Canopy-stored seed reserves (serotiny) in Cape Proteaceae

Many species in several genera of Cape Proteaceae retain seeds in serotinous cones for a number of years after they have matured. This study is a report on the contribution of canopy-stored seeds to viable seed reserves. Cone retention patterns were censused for most of the common serotinous species in southern Cape fynbos and for Protea nitida, a non-serotinous species. Germination trials were conducted in an open nursery to determine age-related variation in seed viability. Significant numbers of viable seeds were stored for a year or more in all the serotinous species studied but the contribution of two-year and older cones was small in Protea repens and Leucadendron conicum.These results suggest that seasonal variation in pre-burn seed reserves is not sufficient cause for recruitment failure in stands of serotinous Proteaceae burnt in winter or spring. Adaptive suites of characteristics associated with serotiny are described and contrasted with non-serotinous species of fynbos Proteaceae