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.
Najas minor is a submerged aquatic plant with a far-reaching native range that includes countries within Africa, Europe, and Asia. Species within the Najas genus are morphologically similar, which can make identification of the various species somewhat difficult. Distribution of established populations beyond this native range includes thirty-six states within the contiguous United States and two locations within Canada. Establishment often leads to dense monocultures, reduction of water discharge capacity, and compromised habitat. Negative impacts to humans can include interference with recreational activity such as swimming, boating, and fishing, as well as reduced aesthetic value of waters. Climate match within the contiguous United States was very high, with high scores for all states. Given all factors, the overall risk of Najas minor within the contiguous United States is high.
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High Risk
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