About Bidens L. species on the Milyatinskoye water reservoir sides in Kaluga region

There were researched morphological, ecological and formational characteristics of Bidens L. species on the Milyatinskoe water reservoir sides in Kaluga region: natural spesies B. cernua L. and B. tripartita L. and alien species B. connata Muehl. ex Willd. We revealed the diagnostic characteristics of these species, and we made prognosis of widening area of B. connata in this district.