Knowledgebase
Norway Spruce browning branches #929596
Asked April 25, 2026, 12:17 PM EDT
Delaware County Ohio
Expert Response
I am sorry to hear about the issue with your Norway spruce.
Norway spruce (Picea abies) is a common and adaptable evergreen in Ohio, but it can decline due to a mix of environmental stress, pests, and diseases. In Ohio’s climate, the most frequent causes of decline include Cytospora canker, drought stress, waterlogging, and insect damage.
From the photo, it is obvious that the damage is significant. But the casue is difficult to diagnose.
Cytospora canker is a stress-related fungal canker that more commonly afflicts 10-20 year old trees. Cankers ususally cause branch death at the bottom of the tree and continue upward; however branch death can be scattered throughout the tree. You can confirm a diagnosis by the presence of an exuded white resin within cankers on afflicted branches.
See:
plant_clinic_report_-_spruce.pdf;
Cytospora canker | UMN Extension
For treatment:
- Water during periods of drought.
- Mulch the soil beneath the tree.
- Prune out and destroy infected branches during dry weather. It may take two consecutive seasons of pruning to significantly reduce the disease. NOTE: Between cuts, decontaminate pruning tools by treating them for at least 30 seconds in 10% bleach or 70% rubbing alcohol. Decontaminating tools will help prevent movement of the fungi from branch to branch. If you use bleach, be sure to thoroughly rinse and oil tools after pruning to prevent rusting.
Roxanne