Phenology and productivity of saw palmetto (Serenoa repens) in a north Florida slash pine plantation

Phenological observations were used in conjunction with destructive sampling and measurements of plant cover to determine the aboveground seasonal dynamics, annual aboveground net primary production (ANPP), and responses to fertilizer applications of the rhizomatous, perennial, understory species, saw palmetto (Serenoa repens (Bartr.) Small), in a north-central Florida pine ecosystem. Phenology was not significantly affected by the fertilization. Flowering, fruiting, frond initiation, and frond mortality were all highly seasonal, but while flowering was consistent, fruiting occurred in only one of the three seasons studied. Turnover rates of plant biomass averaged 22% per year over the 2 years and treatments, resulting in ANPP values of 11-37 g·m-2 per year, with higher values on fertilized plots, which amounted to 1-3% of overstory ANPP.