Forestry reservation Dancu is situated in the bottom-grassland of the river Prut, occupies an area of 131 ha and, is attributed to the ecosystems constituted by willow (Salix alba), poplar (Populus alba). The researches done, during 2003-2006 period, had the target of performing the floristic and phytocoenotic composition and, elaborating optimal measures of biodiversity. As a result of the investigations were identified and registered 164 species of vascular plant, classified to 44 families and 120 genuses. 9 species of rare plants, being on high danger level, was determined. Floristic composition, from the biologic, ecologic, geographic, economic, caryologic point of view, was analyzed. 291 Vegetal community to 9 associations was attributed: Salicetum albae-fragilis Issler 1926; Populetum albae-Fraxinosum bessarabicum Borza 1937; Pruno spinosaeCrataegetum Soó 1931; Trifolio repenti-Lolietum Krippelova 1967; Agrostietum stoloniferae Burduja et. al. 1956; Sambucetum ebuli Felfödy 1942 (non Kaiser 1926); Lolio-Plantaginetum majoris (Linkola 1921) Berger. 1930; Arctio-Ballotetum nigrae Morariu 1943; Tanaceto-Artemisetum vulgaris Br-Bl. 1949.