A harmful invasive plant species has been spotted in Ontario's waters once again this year, raising concerns among environmental officials over its impact on local ecosystems and recreational activities. Water soldier (Stratiotes aloides) is a perennial aquatic plant native to Europe and northwest Asia. Before it was regulated under Ontario's Invasive Species Act as a prohibited species, water soldier was sold for ornamental use in water gardens, which was most likely the pathway for its introduction to the wild. The pesky plant species poses multiple environmental and recreational concerns, as it forms dense mats of floating vegetation, which outcompete native plant species and reduce biodiversity. Typically submerged, water soldier becomes buoyant during the summer months.