Plagiobothrys hispidulus (Greene) I.M. Johnston (redirected from: Plagiobothrys nelsonii)
Family: Boraginaceae
[Allocarya cognata Greene,  more...]
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Annual herb 10 - 60 cm tall

Leaves: opposite in lowest four pairs (bracts alternate at base of inflorescence), more or less stalkless, bristly-hairy, 3 - 9 cm long, 0.2 - 0.5 cm wide, linear with pointed tips.

Inflorescence: single or paired, terminal, up to 20 cm long, loose, elongated spike-like branches with tightly coiled tips (straighten as elongates), and well-spaced, short-stalked flowers mostly without subtending bracts except possibly a few at very base.

Flowers: short-stalked, white with yellow centers, small (0.5 - 2 mm broad), radially symmetric, somewhat funnel-shaped with well-developed tube, and shorter, spreading, somewhat egg-shaped lobes with narrowed, somewhat pointed or blunt tips.

Sepals: five, stiff-hairy, linear, longer than petal tube, 2 - 4 mm long when in fruit.

Petals: five, but fused for over three-fourths their length into a relatively narrow tube, then separating into five, spreading, somewhat egg-shaped lobes with somewhat blunt-pointed tips. At the base of the petal lobes, there are five, yellow, small projections or appendages (fornices).

Stamens: five, attached to inside of petal tube by very short filaments, and the 0.3 - 3 mm long, oblong anthers not extending past the petal tube.

Pistil: with one, deeply four-lobed, superior ovary; one, very short (shorter than nutlets), inconspicuous style; and one, unlobed stigma which does not extend past the petal tube.

Fruit: a cluster of four, erect, wrinkled, bumpy to pitted, 1 - 1.5 mm tall, somewhat three-angled, elongate egg-shaped nutlets with narrowed tips, and a prominent lengthwise ridge (keel) running down the inner side. The nutlet clusters are enclosed by the erect, but narrow sepals.

Stems: several or many, prostrate or ascending, branching above, slender, appressed hairy.

Similar species: Plagiobothrys scouleri var. hispidulus is similar to several species of Myosotis, but forget-me-nots always have alternate leaves with blunt to rounded tips, the flowers are normally blue (with yellow center), the sepals are fused at least at their base, the petal lobes are obviously rounded and not narrowed at the tips, and the nutlets are smooth, shiny, and compressed laterally with an edgewise ridge.

Flowering: June to August

Habitat and ecology: Native to the Pacific Northwest of North America, this species is a very rare introduction and has only been found a few times in DuPage County, IL.

Occurence in the Chicago region: non-native

Etymology: Plagiobothrys comes from the Greek words plagios, meaning oblique or sideways, and bothros, meaning pit or scar, probably referring to the wrinkles and pitted marks on the nutlets. Scouleri is named after John Scouler (1804 - 1871), a Scottish botanist. Hispidulus means bristly or finely bristled.

Author: The Field Museum