Population status, demography and habitat preferences of the threatened lipstick palm Cyrtostachys renda Blume in Kerumutan Reserve, Sumatra

Population status and demography of a population of the threatened lipstick palm Cyrtostachys renda in a peat swamp ecosystem of Kerumutan Reserve, Sumatra (one of the largest remaining populations) was documented at 16 different sites, covering a wide range of forest and habitat types, vegetation associations, and population sizes. Population sizes were dominated by suckers comprising 89% of the total population. Individuals with stem heights between 0 and 4 m (47.5%), stem diameters between 4 and 10 cm (82.0%), and leaf scar numbers between 0 and 60 (69.2%) dominated. Ages of individuals were estimated and used to fit a curvilinear relationship between age and stem height. Wild plants reach reproductive maturity within 25-30 years, or when they have stem heights in excess of 2.0 m, or when they have 15-25 leaf scars. They can survive more than 80 years. Cultivated plants appear to reproduce earlier and produce more seeds than wild plants. Individual growth was plant size-dependent with the adult stage being the most productive. Higher mortality was experienced by suckers, especially in continuously waterlogged conditions and locations with dense canopies. Sucker growth was faster than seedling growth, an adaptation that may allow the species to cope with periodically waterlogged conditions. Population abundances varied with habitat types; well-drained areas were the most suitable habitat. To conserve the most important remaining populations of the lipstick palm, it is crucial to protect well-drained sites in Kerumutan Reserve.