Kinnikinnick: Rust

categories: Kinnikinnick Kinnikinnick Diseases Ornamentals Shrubs

revision date: 2022-12-03 12:00

Rust pustules on underside of serviceberry leaf and on petiole.
Rust pustules on underside of serviceberry leaf and on petiole
Photo by: R.S. Byther

Biology

Kinnikinnick rust is a fungal disease of the leaves which requires an alternate host (spruce) to complete its life cycle. Symptoms of rust on kinnikinnick are seen in late spring, when the undersides of leaves develop an orange to brownish powdery coating of spores. Severe infections can cause leaves to drop. This rust fungus also causes a broom rust of spruce. Infected spruce trees develop large golden yellow witches’-brooms which may reach up to two yards in height.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Remove infected spruces from vicinity of desired kinnikinnick plantings, and vice versa.
  • Pick off and destroy (do not compost) infected leaves when practical.
  • Rake and destroy fallen leaves under infected plants.
  • Avoid overhead watering. As with many fungal diseases, rust infection is favored by moisture on the leaves.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • None recommended