Freezing-Rain- and Snow-Induced Bending and Recovery of Birch in Young Hemiboreal Stands

Abstract

Damage to birch (Betula spp.) trees after an extensive freezing rain and snowing event was assessed in hemiboreal stands aged from 2 to 30 years. Tree diameter, height, and stem bending were measured, stand age and time of thinning were obtained from inventory data, and the relative distance from a sample plot to the nearest adjacent stand was calculated. Stem bending was remeasured after one and three growing seasons to assess tree recovery potential. Stem damage was found for 31.0% of birch trees, with 93.7% of them bent. The probability of being bent was increased (p p p p p p p < 0.01, respectively). The results indicate the importance of timely thinning that maintains a stable tree form and is performed considering the spatial planning of heterogeneity in the heights of adjacent stands to avoid damage at a young age.

Keywords

• relative diameter
• freezing rain
• recent thinning
• slenderness ratio