The Recent History of Subalpine Krummholz Pines (Pinus sylvestris) in the Swedish Scandes

Abstract

This paper accounts for photographic surveys of stunted old-growth krummholz pines (Pinus sylvestris) in the context of climate change and variability since the late 1970s and early 1980s. The study was conducted within the alpine-tundra ecotone of the southern Swedish Scandes. The life-histories of pines with this shrubby and stunted growth mode are little studied. They may play some role as dispersal nuclei, contributing to elevational treeline rise in cases of future climate warming. In contrast to earlier assumptions, it now appears that pines, growing in open spaces of the subalpine birch forest belt, may regenerate vegetatively by layering, enabling surprisingly old ages. Having survived the harsh centuries of the Little Age, they have recently attained tree stature and started to produce offspring in their near vicinity. Thereby they contribute to ongoing pine treeline rise and transformation of the forest-alpine tundra ecotone.