Species of the genus Ambrosia L. (Asteraceae) in the Ivanovo region

The article deals with the peculiarities of distribution of species of the genus Ambrosia L. (Asteraceae) in Ivanovo region. On the basis of researches and observations in the city of Ivanovo and different districts of Ivanovo region it was noted that Ambrosia artemisiifolia is known in the region since 1985 and is widely distributed, it is found in 17 localities in the territory of the region, in 12 squares in Ivanovo. Ambrosia trifida appeared in the region in 1992 and is known in 4 localities of the region and in 2 squares in Ivanovo. It was found that these species are spread by different ways, mainly from southern regions of Russia and occur only in disturbed habitats. So far we cannot speak about successful naturalization of these species in the region, although in some years the plants are able to undergo a full life cycle, bloom abundantly and produce seeds. At the present stage, the spread of A. artemisiifolia and A. trifida in Ivanovo region can be controlled by timely identification of growing sites and the organization of measures to eliminate them.