Question
hi jim!
I have a holly tree on which i am seeing diseased leaves as we turn from winter to spring. Some of the leaves, normally a healthy dark green, are showing black spots, or appear half-eaten away with a gray border, or are completely turning to a light, almost yellow appearance.
I did not see this problem last year, or for many years, but i did see it 6-10 years ago.
i have removed as many of these sick leaves as possible to prevent cross-contamination, but i don't know whether this will help.

Your advice, please.

thank you for your interest in this matter

chris

Answer
It sounds like you have Powdery mildew, a disease of leaves of many plants. To control this disease you will need to spray the leaves (both sides) with a fungicide. There are several that will work and since I am not sure if one can be found in your location I am attaching a web site that discribes the disease and controls.
http://www.ext.vt.edu/pubs/plantdiseasefs/450-603/450-603.html