Jacquemontia tamnifolia Griseb.
Source: Collecitons database
Family: Convolvulaceae
Jacquemontia tamnifolia image
Steve Hurst  
Annual herb Stem: erect or slightly twining, bristly hairy. Leaves: alternate, long-stalked, heart-shaped to egg-shaped, non-toothed, hairy. Flowers: numerous, blue, small (around 1 cm tall), tubular to funnel-shaped, and stalkless in tight axillary or terminal head-like clusters atop long and bristly stalks (longer than leaf stalk). Sepals: five, linear to awl-shaped, bristly hairy, sometimes of unequal lengths. Petals: five, but fused into a tube or funnel. Stamens: five, attached to inside of petal tube. Pistil: with one, usually two-chambered, superior ovary; and one style with two thickened and rounded stigmas. Fruit: two-chambered, two to four-valved, rounded capsules with two to six seeds.

Similar species: Jacquemontia tamnifolia may appear superficially similar to members of the genera Calystegia, Convolvulus, or Ipomoea, but with its numerous small flowers in dense, head-like clusters and densely bristly sepals it is easy to separate it from those more common, non-clustered, and typically larger-flowered genera.

Flowering: August to October

Habitat and ecology: A rare introduction from tropical America, only found once in waste ground around a grain elevator.

Occurence in the Chicago region: non-native

Notes: This plant can be very weedy in more southern climates. It rarely persists this far north.

Author: The Field Museum

A widespread weed in tropical Amer. and s. U.S., has been collected as far n. as n. Ill. and se. Va. It will key to Calystegia, from which it obviously differs in its densely cymose-capitate clusters of blue fls ca 1 cm.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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