Chaerophyllum procumbens (L.) Crantz
CC = 2
CW = -3
MOC = 79
Family - Apiaceae
Habit - Taprooted annual forb.
Stems - Spreading to loosely ascending, to 60 cm, multiple from the base, branching, angled, glabrous to sparse retrorse pubescence toward the base, slightly fragrant with a scent like parsley.
Leaves - Alternate, to 12 cm long, typically sessile or with a short flattened sheathing petiole, bipinnately divided. Rachis and petiolules with adaxial groove, nearly glabrous. Leaflets deeply lobed to pinnatifid. Ultimate divisions 1-8 mm long, 1-4 mm wide, oblong-elliptic, entire, rounded to subacute at apex. Leaves green above and light green below.
Inflorescence - Terminal and axillary, compound or sometimes simple (1-rayed) umbels, sessile to short- or long-stalked. Rays 0.3-1.5 cm long at flowering, elongating to 5.5 cm at fruiting, sparsely to moderately short-hairy. Rays typically 3 per inflorescence. Umbellets subtended by 4-6 ovate to rotund bractlets, these mostly longer than the flowering pedicels. Pedicels 2-3 mm long in flower, 5-6 mm long in fruit, glabrous, slender, uniformly linear, not flared at the tip.
Flowers - 2-6 per umbellet. Petals 5, white, glabrous, 1 mm long, 0.6 mm broad, elliptic, acute, spreading, with single visible midvein. Stamens 5, spreading, alternating with the petals. Filaments glabrous, white, 0.6 mm long. Anthers brownish-yellow, 0.1 mm long. Styles very short, expanded at base into thick stylopodia. Ovary glabrous, green, inferior, 1.0-1.1 mm long in flower, 2-carpellate. Sepals minute to absent.
Fruits - Schizocarps 5-10 mm long, glabrous, elliptic-oblong, with one seed per carpel.
Flowering - March - May.
Habitat - Rich mesic forest, alluvial soils, bluffs, glades, pastures, roadsides, railroads.
Origin - Native to U.S.
Lookalikes - Chaerophyllum tainturieri. Vegetatively the plant resembles several other unrelated species (Daucus carota, Cystopteris spp., and others) and can be difficult to distinguish reliably.
Other info. - This familiar member of the springtime flora is common across Missouri. Its main U.S. distribution is in the eastern half of the country, where it is most common toward the central latitudes of that area. In flower it is easily identified to genus, though differentiation from C. tainturieri can be difficult at this stage. The hairiness of the stems does not seem to be a reliable character. The identity can be determined with more confidence when the plants are in fruit, when the fruit stalks will be slender and uniformly linear. C. tainturieri, in contrast, has fruit stalks which are flared toward the tips. Vegetatively the plant can resemble several other species.
Photographs taken at the Dr. Frederick Marshall Conservation Area, Platte County, MO., 5-6-01.