Philippine Journal of Science
154 (1): 1-11, February 2025
ISSN 0031 – 7683
Date Received: 02 Jul 2024

Noe P. Mendez, Fulgent P. Coritico, Maria Melanie M. Guiang, Florfe M. Acma, Mary Cor S. Salolog, and Victor B. Amoroso

The established 2-ha permanent plot of Balinsasayao Twin Lakes Natural Park (BTLNP) in Negros Oriental, the Philippines, is endowed with a variety of plants. Despite the importance of understory flowering plants, their species conservation status in the area remained undocumented, hindering effective monitoring. This study aimed to fill this knowledge gap by surveying the understory flowering plants within the 2-ha permanent plot of BTLNP. The findings will provide a foundation for conservation efforts, long-term monitoring, and future research, complementing existing studies on tagged tree species. This is the first report on the checklist of understory flowering plants in the 2-ha permanent plot of BTLNP. A plot sampling method, repeated transect walks, and opportunistic sampling along forest trails were used to record and determine the understory flowering plants in the area. A survey of understory flowering plants revealed 101 species, representing 74 genera and 33 families. The most abundant families were Rubiaceae (12%), Araceae and Orchidaceae (11% each), and Zingiberaceae (8%). Conservation assessments showed two threatened species: Hedychium philippinense (endangered) and Aeschynanthus truncatus (vulnerable). Notably, 18 species (0.37% of the Philippines’ endemic vascular flora) were found to be Philippine endemics. These understory plants provide crucial microhabitats and food sources for various fauna, highlighting their importance for ongoing monitoring and conservation efforts.