Quince Tree Leaf Spots
I have a quince tree that I planted about two years ago, and it has been afflicted with brown-orange spots on the leaves. The first year, no fruit set (I did not expect any, either), but this year, there were many blossoms and I had a fair number of fruit set. However, it looked like all the fruit dropped. The spots had appeared earlier. Two fruit remain, but the spots bother me. From what I was told, quince are usually trouble-free, so this was unexpected. I would like to know what this might be, and what I can do to remedy this? I've included a couple photos hoping that will help. Thanks in advance! James Spielman
Multnomah County Oregon plant disease
Looks like a common fungal disease that has a simple common name - leaf spot. There are other fungi that can cause leaf spots but these are discrete leaf spots in your image that do not look like rust spots. More info here:
There may be other reasons for the lack of fruit which could be due to either rust or brown rot - both were common this spring.