Chris Lewis wrote:
According to Retiredff :

AutoTracer wrote:

Thing I don't like about pressure treated (especially 2x4 and 4x4)
is the little grooves cut in the surface to identify it as PT. this
kind of ruins it for exposed work since you shouldn't sand this wood
extensively.

I have never seen any pressure treated lumber with grooves or any
other identifying marks cut into the wood.
Depending on the manufacturer, depending on the size of the lumber,
the mill will "slash" the face of the lumber so the PT will soak in
better. It's not "identifying it as PT", but an aid to getting better
soak of the preservative in shorter time.

Just curious- where the heck are you? Like I said, I've never seen any like
that. Then again, I've never looked outside of the mid-Atlantic region.