Reproductive strategies of six perennial plant species in relation to a successional series

Abstract

Data are presented on the phenology of dry weight allocation of plant tissue to major component parts for six herbaceous perennials, in relation to a successional sequence. Individual reproductive effort is shown to be constant throughout the succession. Reproductive effort at the population level however is shown to be highest in an early successional quarry site and lowest in an ungrazed grassland site. Populations from the successionally more advanced scrub site generally show a level of reproductive effort between the other two. Significant intra-specific differences between populations from the three sites are demonstrated for mean total plant dry weight, time of anthesis, leaf area and stem length. These are interpreted as plastic responses to environmental variables and the level of competition. Leaf palatability experiments show that leaves taken from different parts of the succession are not different in their palatability to a generalised herbivore.