Previous studies have shown that seeds of some rangeland plant species are dormant at maturity. Seed dormancy is a characteristic that can both help maximize the probability of seedling establishment and spread the risk of recruitment failure across years. In order to investigate the germination properties and seed dormancy of 26 rangeland species (from poaceae, leguminoseae, Caryophyllaceae, Zygophyllaceae, Apiaceae, Convolvulaceae, Rosaceae, Caryophyllaceae, Chenopodiaceae and Asteraceae families) collected from Northern Khorasan province, an experiment was conducted in the Faculty of Agriculture, Ferdowsi University of Mashhad in autumn 2008. The experiment was conducted in two sets which were preliminary stage with distilled water to evaluate seed germination of the species and some treatment for dormant seeds as second stage of the experiment. Treatments included sterilization for infected species, scarification using sand papers with different toughness, Light/darkness period, Removing covering structure, KNO3 and temperature for breaking seed dormancy. Results showed that seeds of family of Poaceae had no dormancy while seeds of species from family of Leguminoseae were dormant. Seed dormancy breaking treatments had positive effects on germination of seeds of other species, too.

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