An Inventory of the Aquatic and Subaquatic Plants in SASKWater Canals in Central Saskatchewan, Canada, Before and After the Application of the Herbicide Magnacide

Résumé

This study focuses on the floristic composition of aquatic and semi-aquatic plants in the SASKWater canal system and their potential effect on irrigation systems. A checklist, evaluation, and synthesis of the species identified in this survey before and after the application of the herbicide Magnacide are provided, in addition to a brief discussion of the environmental effects of Magnacide. Thirty-three species in 26 genera within 20 plant families were identified. Two unidentified green algae were also collected. Common aquatics (i.e., green algae, Potamogeton spp., Alisma gramineum, A. plantago-aquatica, Ceratophyllum demersum, and Myriophyllum sibiricum) combined with debris from terrestrial plants were the primary contributors to blockage of irrigation drains. In general, the concentration of Magnacide used in this study had a minor effect on aquatic plant diversity, but effectively reduced plant density. However, the long-term effects of pesticides on the surrounding aquatic and terrestrial environments of the SASKWater irrigation system are unknown.