In order determine forage quality which is one of the most fundamental prerequisites for better management of rangeland leading to higher animal performance this experiment was carried out. Five species of vegetation namely; Agropyron tauri, Ag.trichophorum, Bromus tom en tellus, Festuca avina, Hordeum bulbosum were selected to investigate effects of climate, soil as wel1 as phenological stage on forage quality. Samples were collected from] 8 vegetation communities of 8 climate zones and in three phenological stages of vegattive, flowering and seed production. Soil samples were ana lysed to determine N,P, K, and organic material. Variance analysis and cluster analysis were applied to data. According to the results; forage quality of species was significantly differences analysis among crude protein percentages of species and phenological stages in different climatic zones. There was not a significant difference
observed between ADF% and NDF%, and phenological stages in different climatic zones. The results of variance analysis showed that amount ofN,P,K and organic matter differed significantly in unique climatic zones. The results of cluster analysis indicated that effect
of climatic condition is more serious on forage quality than the effect of soH characteristic..
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