Berckmann's Blight
Hendersonia coniothyrium
3 host plants · Fungal
Last updated
This profile contains verified disease data from extension databases. Regional field notes and expert review are in progress.
Young shoots blacken and die as this fungal disease spreads downward. Remove affected shoots and improve air circulation.
Remove blighted tissue promptly, cutting well below visible symptoms. Improve air circulation by thinning dense growth. Avoid overhead watering, especially during bloom and new growth periods when tissues are most susceptible. For recurring problems, preventive fungicide applications timed to protect new growth can reduce infection, but cultural controls should be your first approach.
Quick Reference
Management
Do not use Lilly Miller Microcop Fungicide in spring. | Apply again in early spring (February to March) if disease is severe. | Growth at the tips of branches is infected first, turning brown in late spring.
Cool wet conditions; rain splash drives spore dispersal.
Cultural Controls
- Berckmann's arborvitae (Platycladus orientalis var.
- conspicua 'Berckmannsii') is especially susceptible.
- American and European arborvitae are not infected.
- Prune out and destroy infected branchlets and twigs.
- Avoid overhead watering.
- Provide proper culture.