To investigate cadmium (Cd) behavior in soil due to vehicle traffic under rosemary and grass plants in three urban areas of Mashhad, this study was carried out in a completely randomized design (factorial). In the studied sites, first 30 cm of upper soil was replaced with a new superficial soil (along with compost and cow manure) as control, prior to soil contamination. In four seasons, Sampling from soil, shoots and roots of Rosemary and Grass plants was taken and Cd concentrations measured. The results showed that the average Cd concentration in control soil (without cultivation) in two sites: 1) 100 meter (Mosalla complex) sites, and (2) Imam Reza bus terminal during the experiment period increased significantly from spring to winter season, while on third site: (3) Botanical Garden, soil Cd was almost constant. The highest soil Cd concentration was noted in winter, while in three sites, the soil Cd concentration decreased. The Cd concentration of aerial parts each plants was significantly different during the seasons. The plant Cd concentration decreased during the spring and summer, while it increased in autumn and winter season. It is concluded that rosemary cultivation in urban parks is a good candidate for Cd phytostabilization.

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