CO2 effects on reproduction versus vegetative growth

Increased atmospheric CO₂ concentrations may affect competition for resources between reproduction and shoot growth in forest species. Han et al. examine mature beech (Fagus sylvatica) trees in masting and non-masting years with or without long-term CO₂ enrichment and find that a reduction in shoot growth associated with masting is not observed under elevated CO₂. Competition for resources is therefore reduced and rising atmospheric CO₂ concentrations shift the balance of allocation witin the shoots.