Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
Comments: Thousands of populations are extant rangewide. Many hundreds, and probably thousands, of populations are known from Ontario, where it is usually rather local and seldom in large dense populations (Michael Oldham pers. comm.). It is common in eastern Kentucky, becoming infrequent to rare westward (Kentucky Natural Heritage Program). It is common in New York, with hundreds of populations across the state (New York Natural Heritage Program). A single population is reported from Kansas (Kansas Natural Features Inventory). It is widespread around the entire state of Michigan (Michigan Natural Features Inventory). It is reportedly not common in Indiana, and does not form large populations there (Indiana Natural Heritage Data Center). Sixty extant populations are reported from Delaware (Delaware Natural Heritage Program). It is common in Maine, and is reported from all counties in the state (Maine Natural Areas Program). Eight occurrences are known for Nebraska that have been observed since 1970 (Nebraska Natural Heritage Program). Two (possibly three) occurrences with not more than 10 individuals each are known from Mississippi where this species is ranked S1? (Mississippi Natural Heritage Program). One occurrence record is currently on file for Colorado and other historical occurrences are also reported (Weber and Wittmann 1996b). At least 3 occurrences are known from Manitoba (Manitoba Conservation Data Centre). The plant is not rare in New Hampshire (New Hampshire Natural Heritage Inventory).