Swiss needle cast
Nothophaeocryptopus gaeumannii
0 host plants · Fungal
Last updated
This fungal disease causes infected needles to become off color and mottled yellow or brown. The needles may turn completely brown and are usually dropped prematurely, often in early spring.
Start with sanitation: remove and dispose of affected material as you find it. Thin dense growth to improve air circulation, and redirect irrigation away from foliage. If the condition persists despite cultural adjustments, your local Extension office can help identify the pathogen and recommend targeted treatments.
What Should I Do?
- Avoid planting in low-lying areas with poor air drainage
- Space plants for good air circulation
- Control weeds around the bases of trees
Quick Reference
Management
Spring, when new shoots are 1 to 2 inches long and rapidly expanding. Spore infection occurs through stomata of young needles." # source: "PNW Plant Disease Management Handbook
Cool, rainy spring weather; variables associated with increased moisture (fog, rainfall, altitude); warm winter temperatures; absence of excessive summer heat. Production of pseudothecia is related to winter mean daily temperature and spring cumulative leaf wetness." # source: "PNW Plant Disease Management Handbook
Cultural Controls
- Avoid planting in low-lying areas with poor air drainage PNW Plant Disease Management Handbook
- Space plants for good air circulation WSU HortSense
- Control weeds around the bases of trees PNW Plant Disease Management Handbook
- Avoid seed from susceptible trees; use low-elevation coastal provenances PNW Plant Disease Management Handbook
- In heavily diseased areas, plant species other than Douglas-fir PNW Plant Disease Management Handbook
- Remove and destroy infected trees from Christmas tree plantations WSU HortSense
Swiss needle cast is native to the Pacific Coast and is considered one of the top threats to Douglas-fir plantation health in western Oregon, Washington, and SW British Columbia. Severe aerial-survey-visible symptoms are concentrated in the Oregon Coast Range (Tillamook area), though the disease occurs throughout western Oregon and Washington. The disease is most severe in coastal fog zones but affects Douglas-fir of all age classes across the maritime lowlands. Cool, rainy spring weather typical of the Puget Sound region is conducive to spore dispersal and infection. Mild maritime winters with sustained warmth favor pseudothecia production." # source: "PNW Plant Disease Management Handbook
Sources & References
Primary: PNW Plant Disease Management Handbook
- WSU HortSense - Douglas Fir: Swiss needle cast (
- Wikipedia - Nothophaeocryptopus gaeumannii (
- Shaw, D.C., Filip, G.M., Kanaskie, A., Maguire, D.A. and Littke, W.A. 2011. Managing an epidemic of Swiss needle cast in the Douglas-fir region of Oregon: The role of the Swiss Needle Cast Cooperative. Journal of Forestry 109:109-119.