Woolly apple aphids can overwinter on the bark at old wounds like pruning cuts. They start multiplying in spring.
Apple powdery mildew is most often found on newer foliage which is covered in spores and mycelium.
All the small spots on this leaf are brown mites. They are a cool-season mite that cause leaf stippling.
It is best to catch fire blight infections early. They will cause the flower cluster to wilt and then turn brown or black.
Exposed green peach aphids from a curled leaf. The white structures are old, molted skins.
Powdery mildew on peach can appear as bright white spots or "rusty spot" where the skin is russeted and brown.
Fire blight bacteria overwinter in old infections such as cankers. Bacteria are spread from flower to flower by wind-driven rain, and by pollinating insects.
Fire blight infections happen through flowers. Infections cause the flower cluster to wilt and then turn brown or black.
Critical temperatures for damage to 10% or 90% of peach blossoms.
Large wind machines moves air to raise temperature by 1 to 4 degrees over 10 acres.
Frost-damaged peach blossoms.
For frost protection, make sure the covering goes to the ground. Image courtesy Haxnicks Gardening.
Spider mite feeding damage to cherry.