Fond du Lac, WI (WHBL/KFIZ) - An Eldorado man was seriously injured when he was pinned by a tree while using a chainsaw to cut it down Saturday afternoon. Fond du Lac County Sheriff’s officials say the 39-year-old man was attempting to cut down the tree when his chainsaw got stuck. While trying to dislodge it, a large portion of the tree broke off and fell on him. He was flown by Flight for Life to Theda Clark Medical Center with serious injuries.