“…Solidago canadensis L., commonly known as Canadian goldenrod, native to N. America is widely spread throughout Europe, Asia (China, Russia, Japan, and Taiwan), Australia and N. Zealand, where it is considered an aggressive invasive weed [ 2 , 3 , 4 ]. The taxon is highly diverse, prone to hybridization, and therefore characterized by extensive polyploidy [ 1 , 2 , 5 , 6 , 7 , 8 ]. It is known that two N. American invasive species, S. canadensis and S. gigantea Aiton, can hybridize with the European native S. virgaurea L. producing the hybrids S. × niederederi Khek (hybrid between S. canadensis and S. virgaurea ) and S. × snarskisii (hybrid between S. gigantea and S. virgaurea ) [ 5 , 6 , 7 , 8 , 9 ].…”