Compensatory growth of Euphorbia peplus regenerating from a bud bank

Abstract

Tolerance to very severe disturbance by the annual herb Euphorbia peplus L. was examined. We explored the role of disturbance timing, competition, and site productivity on the performance of disturbed plants. Ninety-three percent of disturbed plants survived following disturbance 14 d after plant emergence, whereas only 48% of disturbed plants survived disturbance 42 d after emergence. Early disturbed plants compensated for biomass loss and had higher fecundity than undisturbed plants, but this was not the case for plants that were disturbed at later times following emergence. Field assessment revealed that disturbed plants were, in general, of the same height as undisturbed plants, even under competition. Undisturbed plants had very conservative architecture across various conditions (competition and nutrients), whereas disturbed plants had more branched architecture under moderate competition and nutrient availability. Accordingly, we suggest that E. peplus utilizes a bet-hedging strategy where adventitious meristems are reserved for regrowth after a severe disturbance event that removes all dormant axillary meristems. Moreover, we propose that the tolerance to disturbance in short-lived species could play an important role in the ecology of disturbed communities. Finally, the tolerance to disturbance could be one of the prerequisites of invasibility of E. peplus in non-native ranges. We also speculate about the potential costs and benefits related with the tolerance to disturbance in short-lived species and about a mechanical control of E. peplus in invaded ranges.