Status of the Red-Listed Plant Species, Smilax wightii A. DC. in Nilgiri Biosphere Reserve, the Western Ghats, India

Abstract

The rare endemic plant, Smilax wightii, is generally distributed in shola forests at high altitudes in Nilgiri Biosphere Reserve, the Western Ghats, southern India. To determine the ecological status of the species, we surveyed 11 major shola forests in that region. S. wightii has a limited distribution in all sholas (frequency value of < 13%). The density of the species is generally around <TEX>$15/100\;m^2$</TEX> in the sholas except in Thiashola where it occurred at a density of 40 individuals/<TEX>$100\;m^2$</TEX>. The density of S. wightii was generally greater in the margins of the shoals, while the interior forests contained fewer individuals per unit area. The basal cover occupied by this species ranged between 2246 and <TEX>$3144\;mm^2/100\;m^2$</TEX>. The importance value index for S. wightii was >2 in all shoals, which indicates that the species occupies an important position in the lower stratum of shola forests of Nilgiri Biosphere Reserve.