I went back and took more photos and observations of the felled tree by the trailhead. I observed that there are apparent exit holes on the top side (the cut edge) of the stump. I searched the felled part of the tree and did not observe any holes on the cut edge of that tree. The stump appears to continue to otherwise be in good condition and have living cambium.
It appears that the exit holes occurred AFTER the tree was felled.
I have not contacted the park yet, as I still want to know more about their own ALB surveying and why they cut down and left several trees on the trail.
(I suspect that the beetle contamination to the living stump could have been caused by poorly cleaned felling equipment, used from another contaminated site.)
This trail shows a good number of living and Felled trees with Bug Damage. I did get to take pictures of and record several separate tree sites. Several trees were already felled and had prevalent small exit holes (possibly EAB) they had been marked with orange and blue hashes. The living trees showed a variety of hole sizes and shapes. A rather artistic bore track was noticed a a couple trees where the borer had made several whirling tracks and the bark had fallen off. I will post the pictures for I.D. A felled tree near the Trail head had some very round, pencil sized exit holes where the bark had been removed.
Did a Brief ALB Survey at this Nature Preserve. I observed bug damaged to downed trees immediately At the turnaround point in the mapping trail I observed a bug damaged live tree, over 60 feet tall, deciduous hardwood. I took multiple sample of bug parts and casings for analyzing later. The photos I took of the damage and the whole tree did not save. I planned to ID the tree from the photos. I will return to this preserve in the near future as there does appear to be evidence of unidentified beetles.