Early Growth of 11 Native and Three Alien Tree Species in Northeastern Mindanao, Philippines

Early growth performances of 11 native tree species were investigated in three different sites in Mindanao, Philippines, to evaluate their adaptability and potential for plantation development. Three alien species were added to assess how native species could potentially compete with these alien species based on survival rate, diameter growth rate (DGR), and height growth rate (HGR). A year after planting, the native species common to all sites that obtained >80% survival rate were Casuarina equisetifolia L. Alstonia macrophylla Wall. ex. G.Don., Alstonia scholaris (L.) R.Br., and Parkia javanica (Lam.) Merr. and were comparable to an alien species Acacia mangium Willd. The species with the lowest survival rate (30%) across all sites was Duabanga moluccana Blume. Native species P. javanica, Eucalyptus deglupta Blume, and A. macrophylla all had a DGR of 34 mm year−1 and were comparable with the alien species Schizolobium parahyba (Vell.) S.F.Blake with 38 mm year−1. However, the HGR of native species E. deglupta (245 cm year−1) and Melia dubia Cav. (230 cm year−1) were higher than an alien species S. parahyba (222 cm year−1). No native species can compete with the DGR (52 mm year−1) and HGR (384 cm year−1) of A. mangium. Rainfall significantly explained 13%–97% of DGR, HGR and survival rate of >70% of the species while air temperature explained about 17%–96% of the variations of similar variables. This early assessment provides a strong basis to better predict the early performances of native species in the Philippines. Through this, appropriate silvicultural intervention can be recommended towards improving the growth and survival of the native seedlings as alternative industrial tree plantation species in the country.