Spruce Windbreak Problems

Norway Spruce, Richard Webb, Self-employed horticulturist, Bugwood.org

Every year, I receive many questions on spruce windbreaks.  These windbreaks appear to be declining either due to disease, spider mites, environmental issues, cultural issues, or all of the above.  First of all, we always suggest that you submit a sample of the affected branches to our Plant Clinic for an analysis.  For more information, you can go to the U of I Plant Clinic website:  http://web.extension.illinois.edu/plantclinic/  If you have questions about your problem or the sample process, you are always welcome to call (217) 333-0519.

Spruces are generally native to cooler regions and are adapted to cold conditions. They prefer full-sun locations with acidic and well-drained soils. Improper planting techniques as well as plantings in inadequate sites can be detrimental to spruce health. When exposed to unfavorable cultural or environmental conditions, spruce can become stressed and more susceptible to diseases and pests. 

Recently, we released a U of I Plant Clinic Report on Spruce Problems (Pest and Cultural Issues). 

It includes pictures and brief descriptions of spruce cultural issues as well as the most common disease, insect, and spider mite problems that affect spruce each year in Illinois.  It can be found at the following link:  http://web.extension.illinois.edu/plantclinic/downloads/Plant%20Clinic%20Report%20Spruce.pdf

Next, if you continue to have problems with windbreaks, please go to the Illinois Windbreak Manual, which can be found at the following link:  http://web.extension.illinois.edu/forestry/iwm_complete.pdf 
This manual is a great resource.  Some of the helpful information that I often pass on to others from this manual:

• Most Illinois windbreaks will only last 40 to 50 years.  Once they mature, they can decline and lower branches can die.

• Thinning a closely spaced windbreak needs to be done to promote individual tree formation and to discourage death of lower branches.

• It is not good to plant entire windbreak to one species.  Monocultures can encounter serious problems with disease and insects pests and lack of variety of texture.

• Same species should be planted in the same row - minimize shading problems for trees that don't grow as quick as neighboring trees in adjoining rows.

• Remember to maintain, care, and protect your windbreak!

-Control competing vegetation
-Control disease and insect
-Protect from grazing livestock
-Correct Pruning
-Fertilize
-Replant or renovating windbreak when necessary