Distribution pattern of Wild pear (Pyrus spp.) in the forests of Kermanshah province of Iran

Abstract In order to investigate the effect of Environmental factors for the propagation of wild pears (Pyrus spp.), after gathering some basic data, distribution limits of this specie in Kermanshah province was identified. Later on, the distribution areas were classified into three altitudinal ranges including (>1500, 1500-2000, < 2000m a.s.l.), four geographical directions including (North, South, West and East) and also different land forms including (Valley, Slope, Slope edge and Flat). To gather requisite information, some 1000m2 plots were established in each mentioned situation at least with three replications. Considering the density of the studied species (the presence of the desired tree in a group in a plot). Results showed that Slope form with west aspect At a range of 1500m to 2000 m a.s.l. prepared the best position for distribution of Pyrus spp.. Also Principle Component Analysis(PCA) of soil in Pyrus spp. provenance, positive effect of chemical elements such as: EC ,C,pH and negative effect of Caco3 on growth parameters of Pyrus spp. were indicated Mean while physic elements such as: Silt and Clay preferred positive effect on growth parameters at surface layer.