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Marls form the weakest part of geological formations that are highly erosive. Sustainable action in soil stabilization is biological operations. The dense cover of Pasture rangeland species in some areas of Marl has caused soil stability in these areas. It seems that some of the physical and chemical properties of marls play role in creating such a cover in areas covered by marl formations. This research was conducted with the aim of carefully and systematically study of plant species and determining their site needs and protective role in three eastern, southern and western regions in Ilam city. For this, 30 marl deposit samples were collected from three ranges and physical and chemical tests were performed on its. Botanical studies were also performed using repeated field visits and plot establishing at 180 locations, and plant samples were identified after transfer to herbarium. Results showed that, giving the stratigraphy of Marl Gorpi, Pabdeh, Gachsaran and Aghajari formations, sediments of these three regions in terms of salinity (EC), specific gravity (BD), sodium (Na +) and Soil saturation percentage (SP) and some physical parameters such as gravel, sand and silt particles have significant differences which R2 has shown significant statistical effect of soil physical and chemical properties on plant cover type. This difference could be as one of the effective factors in the diversity and difference of vegetation grown in three areas. In this research, the site need of plant species compatible with marl type and soil protection role of each of them in eastern, western and southern regions of Ilam city has been introduced.