Landscape and Nursery - Snow and Ice Damage

With the potential for the first snowfall soon at hand, the topic of ice and snow damage to woody plants is very timely. The following is a short article on the subject.

Ice and snow accumulation on branches can cause internal splits or cracks, bark tearing and/or breakage. Plant architecture, branching structure and wood strength can be predictors of damage from excessive snow or ice load. Unfortunately, hidden cavities in the wood or flaws in branch attachment can increase the damage potential. Plants with multiple stems can be tied to provide support. This may be especially helpful on upright narrow-leaved evergreens. Excessive amounts of snow can be carefully removed to alleviate the stress on lateral branches. Ice should be allowed to melt naturally. Branches become extremely brittle when laden with ice. Mechanically removing the ice may increase the amount of injury. Once the ice has melted, the branches will usually return to their normal positions.


Ice damage to tree. Photo by Joseph O'Brien, USDA Forest Service, Bugwood.org

Heavy snow load can break branches. Photo by Joseph O'Brien, USDA Forest Service, Bugwood.org.

Information from a section of "Abiotic Plant Disorders - Symptoms, Signs and Solutions A Diagnostic Guide to Problem Solving" by Robert E. Schutzki and Bert Cregg, Departments of Horticulture and Forestry, Michigan State University Michigan State University. Go to http://www.ipm.msu.edu/cat08land/pdf/9-19abiotic.pdf for the full factsheet with photos.