Abstract: Invasive species pose a serious threat to native ecosystems and their biodiversity, and cause considerable economic loss to the regions they invade. In the case of Canada goldenrod (Solidago canadensis L.) (Compositae), a long-lived perennial plant native to North America, it was initially introduced as an ornamental plant to Shanghai in 1935, it then escaped into the wild and it is now spreading rapidly in China, especially in eastern China. We here describe briefly this species in relation to invasion biology. S. canadensis is actually a Canada-goldenrod complex that consists of at least six subspecies and varieties. S. canadensis has great reproductive capacity (through both seed production and clonal growth) and high genetic variation, both of which contribute to its great invasiveness. S. canadensis may outcompete or allelopathically exclude native plant species, resulting in monospecific stands with concomitant loss of plant and insect diversity, and ultimately alteration in ecosystem functioning. Lack of natural enemies in the invaded ecosystems makes this species highly invasive. Abiotic factors such as niche opportunities created by habitat disturbance and human activities, and nitrogen deposition, can promote S. canadensis’ establishment and spread through seed dispersal and vegetative structures. In addition, the species’ capacity for early season emergence and growth, rapid clonal growth, wide physiological tolerance, and high architectural plasticity make the species highly aggressive under a wide range of ecological conditions. Although commonly used control methods of weeds may also be suitable for S. canadensis, minimising its seed production seems to be critical to its effective control, which requires that all the control measures be taken during its vegetative growth.

Key words: Canada goldenrod (Solidago canadensis), control, invasion mechanism, invasive alien species, sexual reproduction