Foliar chemistry and leaf herbivory on mount Bloomfield, Palawan, Philippines

Abstract

Summary Mount Bloomfield has a range of vegetation types on non-ultramafic and ultramafic soils. We report here foliar chemical analyses for N, P, K, Na, Ca, Mg, AI, B, Co, Cr, Cu, Fe, Mo, Mn, Ni, Si, Zn made on a large number of tree species. The most important results were: the notably high calcium in the ultramafic forest leaves, the occurrence of an aluminium accumulating species and two nickel accumulators on the ultramafic soils. Measurements of herbivory by the leaf-hole method showed that the percentage leaf area consumed by herbivores was similar in all the plots but the actual leaf area consumed was greater in the non-ultramafic forest because this had the largest leaves. There was no relationship between herbivory, and any of the leaf mineral elements investigated. Even the accumulating species were attacked by herbivores, of which the gall-formers and leaf-miners must be tolerant of high element concentrations, since the whole of their juvenile existence is in the leaf tissue.