Tree Species Association in the Churiya Hills of Eastern Nepal

  • G. P. Joshi Amrit Science Campus, Tribhuvan University, Lainchaul; Kathmandu
  • D. R. Bhuju Royal Nepal Academy of Science and Technology, GPO Box 3323, Kathmandu

Abstract

Association of tree species was evaluated for the Churiya hills in eastern Nepal extending about 105km from Saptakoshi river to Mechi river. In a total of 64 sampling sites, the predominating deciduous broad-leaved species Shorea robusta showed association with one or more species at 49 sites. The species was found growing in combination with 46 types of tree species in the area. Similarly Lagerstroemia parvijlora and Terminalia alata were found growing with 44 and 42 tree species respectively. The highest association was found between S. robusta and T alata with a frequency of 42.2% followed by S. robusta and L. parvijlora with a frequency of 35.9%. The association of the tree species showed a relationship with altitudinal variation. The association of S. robusta with Schima wallichii was in an increasing trend while that with L. parvijlora was in a decreasing trend along the elevation range from 200m to 1,000m asl. S. wallichii was found up to 300 m, a lowest record of its occurance in Nepal.