Intra- and interpopulation variability of Solidago canadensis L. s. l. in Belarus

The study of the variability of 22 morphological characters in 5 populations of Solidago canadensis L. s. l., growing in the city of Minsk and its environs, was carried out. Comparison of the obtained data with previously published information on the nature and range of variability of the North American taxa Solidago subsect. Triplinerviae showed that plants growing on the territory of the Republic of Belarus cannot be unambiguously assigned to any of the North American species by the combination of morphological characters. Compared to North American taxa, the plants of the studied populations have a significantly more powerful habitus (a large average plant height, longer and in many populations broader mid stem leaves, most often a larger inflorescence), intermediate in comparison with S. canadensis s. str. and S. altissima s. str. and significantly different from both North American species, the length of involucres and the length of tubular flowers, significantly longer outer phyllaries, shorter straps of ray florets, larger ovaries of ray florets, but their shorter pappus, a significantly smaller number of disc florets. The disc florets have significantly larger teeth compared to S. canadensis s. str. and S. altissima s. str. The data obtained confirm the point of view of Hildemar Scholz, according to which the invasive goldenrod, which is currently widely distributed throughout Europe, are of European origin. Most likely, they are either stabilized hybrids that arose during breeding due to the crossing of several North American species, or arose as a result of spontaneous mutation and further selection under natural conditions.