1. Geranium carolinianum L. (Carolina crane’s bill)

G. carolinianum var. confertiflorum Fernald

Pl. 422 p–r; Map 1883

Plants annual, usually taprooted. Aerial stems 10–65 cm long, erect to loosely ascending, moderately pubescent with short to long (0.2–1.0 mm), spreading to somewhat downward-pointing, mostly nonglandular hairs (usually with at least some glandular hairs toward the tip). Leaves basal and opposite, the basal ones long-petiolate, those of the stems with progressively shorter petioles. Leaf blades 1–7 cm long, wider than long to about as long as wide, kidney-shaped to nearly circular in outline, deeply 5–9-lobed, the lobes more or less obovate, mostly deeply and sharply 3- or 5-lobed, sometimes with additional lobes and/or teeth along the margin, the surfaces sparsely to densely pubescent with more or less appressed nonglandular hairs. Inflorescences appearing axillary and often also terminal, short- to long-stalked, consisting of pairs of flowers, these sometimes condensed into small clusters. Individual flower stalks 3–11 mm long, 0.5–1.1 times as long as the sepals, pubescent with spreading, mostly gland-tipped hairs. Sepals 5–6.5 mm long, becoming enlarged to 11 mm at fruiting, ovate, tapered or narrowed to a conspicuous, short, awnlike extension 1.5–2.0 mm long at the tip, pubescent with short to long, loosely ascending, glandular and nonglandular hairs. Petals 5.5–7.0 mm long, obtriangular, truncate to shallowly notched at the tip, pale pink or pale lavender to nearly white. Stamens 10. Staminodes absent. Mericarps 19–25 mm long at maturity, the seed-containing basal portion 3.0–4.5 mm long, the lateral surfaces smooth, pubescent with relatively long (0.7–1.5 mm) upward-pointing hairs (these mostly or all nonglandular), lacking a dorsal ridge or wing, the stylar beak with spreading to loosely ascending, all or mostly nonglandular hairs, the slender extension between the columnar portion and the stigmas 1–2 mm long. Seeds 2.0–2.2 mm long, the surface appearing smooth or with a faint fine network of ridges and pits. 2n=52. May–July.

Scattered nearly throughout the state (U.S., Canada, Mexico; introduced in South America, Caribbean Islands, and Asia). Glades, upland prairies, sand prairies, tops and ledges of bluffs, openings of mesic upland forests, and banks of streams and rivers; also pastures, fallow fields, roadsides, railroads, ditches, levees, and open disturbed areas.

Some earlier authors (Steyermark, 1963) recognized two or more varieties within G. carolinianum, based on subtle differences in pubescence and other floral characteristics. Aedo (2000) documented that pubescence, sepal nervation, and seed shape, among other characters varied on the same individual in some populations, thus precluding the formal recognition of such varieties. Geranium carolinianum is the only Missouri species of the genus with consistently pale-colored flowers.