Rocky slope landscapes are widely distributed on arid land mountains, where there are many restoration and forestation project sites. This study has surveyed the role of deep crevices and stone layers for supplying water to establish trees and shrubs on arid lands rocky slopes. The research was concentrated on the layers of Limestone, Granite and Andesite in central Iran. Thirty Transects, each 25 m long, were randomly laid out throughout the studied lithologic units. Correlation of vegetation cover percentage and abundance of trees were studied along with crack dimensions including width, depth, and length categorized into three classes; large, medium, and low sizes. Along those transects, the amount of EC, pH, organic materials, CaSO4, CaCO3, soil texture, N, P, K and soil moisture content in the cracks were also measured. The results showed significant differences (p < 0/05) among crack properties, vegetation cover and life forms in the study units. Also the vegetation cover and life forms have positive significant relationships with increase of crevice width as well as length and depth of each lithologic unit. The findings demonstrated that the inherent potential of limestone rocky slopes with deep layers is higher than other rocky units for restoration and afforestation in this arid region.

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