I remember a few details about this movie I saw in the late 70’s.
I think they were a Boy Scout troop going to camp. There was some sort of creature or an alien in the same area. The scariest thing about the creature was that it had these living fleshy discs that it threw at its victims. When one hit you, it would sprout some kind of roots or tubes and if you didn’t get it off right away it would drain all your blood. There was a guy living in those woods (ie. A Hermit) who knew about the creature and in an open field he dug a whole bunch of pitfalls to capture and kill the creature. Quite a few of the troop died as well as the troop leader. The creature did eventually get killed.