The company that cut down the tree that was not on your property and who placed it there is responsible for removing the tree completely from your land. If the power company did not cut down your tree, but directed that some tree removal company cut it down, the power company is also resposible for having the tree entirely removed from your land.The job is half done. The rotten tree is cut down but it needs to be removed.You should send a demand letter to the power company stating a due date for its removal. If you do not receive a satisfactory response, you can contact your local city council or supervisor to get help and pressure from them, or pay to have the debris removed and sue the power company for the costs of the removal.Good uck.