Mean maximum net CO₂ uptake rate obtained in fall (open symbols) and summer (closed symbols) and specific leaf area (SLA) with respect to elevation in the timberline ecotone at Mt Patscherkofel between 1950 and 2 175 m a.s.l. Points were fit by linear regression: mean maximum net CO₂ uptake rate fall: y = 0.0057x − 7.9, r² = 0.98; mean maximum net CO₂ uptake rate summer: y = 0.0021x + 1.1, r² = 0.97; SLA: y = − 0.0037x + 115, r² = 0.82.