Alpine plant species are thought to have limited phenotypic plasticity, but few data exist on forbs. We assessed plasticity in allocation of biomass to belowground and aboveground parts and to reproduction in 5 forb species from a 50-year-old disturbance and adjacent undisturbed areas in an alpine dry meadow. Three of the species, mostly those with variable numbers of stems per genet, increased in size in the disturbed areas. All 5 forbs showed very limited plasticity in allocation of biomass. Lack of phenotypic plasticity in these forbs may limit their ability to respond to future changes in environment.