Regeneration traits in the weakly serotinous obligate seeder Leucadendron xanthoconus (Proteaceae)

Experimental work with seed of the mountain fynbos proteoid Leucadendron xanthoconus (Kuntze) K. Schum. showed that this obligate post-fire reseeder stores its current seed crop in cones capable of resisting intense heat. Nevertheless, seed recovered from non-treated cones of this dioecous species germinated readily in the absence of any influence from fire, and in some cases remained viable in the soil for two intervening dry summer periods. It was also shown that seeds buried at 40mm depth in native mountain fynbos soil germinated less readily than those at depths of 20mm and less. I suggest that some of the observed germination traits are relictual, pre-dating serotiny as an adaptation to fire-driven systems, but that their presence might imply functional value for long-term survival of populations