Leavenworth's Eryngo

Eryngium leavenworthii T. & G. Fl. N. Am. 1: 604. 1840
Rather slender, glabrous and purplish perennials (?), 5-10 dm. high, from a slender taproot, the stems erect, divaricately branching, leafy; lower cauline leaves broadly oblanceolate, 3-6 cm. long, 1-2 cm. broad, short-petiolate, the upper broadly ovate to orbicular, sessile, deeply palmately parted, the divisions pinnatifid with pungent lobes, the venation reticulate; inflorescence sparingly cymose, the heads large, few or more, short-pedunculate, the flowers numerous; heads purplish, ovoid to ovoid-cylindric, 2-3.5 cm. long, 15-25 mm. broad; bracts about 8, oblong, 2-4 cm. long, spinose-pinnatifid like the upper leaves, about equaling the heads; bractlets linear, 1 cm. long, spinose-lobed with 3-7 prominent teeth, exceeding the fruit; coma of about 8 prominent spinescent bract-like bractlets, 1-2 cm. long; sepals oblong, 5 mm. long, spinose-pinnatifid toward the apex; petals oblong, 2-3 mm. long; styles shorter than the sepals; fruit oblong, 2-4 mm. long, densely covered on the angles and faces with linear or claviform white scales 1-2 mm. long.
Type locality: Red River, "Arkansas," Leavenworth.
Distribution: Kansas to Texas (Lindheimer 836, 837, Palmer 9008).

Eryngium leavenworthii, also known as Leavenworth's eryngo, is an annual plant in the family Apiaceae that is native to the central United States. It can reach heights up to 3 feet. It inhabits dry rocky prairies, roadside fields, open woodlands and waste areas. The plant is mostly found in areas with limestone or chalk soils. Its flowers appear between July and September, although in some areas the flowers may bloom as late as November. The flower ranges in length from 1 1/2" to 3" and in width approximately 1/2". It is frequently mistaken for thistle. The flowers sit atop elongated stems on spiked leaves and form cones of purple or wine colored, tightly clustered blossoms that resemble small fuzzy pineapples. It was named after, Melines Conklin Leavenworth (1796–1862) who is credited with its discovery.