I have a 16-year old corkscrew willow that is easily 30 feet tall. Last winter we had an ice storm which caused severe damage to the tree in that several major branches broke. It leafed out pretty normally this summer, but I've been noticing that the bark is coming off in several places. It looks as though there is no replacement bark underneath. Is the tree dying, or is there something I should do? Thank you for your help!