Pre-emergence processes limit seedling recruitment in two direct seeded Acacia spp.

Abstract

The use of direct seeding for revegetation often results in poor recruitment outcomes. For many species, it is unclear where recruitment bottlenecks occur in the transitions between early life-history stages and how soil moisture conditions affect these bottlenecks. Thus, we asked: (1) which life-history stage transitions are most limiting to seedling recruitment? and (2) how do soil moisture levels affect recruitment? Using a field-based trial, we quantified the recruitment process from a seed to seedling for two woody Acacia species. Using a novel technique, in which seeds were confined to germination caches (small baskets), along with the use of germination bags, we assessed pre-emergence..