Integrated Pest Management · Agriculture and Natural Resources
University of California
Dormant or delayed-dormant season controls
Dormant controls are applied during the fall, winter, and early spring to control over-wintering insects or to prevent disease after deciduous trees have lost their leaves and before new growth develops. Delayed-dormant controls are applied as buds begin to swell.
- Clean up mummies and old fruit in and under trees.
- Remove fallen leaves from beneath deciduous fruit trees and roses.
- Prune off dead, diseased, and borer-infested wood.
Prune deciduous trees and shrubs that need pruning e.g., apple, crepe myrtle, pear, rose, spirea, and stone fruits. Except certain pests and host plants warrant summer pruning e.g., shothole borer, apricot, and cherry.
Specific invertebrates and diseases for which dormant sprays may be applied
- Applying dormant or delayed-dormant treatments – general treatment
- Aphid eggs
- Branch and twig borer on grape
- Cutworms on grape
- Dryberry mite
- Grape mealybugs
- Peach twig borer
- Pear psylla
- Redberry mite
- Scale insects
- Western tussock moth
- Botrytis fruit rot in caneberries
- Brown rot of citrus
- Brown rot of stone fruit
- Downy mildew on caneberries
- Downy mildew on grape
- Eutypa dieback on apricot and cherry - avoid winter pruning
- Eutypa dieback on grape
- Leaf curl fungus of peach and nectarine
- Leaf spots on caneberries
- Phomopsis cane and leaf spot
- Powdery mildew on fruits and berries
- Powdery mildew on ornamentals
- Rose diseases (black spot, Botrytis blight, powdery mildew, rust, rose phyllody)
- Shot hole disease, or Coryneum blight, of almonds, apricots, nectarines, peaches, and other Prunus species