Annual herb 30 cm - 0.7 m tall Stem: upright, densely covered with simple and star-shaped grayish hairs (mainly on lower part). Flowers: in loosely branched clusters, pale yellow, 4 - 5 mm long, 1.2 mm wide at apex. Petals four. Stamens six. Fruit: a pod, on 4 - 9 mm long stalks, upright, 2.5 - 5 mm long, to 4 mm wide, nearly round but slightly flattened, keeled, with a beak up to 2 mm long. Seeds reddish brown, about 1 mm long, oblong, triangular in cross-section, smooth, slightly glossy. Lower leaves: alternate, 5 - 6 cm long, 1.5 - 2 cm wide, oblong, densely covered with simple and star-shaped grayish hairs. Upper leaves: alternate, stalkless, clasping, smaller than lower leaves (progressively reducing in size), lance-shaped, base lobed (typically pointed), sometimes with a few small teeth along the margins near the tip, hairy.
Similar species: The similar Camelina sativa bears larger fruit.
Flowering: mid-May to mid-July
Habitat and ecology: Introduced from Europe. An infrequent weed of cultivated fields, waste ground, and roadsides. It is also found in nursery plots, sandy fields, and along railroads.
Occurence in the Chicago region: non-native
Notes: This plant is best viewed when the sky is overcast, because the flowers close and shrivel on sunny, warm days.
Etymology: Camelina comes from the Greek words camai, meaning dwarf, and linon, meaning flax (the term "dwarf" being used to mean "false"). Microcarpa means small-fruited.
Author: The Morton Arboretum
From Flora of Indiana (1940) by Charles C. Deam
This species is essentially a sandy ballast plant and is more or less frequent throughout the state. I have found it also along sandy roadsides and in sandy, fallow fields where I once found it as an abundant weed.
Indiana Coefficient of Conservatism: C = null, non-native
Erect, 3-7 dm, rough-hairy; lvs entire or remotely denticulate; frs erect, 2.5-5 mm, obscurely rugulose, on pedicels 4-9 mm; seeds ca 1 mm; 2n=40. Fields and waste places, usually in sandy soil; native of the Old World, established as a casual weed throughout most of the U.S. and s. Can. Apr.-June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.