The goal of the present research is to point out some morphological features of «Siberian Balsamic Poplar» and specify its systemic position, and to study hybridization between Populus nigra and «Siberian Balsamic Poplar» in Novosibirsk in the natural and ruderal habitats. Identification of hybrids has been done by morphological features. The following features have been taken into account: the degree of severity of the groove on the petioles of leaves, presence or absence of petiolescence, the presence of glands in the base of leaf plates, color and form of the leaf plates. On the basis of analysis of morphological features the paper shows that «Siberian Balsamic Poplar» in Novosibirsk is an inter-sectional hybrid of black and balsamic poplars and corresponds to the description of P.×sibirica G. Krylov et Grig. ex Skvortsov. A wide use of this cultivar in the green construction and protective afforestation created conditions for neat contact with the local aboriginal type P..nigra. At the present time on the premises of Novosibirsk there is a mass hybridization of P.×sibirica and P..nigra in the Obfloodplain, on the shore of Ob sea and waste grounds. According to morphological features hybrids can occupy an intermediate position between the parent taxa. Such hybrids have a pronounced but interrupted groove, pubescent petioles, glands in the base of the leaf blade. In hybrids evading to P..nigra, the petioles are slightly flattened, often pubescent and have a slightly noticeable groove. In addition, these specimens have a more rounded, rather than deltoid or diamond-shaped, as in P.. nigra, the outline of the base of the leaf blade. The invasive activity of hybrids can lead to disruption of the functioning of natural ecosystems.