Asteraceae/Compositae (Aster/Composit Family) Synonym(s): Canada Goldenrod, Canadian Goldenrod, Tall Goldenrod, Giant Goldenrod Base Flower Color: YellowReproductive Phenology: Aug, Sept, OctNotes: Although it and other Goldenrods are commonly blamed for hay fever, this discomfort is usually caused by pollen from Ragweed (Ambrosia spp.) that blooms at the same time. For more information about this plant, Click Here.