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For analyzing the effects of forest litter and slope aspect on soil properties eight soil samples were collected at a depth of 0-10 cm near (i.e.,beneath the crown) and away from (i.e.,not influenced by crown) five Persian turpentine trees each on a north and a south slope at the same elevation in a Zagros forest,Iran.The litter beneath tree crowns and slope exposure were found to have significant interactive effects on C,N,P,K,and electrical conductivity of the soils,however,Ca,Mg and the soil pH were not significantly influenced by these factors.The soil beneath the crowns was enriched in cations compared to more distal positions.Generally,Persian turpentine trees have positive impacts on soil properties in the forest.Degrading or killing these trees by sap extraction,extreme grazing,cutting,fire and expansion of agriculture will lead to significant losses in soil fertility and increases in soil erosion.