Untitled Sighting

11/20/12 I have been keeping my eyes peeled for any potential sign even though I live in a fairly populated area. I live on and drive up and down Carrollton Rd several times a week. What I noticed was a fresh break of a young tree, about 50-60 feet in from the road. Due to brambles, and being private property, I didn't go in for exact measurements but I'm a pretty good estimator. This break is about 6 feet off the ground, maybe 5, the tree is approximately 4-5 inches in diameter. I noticed that there are significant scrape marks on one the road side of the tree, can't see the other side, The marks are ONLY below the break. I also found what looks like definite depressions in the leaf litter, with a bit of compressed bare ground, one about 6 feet in from the road at the tree line, and one about 2 feet from the guardrail. I carry a tape measure with me in my car as part of my tools for farriery, so I was able to lay it out at what I believe is the length of the depressions and get pictures. Of course I couldn't resist doing a few knocks, there were some good rocks at the roadside so I did one knock, waited about 10 seconds then did two more about 2 seconds apart. I waited about two seconds, stood up, took two steps and heard a response knock!!! It sounded like it was certainly past the hill (top is about 3-500 yards from road) and probably well past that, guessing within a half mile. I waited about 30 seconds, put out a few more knocks, nothing. Couldn't help a few short whoops, no response.