Medical Definition of Facultative species
1.
Species that can occur both in wetlands and uplands, there are three subcategories of facultative species:
1. Facultative wetland plants (FACW) that usually occur in wetlands (estimated probability 67-99%), but occasionally are found in nonwetlands.
2. Facultative plants (FAC) that are equally likely to occur in wetlands or nonwetlands (estimated probability 34-66%).
3. Facultative upland plants (FACU) that usually occur in nonwetlands (estimated probability 67-99%), but occasionally are found in wetlands (estimated probability (1-33%).
(09 Oct 1997)
Lexicographical Neighbors of Facultative Species
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