May I Request an ID on an Egg Mass?

In early July I was hiking a state game lands area of south-central PA and while exiting toward the parking area I noticed a foamy 'mass' on a tree trunk. The mass was near perfectly 2" round, adhered 'flatly' onto the bark of a tree and located about waist high. It was similar in coloring to a mantis' ootheca but perhaps a bit darker brown.

Honestly, it was the end of a long, hot day and I failed to notice the tree species...which I recognize would probably be helpful. I also recognize I could have returned at a later date to observe it again, but to be truthful it was our first time hiking the area and it was not really worth a return trip.

I have a good photograph of the mass...but I did not want to post until I verified if eggs, egg masses and egg casings are permitted for ID submission.