Environmental influences on growth and reproductive maturation of a keystone forest tree: Implications for obligate seeder susceptibility to frequent fire

Our results show that environmental factors influence the primary juvenile period of a keystone obligate seeder, in turn affecting the time taken for a population to develop a reproductively viable seed amount of seed. Reduced fire return intervals may therefore constrain the species' realised niche (and geographic distribution) to areas where it can tolerate shorter fire return intervals due to faster growth and maturation. We suggest that populations of obligate seeders that reach reproductive viability faster are thus more likely to persist when exposed to multiple fires in short succession. Intra-stand variation in seed crops suggests that selection could also act on rapidly-maturing individuals, resulting in some populations exhibiting high levels of precocious reproductive activity.