Woody Plants Affected by Ungulates in Winter Period, Impacts and Bark Renewal

Abstract

Abstract Due to biotope fragmentation and changes in landscape structure, opportunities for forest animals to migrate and obtain food are diminishing, especially during extreme winter conditions. The main objective of this research was an assessment of ungulates, impact on woody species, evaluation of damage forms and bark renewal phases of affected woody plants. The study area is located in western Slovakia in the southeast part of Male Karpaty Mts. After the very cold and long winter of 2012/2013, 34% of woody plants were damaged by bark stripping and biting on the forest locality and 53% of evaluated trees and shrubs were damaged by biting off shoots in the non-forest locality. Together, 262 woody plants belonging to 15 species were evaluated; the girth of tree trunks and stripped bark patches were measured. The most severely affected tree species, suffering from bark stripping and bitten-off sprouts, was Fraxinus excelsior; Acer campestre was also significantly affected. Results showed that woody plants provide a significant part of hoofed mammal nutrition (especially Capreolus capreolus and Cervus elaphus). The stripped bark dendromass per forested area of 625 m2 reached 3 m2. After the mild winter in 2014, the majority (93.7%) of previously affected Fraxinus excelsior trees in the forest locality had only old damages with renewed bark in different phases of regeneration. In the non-forest locality, 96% of young Fraxinus excelsior, damaged in the winter of 2013, shot up new sprouts. The mortality of affected trees was minimal (4−5%).