Fire may stimulate flowering, branching, seed production and seedling establishment in two kangaroo paws (Haemodoraceae).
Abstract
Flowering (number of panicles) in the fire-tolerant kangaroo paws Macropidia fuliginosa [Anigozanthos fuliginosus] and Anigozanthos pulcherrimus was greatest in the year following fire, declining sharply to negligible levels after 5 years. The flowering response in A. pulcherrimus could be simulated in the absence of fire by applying fertilizer (Osmocote) and to a lesser extent by removing litter or clipping foliage. Seed production per panicle remained constant or increased over 2 successive years after fire, but seed production per unit area declined. Flowering culms, even when their panicles were removed, usually produced 2 axillary culms in the next season, while vegetative culms retained their apical dominance. Seedling establishment in M. fuliginosa was most likely during the first year after fire, attributable to enhanced germination of soil-stored seeds produced before the current fire. Despite producing 1-2 orders of magnitude more viable seeds per unit area than M. fuliginosa, seedling establishment by A. pulcherrimus was insignificant. Fire and other management practices could be used to manipulate flowering for the benefit of commercial flower picking and tourism but the population viability of other species might be threatened.