Quince has bumps with powdery orange backsides
Thanks for the response. I've gone ahead and removed all visibly affected areas (leaves, mostly) and put in the green bin. Is that a suitable treatment given the time of year we're in?
I wonder: there's no cedar/juniper here. How far does it spread? Could it have come from 150ft away, for example?
The fungus spores move on the breeze. So, yes, 150 ft is possible.