Impact of Livestock Grazing Pressure and Above-Ground Vegetational Changes on Yield of Caterpillar Mushroom (Ophiocordyceps sinensis)

Abstract

The perceptible decline in the yield of caterpillar mushroom or Yartsa Gunbu [ (Berk.) Sung, Sung, Hywel-Ophiocordyceps sinensis Jones & Spatafora], has taken place, primarily because of over-exploitation, and resultant habitat degradation. Does livestock grazing worsen the problem? This aspect vis-a-vis salient changes in the above-ground vegetation profile with increasing magnitude of grazing pressure remains the prime objective of the present study. Three sites- Janthri, Balmiya top, and Rukhiyan, were selected based on increasing order of magnitude of livestock grazing pressure, with the site- Janthri being treated as 'Control site', since it exhibited no grazing pressure. Care was taken, that all other parameters- slope aspects, altitudinal range, anthropogenic pressure, duration of grazing, etc, were relatively similar across the selected sites, with the only variable being the livestock grazing pressure. With 13 out of 21 palatable species and 3 out of 15 unpalatable species recorded as host plant species of the obligate host of Yartsa Gunbu, i.e., The perceptible changes in Thitarodes balmiya palatable plant species being replaced by non-palatable species with grazing intensity, is a cause of concern for the future viability of the host Thitarodes balmiya Thitarodes larva; as is so succinctly observed by the declining number of larval population size with grazing intensity, in the present study.