Threat of potential bioinvasion in a natural forest in Ifugao [Philippines]

Enumeration of a natural forest (muyong) coupled to rice terraces (payoh) in Poitan, Banaue, Ifugao resulted in the recognition of three types of vegetation after raw data from 22 plots composed of importance values of three species were analyzed and subjected to Polar Ordination Analysis and Principal Component Analysis. The three clusters were named according to their most dominant species, namely Pinus kesiya cluster, Vaccinium whitfordii clusters were named according to their most dominant species, namely Pinus kesiya cluster, Vaccinium whitfordii cluster and Clethra tomentella-Swietenia macrophylla cluster. Shannon-Wiener Diversity Indices (H)of 22 plots were determined and results show that Pinus plots had lower H values compared with both Vaccinium and Clethra-Swietenia H values. This is attributed to the greater shade in Pinus plots as the pine trees there are large with bigger crowns. In the other clusters, more light reaches the forest floor allowing and diverse recruitment of light-demanding tree taxa. Two of the three alien tree taxa, Large Leaf Mahogany Swietenia macrophylla and Yemane Gmelina arborea, are definitely introduced as their locations are only near cemented trails, nowhere, else. However, the presence of a third alien tree species, Japanese Alder Alnus japonica, in the muyong is uncertain if it was also purposely introduced as their locations are only near cemented trails, nowhere else. However, the presence of a third alien tree species, Japanese Alder Alnus japonica, in the muyong is uncertain if it was also purposely introduced in the forest subtypes, even away from the cemented trail. Visually, this light-demanding wind-dispersed temperate. Asian taxon is randomly numerous in open areas, thickets and secondary forests of the Cordillera highlands. The present study and survey will also be replicated in Barangay [village] Amanagad amd Kinakin, Banaue, Ifugao.