Recruitment variability in the resprouting shrub Banksia attenuata and non-sprouting congeners in the northern sandplain heaths of southwestern Australia

Seed production, seed availability, seedling recruitment and water relations (xylem pressure potential, stomatal conductance) in Banksia attenuata were studied from the base (swale) to the crests of a sandy dune system in a fire-prone scrub-heathland. Number of seedlings established per parent in 1986 (0-3 years after fire) ranged from 0.09 on a dune crest to 3.92 on a dune slope and 3.28 in the swale. Seedling survival was negatively correlated with relative elevation of sites so that by 1990 number of seedlings per parent was greatest in the swale (1.94) and zero on the dune crests. Non-sprouting congeners showed good recruitment at all sites. Population maintenance on dune crests and coexistence with non-sprouter congeners is primarily due to the high adult survival rate which enables the population to survive long periods which are unfavourable for recruitment