post on that forum, just this one! Yes, I was shocked that such a house was back there, amidst all the midcentury ranches and colonials, and a (hated by me) giant Tim Hortons! (My friends and I call that place the "TajamaTim's"...)

What's your counter top? As much as I love the look of blue slate up against a wood floor, it would look weird if it is the ONLY punch of blue/gray in the entire kitchen. If in doubt, look to your counter tops to help pick your floor. It is a very simple (yet elegant) form of DIY Design which helps homeowners complete the look without having all the stress of picking 'another colour' for the floors.