Knocking in Harford County, Maryland

First of all this is the first time I have ever come forward in writing about this incident(s) that took place approximately 18-19 years ago. Myself, my Uncle and a few hunting buddies frequented a 68 acre parcel of land in Street, MD. One day we were conducting target practice (sighting in our guns) for the upcoming hunting season. It was a warm, sunny day and off in the distance one of us noticed movement in a wooded area across Broad Creek. It appeared that there was a large dark silhouette walking back and forth in the foliage. Every time it walked back and forth it would stop and grab a hold of a large tree and began to shake it. Keep in mind this was a calm warm day and no other trees were moving because there was no wind. I thought it was very unusual behavior and must have taken an enormous amount of strength to be able to shake a tree of this size. I peered through my 4 X rifle scope to examine the object more closely and observed it to walk upright and was covered with dark brownish hair. Its head was large and I could only observe the upper half of the body. When it turned, its arms appeared to be long and muscular and I could see that its back was very muscular too and had a "V" shape to it, which led me to believe that this was no bear. It seemed to be agitated that we were there. After about 15-20 minutes of watching it we decided to leave and never spoke of the incident again. Additional things: In October just after dusk that same year on the same parcel of property my uncle was walking from the the dirt road area through a grassy area down a hill to the barn. I heard him yell and call out to me. I came running thinking he had fell down and I observed him on the ground with his tools scattered all over the ground. I smelled a horrible pungent odor, heard heavy breathing and large foot steps coming from the near by wooded area. It was dark and I could not see anything and I got an eerie feeling of being watched. I got my uncle up off the ground and he told me as he was walking down the grassy trail, he heard long loud foot steps coming up from behind him. Thinking it was one of us playing a prank on him, he braced himself for one of us to jump on his back, however whatever hit him from behind knocked him with such force, he feel forward to the ground causing him to drop his tool box. He said whatever hit him ran into the woods and was grunting and walking back and forth. We both got flash lights and tried to look in the wooded area where we heard the heavy breathing but did not see anything but heard what sounded like bipedal footsteps go down the large decline and cross the creek at the bottom. I am a trained observer and can only tell you what I saw.