The influence of forest management on vulnerability of forests to severe weather

Abstract

Excessive wind, ice, and snow regularly cause major disturbances to forests in many parts of the world, significantly impacting both ecological conditions and economic returns to forest landowners. These events cause immediate losses for landowners, and the broken and uprooted trees left in the wake of a storm increase the risk that wildfires, disease, and pest outbreaks will cause secondary damage to the surviving trees. Although weather severity (e.g., wind speed and duration, or form and amount of precipitation) is clearly an important factor in the occurrence and severity of forest damage, site conditions, tree characteristics, and stand characteristics play a major role in determining resistance of a forest stand to wind, ice, and snow loading. However, the relationships between site, tree, and stand characteristics and weather damage are complex and vary spatially and temporally. In this article, we review and synthesize the literature on the risk of forest damages from severe weather—focusing on wind, ice, and snow—and the factors that influence vulnerability. Forest management decisions are found to play an important role in influencing risk associated with severe weather events. The risk of damages can be managed through strategies such as selection of planting site and species, stocking, and selection and timing of silvicultural treatments. Optimal management strategies under endogenous risk vary based on the probability of damage and management objectives.