My guess would be winter injury. After injury like that it's a buffet for lots of critters that won't attack an uninjured tree.

I have to agree with fruitnut. When did you notice it? If you weren't already aware, Pruning your tree may help the situation solve itself.

Here is a link that might be useful: Tree Pruning

Thank you all!

Hm...good point! This is of a young tree,..say about 6 years old,
about 4foot up I cut the center off when I noticed the top was dieing and a side branch. Another tree, lots older, about 35 years old I've been cutting off side branches,..several over the last 5 years or so and for some reason I believed some critter was doing damage under the bark.

Looks like Ash borer eggs 2013 damage They lay eggs in crack bark no hole boring. They came to USA from Russia in pallet wood in 2002 discovered. Wood transfer may happen to your area. Any borer spread if trees cut near by half mile around farm should come up with source borers.

What happens when you squish them?

THEY MAKE A SQUISHING SOUND ;)

I didn't squish...do next time when I find,... thank you all!