These pictures are of the stem wall located at the garage. The home was built in 2004. It looks like they left the forms in the concrete. My concern, is this going to be a structural issue 10 years down the road when this wood rots? I have never seen this before, and it really does not make sense where the wood is located.
Yes if that wood is in contact with the ground it will be an issue but I would be more concerned about WDO wood destroying organisms.
This is a perfect path for them to get in undetected.
Sometimes contactors insert pt wood into poured wall as nailers…
That would be my guess. The wood itself will never become a “structural” issue, but if it’s not being used it should be removed.