Bidens amplissima, also known as the Vancouver Island beggarticks, is a wetland annual species in the sunflower family, Asteraceae that is listed as Special Concern in Canada and has a limited global range. More than 85% of known populations occur in southwestern British Columbia, with the remainder in northwestern Washington. Bidens amplissima occurs across a remarkable range of environmental conditions, both along the edges of freshwater ponds and under saline conditions in estuaries. Bidens amplissima displays a broad range of morphological variation and overlaps in morphological characteristics with two closely related and occurring species, B. cernua and B. tripartita.

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