2007 THE MICHIGAN BOTANIST 127

NOTEWORTHY COLLECTION

WISCONSIN

Ranunculus cymbalaria Pursh (). Alkali buttercup, seaside crow- foot. Previous knowledge. Seaside crowfoot is distributed heterogeneously through- out much of North America, but it is conspicuously absent in southeastern U.S. (USDA 2007). The halophile-like species flourishes on mud and gravel, particu- larly under brackish or alkaline conditions and limited competition. The floristic rating as a wetlands indicator for R. cymbalaria is OBL (Obligate Wetland). In Wisconsin, R. cymbalaria is one of the more diminutive and rare butter- cups. The creeping perennial forb is a state threatened species, known from just seven counties out of 72. With one inland exception, Walworth County, R. cym- balaria has been collected from six counties bordering the Great Lakes (Lake Michigan: Marinette, Brown, Sheboygan, Racine and Kenosha; Lake Superior: Douglas (Wisflora 2007). Historically, the species occurred in Walworth, Racine, Kenosha, Sheboygan and Manitowoc counties (Brynildson 1982) and was characterized as “Very rare along Lake Michigan shore in Manitowoc, Racine and Kenosha counties, inland only at Lake Geneva in Walworth County where collected in 1885” (Fassett 1947). While R. cymbalaria grows locally in disturbed habitats today, it has been suggested that human-caused alterations of lakeshore habitats was responsible for elimination of any known original/relict populations in Wisconsin (Brynild- son 1982). Since the early 1980s, the number of documented Wisconsin records for R. cymbalaria has quadrupled. The is locally abundant in bare muddy places, on wet clays, gravels, or gravel-sand or gravel-cinder mixtures, growing in ditches and railroad rights-of-way, as well as in street-side bluegrass lawns and mowed grassy highway strips, notably in the City of Superior (Douglas County) (Pers. Comm., Theodore S. Cochrane, 4 October 2007). The habitats often as- cribed to it—wet meadows, boggy shores, stream banks, and seepage areas— apply to only a fraction of the WIS collections (and several of these lack habitat information altogether) (Pers. Comm., Theodore S. Cochrane, 31 October 2007). Thus, R. cymbalaria is probably a native pioneer species, colonizing open dis- turbed wet substrates where competition for space and resources is sparse. This would explain its occurrence in artificial as well as more natural habitats, such as fluctuating Great Lakes shorelines. On a 0–10 scale, the coefficient of conser- vatism (C) for R. cymbalaria equals two (Wisflora 2007), further reinforcing the assessment that R. cymbalaria is likely a pioneer species. Significance of the report. On 28 June 2007, Thomas Underwood, Oshkosh, WI, discovered a small flowering population of R. cymbalaria on a (periodically wet) packed crushed dolomite gravel parking area at the end of Puchyan Marsh Road, Green Lake County, WI (SW 1/4 NW 1/4 Section 1, R12E, T16N; 128 THE MICHIGAN BOTANIST Vol. 46

N43°53.452 W089°01.626). Identification was verified and a voucher specimen collected as a county record by T. L. Eddy on 29 June 2007 (Eddy 5213, OSH). It is unknown if the Green Lake County population is part of the original (pre- European) local flora (Eddy 1996), but it is presumed that the plant was intro- duced via human-caused disturbances, e.g. road fill, vehicle and pedestrian traf- fic, or perhaps even by migrating waterfowl. A search of the roadbed and right-of-way vegetation did not reveal any other colonies of R. cymbalaria growing nearby. Associates of R. cymbalaria growing at the Green Lake County site include Agrostis gigantea, Ambrosia artemisiifo- lia, Centaurium pulchellum, Eleocharis acicularis, Hordeum jubatum and Jun- cus nodosus. Diagnostic characters. In Wisconsin R. cymbalaria flowers from June through July (Wisflora 2007), while Gleason and Cronquist (1991) report flow- ering from May to October. Stems are dimorphic: flowering stems (5–15 cm) and prostrate stolons that readily propagate clones via rooting nodes. The (1–10) yellow flowers are subtended by mainly basal leaf blades with cordate base and crenate margins above. The yellow petals are slightly longer (2–7 × 1–3 mm) than the five glabrous, spreading sepals (2.5–6 × 1.5–3 mm) (Whittemore 1997). The glabrous fruits are arranged on a cylindrical head up to 12 mm. Achenes are 1–1.4(2.2) × 0.8–1.2 mm long, longitudinally nerved with a persistent straight conic beak (0.1–0.2 mm). The most similar taxon to R. cymbalaria in Wisconsin is R. flammula, although the leaf shape immediately distinguishes them (Gleason and Cronquist 1991). Specimen citations. One voucher (GREEN LAKE CO.: Eddy 5213, OSH; ac- cession number OSH-115423) was collected and examined for this report. A list of other Wisconsin herbarium records with specimen citations is available online via Wisflora (http://www.botany.wisc.edu/wisflora/).

LITERATURE CITED Brynildson, I. (1982). Wisconsin’s Endangered Flora. Madison: Wisconsin Department of Natural Resources, Office of Endangered & Nongame Species. Eddy, Thomas L. (1996). A Vascular Flora of Green Lake County, Wisconsin. Transactions of the Wisconsin Academy of Science, Arts and Letters. 84:23–67. Fassett, Norman C. (1947). Preliminary reports on the flora of Wisconsin. No. 38. Ranunculaceae. Trans. Wis. Acad. Sci. 38:189–209. Gleason, H. A. & A. Cronquist. (1991). Manual of Vascular of Northeastern United States and Adjacent Canada. New York Botanical Garden, Bronx, NY. United States Department of Agriculture. (2007). Plants profile. Retrieved 30 October 2007, from Plants Database Web site: http://plants.usda.gov/ Wisflora: Wisconsin species. (2007). Retrieved 11 July 2007, from Wisflora: Wiscon- sin Vascular Plant Species Web site: http://www.botany.wisc.edu/wisflora/ Whittemore, A. T. (1997). 2. L. Pp. 88–135 in Flora of North America Editorial Com- mittee, eds. Flora of North America Volume 3, Magnoliophyta: Magnoliidae and Hammamelidae. Oxford University Press, New York.

Thomas L. Eddy, 426 Walker Avenue, Green Lake, WI 54941 Email: [email protected]