Needle Cast, Swiss
Nothophaeocryptopus gaeumannii
4 host plants · Fungal
Last updated
This profile contains verified disease data from extension databases. Regional field notes and expert review are in progress.
Douglas-fir interior needles yellow and drop prematurely from pseudothecia blocking stomates; Christmas trees dry twice as fast. Nothophaeocryptopus gaeumannii is severe in coastal fog zones north of Tillamook, Oregon. Select low-elevation provenances, avoid planting in poor drainage, and thin stands for air circulation in Christmas tree settings.
Silvicultural techniques, such as thinning and vegetation management, have been shown to have no impact on disease severity on forest trees, but will influence stand development and individual tree growth. Cultural tactics combined with chemical management are effective in Christmas tree and nursery settings.
Quick Reference
Management
Bud break through new needle elongation (spring). Preventive fungicide at bud break when new needles are emerging.
Conifer needlecast fungi infect newly emerging needles at bud break in spring; wet conditions during needle elongation are critical for spore germination (PNW Gardeners Handbook Ch 17).
Cultural Controls
- Silvicultural techniques, such as thinning and vegetation management, have been shown to have no impact on disease severity on forest trees, but will influence stand development and individual tree growth.
- Cultural tactics combined with chemical management are effective in Christmas tree and nursery settings.
- Avoid planting in low-lying areas with poor air drainage.
- Space plants for good air circulation.
- Control weeds around the bases of trees.
- Avoid seed from susceptible trees.