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Divergent Responses Of Cryptic Invasive Watermilfoil To Treatment With Auxinic Herbicides In A Large Michigan Lake, Syndell R. Parks

Masters Theses

Invasive plants are a major concern for environmental managers. Cryptic invasive taxa present additional challenges because of their potential to respond differently to management efforts. Invasive Eurasian watermilfoil (Myriophyllum spicatum) and hybrid watermilfoil (Myriophyllum spicatum x Myriophyllum sibiricum) cannot be reliably distinguished based on morphological characters and are therefore cryptic taxa. Laboratory studies show that on average, hybrid watermilfoil grows faster, branches more, and is less responsive to standard control measures developed for Eurasian watermilfoil. These laboratory results predict less effective control of hybrid watermilfoil in mixed populations treated uniformly with one of these control measures. However, to date there …