Canopy dieback in the upper montane rain forests of Sri Lanka

In 1978 a patch of dying upper montane rain forest had been observed on the slope of Thotupolakanda above Horton Plains. Patches in the upper montane rain forests of Sri Lanka were also recorded in 1980/81. All these sites were on windswept western slopes and ridges with stunted tree growth and shallow soil. From 1971 to 1983 Sri Lanka experienced some exceptionally dry years. The severe droughts of 1976 might have cause or “triggered” that dieback. After heavy rains between 1983 and 1986, these forests showed signs of recovery. Some trees had survived and sprouted again. Tree saplings were found, but regeneration was very low and further impeded by serious frost in February 1986. The influence of drought and frost clearly indicates the vulnerability of the stunted upper montane rain forest in the highest and wind-exposed regions of Sri Lanka.