Dendrometer data of the tall shrub Alnus alnobetula at the alpine treeline

Green alder (Alnus alnobetula (Ehrh.) K. Koch) is a tall, multi-stemmed deciduous shrub widespread in the Central European Alps across the treeline ecotone. On Mt. Patscherkofel (2246 m a.s.l.; Tyrol, Austria; 47°12’31” N, 11°27’38” E) three A. alnobetula stands were selected and radial stem growth was continuously recorded during 2022–2024 by point dendrometers (n=16–21 dendrometer records per year). The plots included a site situated somewhat below the forestline at 1940 m a.s.l. (FL) and two other sites located close to the treeline. The latter differed in terms of contrasting environmental conditions with regard to the duration of snow cover, i.e., one site facing south-east (TR-S, 2140 m a.s.l.) and one facing north (TR-N, 2150 m a.s.l.). The age of selected A. alnobetula stands within the treeline ecotone ranged from 20 to 30 years. The data file (data_environm_dendrom.xlsx) contains raw dendrometer data of all samples and environmental records during the study period 2022-2024 at all plots within the treeline ecotone.