Lechea stricta Leggett ex Britton
Family: Cistaceae
Prairie Pinweed
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Perennial herb 10 - 45 cm tall

Stem: one to few, often trailing within first 5 cm of base, then abruptly erect, unbranched below inflorescence, grayish with covering of long appressed hairs. Late in the season producing short (2 - 3 cm) basal shoots with numerous, crowded leaves.

Leaves: alternate, ascending to appressed, stalkless, grayish green, non-toothed, one-nerved, small (1.3 - 2 cm long), longer than wide, narrowly lance-shaped or wider past middle, but with pointed tips, all of lower surface densely covered with white or gray, soft, appressed, matted hairs. The leaves on the later produced basal shoots differ from the upright stem leaves by being more crowded, and only 3 - 5 mm long.

Inflorescence: starting about midway or in upper third of stem, very narrow, leafy, densely gray-hairy, with ascending lateral branches which are held at a maximum angle of 30 degrees from main stem. The final branchlets of the inflorescence end in short, crowded, spike-like clusters of stalked, tiny (under 3 mm tall), reddish, non-showy, radially symmetric flowers. All branches, branchlets, and flower stalks very hairy.

Sepals: five, but in two series, with outer two linear and only up to two-thirds as long as the 1.6 - 1.8 mm tall, 1.2 - 1.3 mm wide, three-nerved, broadly egg-shaped, round-tipped inner three. All five sepals are longer than the petals, and densely covered with appressed whitish hairs.

Petals: three, mostly concealed by sepals, reddish, small, and rarely expanding.

Stamens: typically five to twenty, with short anthers on relatively long, slender filaments.

Pistil: with one, single-chambered, superior ovary; no style; but three, feather-like stigmas.

Fruit: single-chambered, three-valved, over 1.2 mm wide, almost spherical capsules which are partly enclosed by the persistent sepals, and sit on at least 2 mm long stalks. The capsules are about the same height as the sepals, so the very tip of the capsule is barely exposed above the sepal tips.

Seeds: three or four per capsule, smooth, narrowly egg-shaped, and released when top of capsule opens down the three lengthwise valves.

Similar species: Lechea stricta is probably most similar to L. maritima from the Atlantic coast, but that species has more widely spreading inflorescence branches (angle to the main stem at least forty-five degrees), and the leaves on the basal shoots are more elliptic and usually over 0.5 cm long. In the Chicago Region, this species may be confused with L. pulchella var. moniliformis or L. intermedia, except both those species tend to be more green than gray in aspect, the leaves are normally only hairy underneath along the midrib and edges, plus their inflorescence branches tend to be more spreading (more than a thirty degree angle from the main stem). L. intermedia further differs by having seeds covered with a veiny or wrinkled, whitish gray membrane.

Flowering: July to September

Habitat and ecology: Not common, in dry sandy prairies near the western shores of Lake Michigan, and also localized on a gravely kame (short hill or mound of glacial drift material) in McHenry county, Illinois.

Occurence in the Chicago region: native

Notes: This species may no longer exist in Indiana. Only three specimens from the late 1800's have been verified as L. stricta (see specimens here as well as information in Swink and Wilhelm 1994), so it is likely it was never common in Indiana . This makes sense as the Chicago Region is at the eastern edge of the range for this more western species.

Etymology: Lechea is named after John Leche (1704 - 1764), a Swedish botanist. Stricta is a Latin word meaning tight, close, straight, erect, or upright; in reference to the tight upright branches of this species.

Author: The Field Museum

From Flora of Indiana (1940) by Charles C. Deam

Reported by Peattie from Lake County. A. R. Hodgdon, who monographed the genus, found specimens in the Field Museum from Lake and Starke Counties collected by E. J. Hill.

Plants canescent; stems commonly procumbent for 1-5 cm, thence abruptly erect, 1-4 dm; lvs canescent across the surface beneath, those of the basal shoots crowded but not conspicuously whorled, 3-5 mm, narrowly lanceolate, the cauline ones narrowly lanceolate to oblanceolate, to 15 mm; panicle forming a third to half the plant, with closely ascending branches, the ultimate branchlets crowded and racemiform; pedicels equaling or surpassing the cal, very hairy; sep densely hairy, the inner 3 about equaling the subglobose fr; seeds 3 or 4. Dry, sandy woods, prairies, and shores; s. Ont.; nw. Ind. to Minn. and Nebr.

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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