Silver Leaf

On blueberries, plums, and sweet cherries, look for leaves that turn silvery or metallic gray on the upper surface starting in early summer, usually on scattered branches that lose vigor gradually over two or three years. The fungus spores land on fresh pruning wounds, particularly when cuts are made within a week of rain, and the infection spreads internally toward the root crown. You'll eventually see branch dieback and reduced fruit production, though the affected plant may linger for years if you manage it carefully.

Silver leaf thrives when you prune at the wrong time in Western Washington's wet climate, so timing your cuts matters more than chemical treatments. The fungus only fruits on dead wood, making pruning piles a major infection source: burn all trimmings or remove them from the site immediately. Prune blueberries and cherries in dry late summer after harvest rather than in dormancy, when fungi are actively spreading. Removing heavily infected branches or replanting from healthy root suckers are your most effective options for restoring productivity.