Definitive way to tell if wood is pressure treated?

[Badfish740]

I was at Lowes today and saw a pallet of dunnage sitting out front. I asked what they were doing with it and the manager told me I could have it for $5. The pieces average about 4' long and vary from 2.25" x 1.5" to 2.5" x 2.5". I separated out the clear straight pieces for an upcoming boat building project, and piled the rest outside for campfire wood. The trouble is, as I was sorting, every so often I would come across a piece with the telltale dark green tinge of pressure treatment. However, a lot of pressure treated wood these days isn't green. A lot of the stuff is stamped "HT" just like a heat treated pallet would be, but I'm worried that some of what I picked up might be pressure treated. Is there any good way to tell? If not, I'm sure I can find some use for it that doesn't involve burning it.

 

[Jags]

Sight is about the only way that I know of. Generally, if you cut into one (cross cut) you will see a penetration line where the treatment ends. Standard PT usually doesn't see full penetration of the wood, just the outer xx of the wood.