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.
Salvinia molesta is a free floating aquatic fern that is highly invasive. When in the proper climate, S. molesta becomes a dense mat that interferes and alters with the aquatic ecosystem. Native to only four countries in South America, established non-native populations of S. molesta exist in Africa, Asia, Australia, Europe, North America and South America. It was first introduced to the United States as an ornamental plant. It is listed as a U.S. Federal Noxious Weed. A high climate match score and proof of invasion within the contiguous United States (and multiple other countries) allows for high certainty of this assessment. The overall risk assessment for Salvinia molesta is high.
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High Risk
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