Abstract
Treeline is considered as a transitional zone between boreal forest (taiga) and Arctic tundra. Its dynamic landscape structure is composed of isolated tree and shrub patches.
Different life strategies and ecological adaptations of both life forms determine the diversity of transitional sites that are sensitive to biotic, (micro-)climatic, and also human influence. Growth plasticity of common juniper (Juniperus communis) - the most widespread woody species - is described in detail to show its potential to adjust growth dynamics to local specific climatic conditions.