Anybody know anything about squirrels?

There is a squirrel in my neighbourhood I am concerned about. It is a black squirrel and it looks like from the head down to it's front legs it has been shaven and then the hair has begun to grow back. This fur looks soft, not stubbly and it is a different colour, more like a grey. Then there is a completely bald spot by it's shoulder. I am really worried about this poor animal. It has been like that for over a week. Any thoughts on what it could be? I live in a rural area and there is no way any humane society is going to come to try to catch a squirrel. Should I get a trap and try to catch it and bring it to a vet? Suggestions ae much appreciated.