Norway Spruce Diseases
As a common evergreen landscaping tree having beautiful conical shapes, Norway Spruce might be infected by a number of diseases which can seriously affect its health. Since tree diseases may be spread quickly from one tree to another, you should keep an eye on your trees and prepare some treatment plans beforehand for emergency use.
The two most main diseases which can severely affect the Norway spruce trees are the cytospora canker disease and Rhizosphaera needle cast. They are both caused by the spreading of the fungus. If you see some yellow spots on the surface of the trunk, it indicates that your tree may be infected by the cytospora canker disease. You may also see some liquid coming out of the bumps. On the other hands, the Rhizosphaera needle cast diseases will affect the foliage of the tree instead of the trunk. The leaves of the spruce tree will turn to brown and fall off from the tree eventually in autumn.
If you are not able provide adequate maintenance for your trees, the above disease may occur from time to time. These diseases may have some incubation period before symptoms become apparently. You should keep an eye on your tree from time to time so that the diseases can be discovered as early as possible. You should avoid over-watering your trees to lower the chances to get infected. You should keep the metal blades away your trees to avoid any cuts or damages on the trunk. The skin of the trunk is very important for trees to protect them from fungus infection. If your trees are already infected, you can use some fungicide to kill the fungus in your tree and cure those diseases quickly. To avoid the spread of the diseases, you need to remove the infected parts as much as you can. Use some fungicide to clean the cuts thoroughly. You should consult with some gardening professionals for more information.
Image provided By Axel Kristinsson from Reykjavík, Iceland (Norway Spruce Uploaded by russavia) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons