Does Slow Tree Growth Reduce Browsing Risk by Moose?

• Main Authors: Den Herder Michael L, T Ahv, Anainen Jorma, Niemela Pekka
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Alces alces; annual increment; boreal forest; deciduous trees; selective feeding
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.689.4680; http://eprints2008.lib.hokudai.ac.jp/dspace/bitstream/2115/22201/1/9%281%29_P9-15.pdf

Genotypic or phenotypic factors affect the growth of trees which can change the palatability of plants to herbivores. In a self-regenerating clear-cut forest stand in eastern Finland, we compared the growth of four boreal deciduous tree species that were browsed by moose with those which had been left unbrowsed. Diameter growth of young sapling trees of Betula pendula, Populus tremula, Salix caprea and Sorbus aucuparia was studied based on the width of the annual growth rings. Moderately browsed B. pendula showed higher radial growth than unbrowsed trees. Heavily browsed S. aucuparia and S. caprea initially had higher radial growth than unbrowsed trees although the radial growth increment decreased after consecutive years of repeated browsing. Moose browsing resulted in reduced height and stunted growth of the studied tree species. The results suggest that moose selects fast growing individuals and trees characterised by slow growth may have a higher probability of remaining unbrowsed.