Leaf Shedding Phenology of Ficus Glauca, Terminalia Catappa, and Cassia Fistula

Abstract

Phenology is a study that explores periodic tree lifecycle events and how those events are influenced by seasonal climatic variation. This study aimed to observe the leaf-shedding period of three commonly found deciduous tree species in the tropics: Ficus glauca, Terminalia catappa, and Cassia fistula; and to analyze the climatic driving factors to trees' phenological phases. A field survey was conducted to observe the samples, each species consisted of five trees. The survey was conducted weekly from September 2016 to February 2017 in Bogor City and Regency. It was found that F. glauca shed its leaves more than once a year. The canopy coverage reached its lowest in February (65.7% coverage). Leaf shedding process in T. catappa reached its peak in January (83.7% coverage), meanwhile, C. fistula's shedding period is suspected to happen before September because its canopy coverage kept increasing during the survey (69.7%-95.1% coverage). The climatic factor that significantly affected F. glauca was the previous month's rainfall. When the rainfall in the previous month decreases, the leaf shedding increases. T. catappa and C. fistula were significantly affected by day length. For T. catappa, when day length decreases, the leaf shedding increases. Meanwhile, for C. fistula, when day length increases, it is shedding its leaves. Leaf phenology of deciduous trees in a tropical climate was affected by different climatic factors depending on their species.