The cause of bark stripping of young plantation trees

Abstract

Herbivorous mammals, from small voles to large ungulates, strip and eat the bark of young plantation trees. They do this most frequently at times when sources of protein food that can support their reproduction and lactation are in short supply. Furthermore, they preferentially attack—often repeatedly—trees that have experienced some form of environmental stress, leaving neighbouring trees untouched. Such stressed trees carry higher levels of amino acids in their phloem. These facts, coupled with the similarly timed and selective harvesting of bark phloem by some Australia marsupials and Northern Hemisphere woodpeckers indicate that it is the trees’ protein-enriched phloem that the bark strippers are seeking.