Talkback: Powdery mildew

Apparently mildew has been a prolific problem this year according to Mail Order Trees from whom I purchased a 2 year old Amelanchier canadenisis which quickly developed the disease. Have pruned heavily and will spray with fungicide.

I have powdery mildew on an red acer tree (I think it's a Crimson King Maple) which is over 25 years old. It had been heavily pruned in recent years to allow some more light in the garden. The mildew has also affected some other plants in the garden, ie my trailing begonias, this year. Should I take the tree out altogether?