REDISCOVERY OF Baptisia tinctoria (L.) R. BROWN (FABACEAE) IN ILLINOIS

Castanea, Sep 2004 by Carroll, Connie J

REDISCOVERY OF Baptisia tinctoria (L.) R. BROWN (FABACEAE) IN ILLINOIS-Thought to have been long extirpated from the state of Illinois, small scattered populations of Baptisia tinctoria (L.) R. Brown were recently discovered in sand communities in the southeastern corner of Kankakee County.

Baptisia tinctoria (yellow wild indigo) ranges across 25 states in the eastern and southeastern United States as well as Ontario, Canada (Gleason and Cronquist 1991, United States Department of Agriculture, Natural Resources Conservation Service 2002). It is a perennial forb that prefers dry, sterile, and sandy soils, often in dry, open woodlands, savannas, or clearings (Larisey 1940, Fernald 1950, Gleason and Cronquist 1991, Isely 1998). Considered common throughout most of its range, B. tinctoria is understandably less common near the limits of its distribution and is listed as endangered in Maine, threatened in Kentucky (Kentucky State Nature Preserves Commission 2001, United States Department of Agriculture, Natural Resources Conservation Service 2002), on the watch list in Indiana (Yatskievych 2000, M. Homoya, pers. comm.), and of special concern in Iowa (Iowa Administrative Code 1999) and Wisconsin (Wisconsin Department of Natural Resources 2002) where its presence was documented for the first time in 1969 (Cochrane 1976). Minnesota holds one vouchered specimen from the late 1800's. During the past decade, B. tinctoria has experienced some declines in populations due to increases in commercial demands for its medicinal properties, thereby warranting its inclusion on a list of United States medicinal plant species that have been designated as 'priorities for further study' by The Nature Conservancy and TRAFFIC (a joint wildlife trade monitoring program of WWF-World Wide Fund For Nature and IUCN-The World Conservation Union) (Robbins 1999).

Three varieties have been described within Baptisia tinctoria (Fernald 1937, 1950; Larisey 1940), var. tinctoria, var. crebra, and var. projecta. Following the Larisey interpretation, individuals found in Illinois belong to var. crebra (L.) R. Brown. However, most recent floras and other treatments of North American Fabaceae recognize B. tinctoria as a variable species but no longer consider the varieties worthy of taxonomic recognition (Gleason and Cronquist 1991, Kartesz 1994, Isely 1998, International Legume Database & Information Service 2002, United States Department of Agriculture, Natural Resources Conservation Service 2002).

Baptisia tinctoria has an unfortunate history of imprecise, albeit interesting, documentation and vouchering in Illinois. Its early presence was noted from only general locations in northern Illinois with very few reports based on first hand field accounts. Babcock (1872) reported it as rare within a 40 mile region of Chicago, Patterson (1876) reported it from northern counties based on notes from Mary E. Holmes, and Brendel (1887) noted its presence in northern Illinois. Higley and Raddin (1891) reported it as infrequent along the north and south shores of Lake Michigan. Gleason (1901) noted that it was present in dry prairies, but did not occur south of Macon County. The four known voucher specimens of B. tinctoria (housed at the University of Illinois Herbarium [ILL]), Urbana, Illinois) are equally indistinct, each accompanied by very incomplete location and date information. Specimens referred to in Snare and Hicks (1898) and Fernald (1940) could not be verified.

Within about a decade after the early 1900's, Baptisia tinctoria seemed to disappear from the Illinois landscape. Early authors Gates (1914) and Fuller (1917) made no mention of the species. Pepoon (1927), Fernald (1945), Gambill (1953), and Jones and Fuller (1955) referenced or summarized historic accounts while commenting on its absence in the flora. Based on specimens collected in Indiana, Larisey (1940) reported the presence of B. tinctoria and B. tinctoria var. crebra, and first described the hybrid B. Xdeamii Larisey (cross between B. tinctoria var. crebra and B. lactea [Raf.] Thieret) but listed no accounts from Illinois. Bowles et al. (1991) found no populations or individuals during an intensive survey in 1987. Swink and Wilhelm (1994) commented on the absence of B. tinctoria in their region, but noted the first recorded presence of B. Xdeamii in Illinois discovered in 1992 by Gerould Wilhelm near St. Anne in Kankakee County (voucher specimens at the Morton Arboretum [MOR], Lisle, Illinois). Most recently, it remained included in Mohlenbrock (2002) with the comment "very rare, and probably extirpated from Ill."

On July 26, 2002, while conducting a vegetation survey of one of the Pembroke Savannas in Kankakee County, Illinois, approximately 2 miles south of Leesville, the authors came upon a small population of B. tinctoria at the edge of an oak sand savanna bordering an abandoned old (successional) field. The population was completely surrounded by almost head-high Quercus velutina shoots in an area approximately six meters in diameter. It consisted of three large bushy plants and half a dozen smaller individuals. The larger plants contained many blooms and legumes, allowing them to be identified in the field. Baptisia lactea individuals occurred in this same vicinity, along with intermediate plants that shared characteristics of the two species. Specimens of each were collected. The specimens of B. tinctoria (Feist #1900) and B. lactea (Feist #1899) conformed to the descriptions in Fernald (1937, 1950) and Larisey (1940) and matched herbarium (ILL) specimens from Illinois, Indiana, and Michigan. The intermediate specimens were identified as B. Xdeamii based on descriptions in Larisey (1940). Wilhelm's specimen of B. Xdeamii had also been collected from this vicinity in 1992 (Swink and Wilhelm 1994, vPlants 2002). Species immediately associated with the B. tinctoria population included Quercus velutina, Q. alba, Rhus copallina, Rubus hispidus, Salix humilis, Scleria triglomerata, and Carex swanii. The woodlands edge was dominated by Quercus alba.