I live in southern Alberta, Canada and I have 2 Manitoba Maples in the backyard, one of them have been heavily infested with green aphids last season. It's taken care of now, but the trouble is with the other one. The trees are about 4-5m apart, and about 40y old, the second tree just stopped growing any new leaves, it was fine last summer, but only one small branch could be seen with new green leaves. I guess its dying so plz help! Can I still save it?