Knocking in Pierce County, Washington

R. and I were walking up the road at about 6:30 pm. We were doing a follow up investigation of the area after hearing of a sighting of bigfoot. We had some wood and paper but I forgot matches at the truck so we had to turn around and walk back to the truck. We had walked through a half mile of woods and through a clearcut about half mile wide. On the way back to the truck and upon leaving the clearcut and entering the woods, I felt the hair raise on the back of my neck and I thought it might be because it had gotten dark and my senses were playing tricks on me. But after walking through the woods a quarter mile and getting closer to the truck, we both heard very distinct and loud knocking of a piece of wood striking another piece of wood about 12 - 15 times. The noise was coming from near my truck. Then we heard two more and it stopped. We got to my truck and I realized I had left my dome light on. We grabbed my spotlight and waited near the truck for a half hour to hear more knocking and we also knocked two pieces of wood together ourselves but couldn't get a reaction. I shined the spotlight into the forest and suddenly we heard what sounded like a big man take off at a sprint though the woods. I know what deer and elk sound like and this sounded like two feet running through the woods at a sprint. This was no deer or elk. My heart started pounding. We waited at the truck until 8 pm when another truck came down the road so we left. We didn't hear anything else but noticed the dogs would start barking in certain areas and then stop but I didn't think that was significant evidence of anything unusual.