Yellow Rust
Phragmidium rubi
14 host plants
Last updated
Red raspberry leaves show yellow-to-orange spots in spring and early summer with orange spore pustules on leaf undersides. Phragmidium rubi fungus overwinters on trapped old leaves. Fruit dies before maturing if infection is early. Remove old canes immediately after harvest. Strip leaves from primocanes before tying. New races now infect previously resistant cultivars like 'Meeker' and 'Willamette'.
Burying fallen leaves, old cane stubs, and refuse before new leaves appear will help eliminate inoculum sources. In home gardens, destroy fallen leaves and other refuse.
Quick Reference
Management
By fall, these pustules turn dark brown to black. | On the lower surface of the leaf in positions corresponding to the yellow spots, orange to pale yell | Train canes after leaf drop or strip leaves before tying.
Cultural Controls
- Burying fallen leaves, old cane stubs, and refuse before new leaves appear will help eliminate inoculum sources.
- In home gardens, destroy fallen leaves and other refuse.
- Remove and burn old fruiting canes as soon after harvest as possible, cutting flush with the ground.
- Cultivate as soon as weather permits.
- Strip leaves from primocanes before tying.
- Postpone trellising primocanes until leaves drop off.