Floristics study of Assadli - Rakhtian region in Bojnourd (North Khorassan province)

Flora study of Asadli-Rokhtian region with an area of ​​30,000 hectares in 25 km south of Bojnourd city located in North Khorasan province with an altitude of 1700-1900 m was performed. The aim of this study was to introduce and identify different species, medicinal plants and plants with low risk of extinction and rarity. The plants of the region were collected by survey method from May to August of 1991 and identified then handed over to the herbarium of Islamic Azad University Mashhad Branch (IAUM). The results of study showed 27 families and 61 genera including 69 species that Astragalus khoshjailensis from Fabaceae and Echinops khorassanicus from Asteraceae were reported as endemic elements for Iran and Convolvulus calyerti from Convolvulaceae, Sclerochorton haussknechtii from Apiaceae and Rosa webbiana from Rosaceae were rare species, Taraxacum hydrophilum belonginig to Asteraceae and Verbascum speciosum from Plantaginaceae  were reported as low risk of extinction from this region Also, 18 medicinal species belonging to the families Asteraceae, Brassicaceae, Boraginceae, Lamiaceae, Plantaginaceae, Salicaceae, Rosaceae, Papaveraceae and Resedaceae were introduced. The largest families in the studied region were Brassicaceae and Asteraceae with seven species, Fabaceae with six species, , Lamiaceae with five species, Liliaceae, Rosaceae and Papaveraceae with four species,. The life forms of specimens included, 36.23% therophytes, 34.78% hemicryptophytes, 13.04% geophytes, 10.14% chamaephytes, and 1.14% cryptophytes. The maximum and minimum chorotype percentage belonged to Mediterranean region with 1.44% and Irano-Turanian with 68.11. Regarding to the results, the high percentage of therophytes and hemicryptophytes indicated the cold and dryness of the region, the destruction of vegetation due to road construction, livestock grazing and the 10-year relative drought of the region.