Hi! After a couple seasons of serious bark scale infestation followed by treatment, these trees are finally starting to recover. However, as they are losing the blackened bark, the wood underneath looks like this in many areas. Looking for thoughts on what it is and what I need to do. Thanks!

.... no need for you to do anything. What you see is unorganized tissue (parenchyma) often referred to as wound wood or callus tissue, the tree's natural/normal response to wounding.

Bark consists of dead periderm cells, so as the outer layers of cells on the newly generated tissue die, the wound wood will eventually form its own layer of mature corky bark similar to that covering the rest of the trees trunk/branches.
Al