Polytaenia nuttallii DC.
CC = 8
CW = 5
MOC = 46
Family - Apiaceae
Habit - Perennial forb with somewhat tuberous-thickened taproot.
Stem - Ascending to erect, to 100 cm long, relatively stout, minutely hairy and/or roughened, especially around the nodes and toward the tip.
Leaves - Basal, alternate, and sometimes opposite, with several basal leaves usually present at flowering, mostly short- to long-petiolate, the uppermost leaves often sessile or nearly so, the sheathing bases slightly to moderately inflated. Leaf blades 2-18 cm long, oblong-ovate to broadly ovate-triangular in outline, pinnately or less commonly ternately then pinnately 2 times compound, the leaflets 10-50 mm long, oblong or ovate, deeply pinnately lobed, narrowed or rounded at the base, the segments or lobes narrowly oblong to oblanceolate, less commonly ovate, entire or with few coarse teeth or lobes, narrowed to a blunt or sharp point or rounded at the tip, the undersurface roughened with minute teeth along the veins.
Inflorescences - Terminal and axillary, compound umbels, short- to long-stalked, the stalks minutely hairy and/or roughened. Involucre absent. Rays 10-20, 1-4 cm long, minutely hairy and/or roughened. Involucel of 2-8 bractlets, these shorter than to longer than the flower stalks, linear, usually hairlike. Flowers mostly numerous in each umbellet, the stalks 3-5 mm long, minutely hairy and/or roughened.
Flowers - Sepals reduced to 5 small teeth, these usually persistent in fruit. Petals 5, oblong to narrowly obovate, shallowly notched or narrowed or tapered abruptly to a short, slender tip, this usually curved or curled inward, yellow. Stamens 5, the filaments free. Pistil 1 per flower, composed of 2 fused carpels, the ovary inferior with a swollen nectar disc at the tip, glabrous, the styles 2, often expanded at the base.
Fruits - Schizocarps 5-11 mm long, oblong-elliptic or oblong-obovate in outline, rounded at the base, strongly flattened dorsally, glabrous, yellowish brown to dark brown, the mericarps with the dorsal and intermediate ribs nervelike and obscure, the lateral ribs with thick, corky, lighter-colored wings.
Flowering - April - June.
Habitat - Glades, upland prairies, savannas, forest openings, roadsides, usually on calcareous substrate.
Origin - Native to the U.S.
Lookalikes - Broadly, Pastinaca sativa.
Other info. - This distinctive plant is found in Missouri mainly in counties to the south of the Missouri River. Its North American distribution is restricted to the U.S. Midwest. Its stocky, robust appearance, divided parsley-like leaves, and yellow umbels make it hard to mistake for anything else in the state. Although the umbels somewhat resemble those of the wild parsnip (Pastinaca sativa), the leaves have a different color, texture, and division pattern. Polytaenia nuttallii is a conservative species found only in high-quality habitats.
Photographs taken at Shaw Nature Reserve, Franklin County, MO, 06-15-2007, Drury-Mincy Conservation Area, Taney County, MO, 04-14-2012, and Danville Conservation Area, Montgomery County, MO, 04-28-2016, 05-08-2018, and 05-15-2018 (SRTurner).