Species that are considered high risk have a well-documented history of invasiveness in at least one location globally, and a high or medium climate match to the contiguous United States.
The history of invasiveness is high. Azolla filiculoides is native to the western areas of North, Central, and South America. It has spread to every other continent except Antarctica and has had negative impacts in some locations. Climate match is 0.467, high. The overall match did include areas within the native range of A. filiculoides but eastern areas and around the Great Lakes basin (areas outside the native range) also had high climate matches. Due to the high history of invasiveness and the areas of high climate match outside of the native range in the United States, the overall risk assessment is high.
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High Risk
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