I have a crop of sweet potatoes with some the size of large footballs I imagine since I was good at soft ball and pitching that if I launched one of those at someone's head region I could knock someone out. Then you have firewood too a good chunk thrown or catapulted could do some major damage as well .
Not to mention iron based fry pans thrown by the handle with accuracy can bring someone down too, ask me how I know . Ex husband was an alcoholic and violent and came in swinging at me and I threw one at him and knocked him out cold from the other side of the room.