Field dodder, cuscute des champs

Cuscuta pentagona Engelmann var. calycina Engelmann, Amer. J. Sci. Arts 45: 76. 1843

Stems yellow to orange, medium. Inflorescences dense, cor­ymbiform or glomerulate; bracts at base of clusters 1, at base of pedicels 0 or 1, ovate or ovate-triangular to lance­olate, membranous, margins entire, apex acute. Pedicels 0.3–2.5(–3.5) mm. Flowers (4 or)5-merous, 1.9–3.6 mm, membranous, not papillate; calyx yellow, cupulate, equaling corolla tube length, divided 2/5–3/5 its length, reticulate, shiny, lobes ovate-triangular, bases over­lapping, margins entire, midvein not carinate, without multicellular protuberances, apex obtuse to rounded; corolla creamy white, drying creamy or golden yellow, 2–3.5 mm, tube campanulate, (1.1–)1.5–1.9 mm, not saccate, lobes spreading, triangular to triangular-lanceolate, equaling corolla tube length, margins entire, apex acute to acuminate, inflexed; infrastaminal scales oblong-ovate to spatulate, rounded, 1.5–2 mm, equaling or exceeding corolla tube length, bridged at 0.3–0.5 mm, uniformly densely fimbriate, fimbriae 0.3–0.4(–0.5) mm; stamens exserted, shorter than corolla lobes; filaments 0.4–0.7 mm; anthers (0.3–)0.4–0.5 × 0.2–0.3 mm; styles filiform, 0.5–1.6 mm, shorter than to equaling ovary. Capsules depressed-globose to depressed, 1.3–2.8 × 1.9–3.8 mm, not thickened or raised around relatively large interstylar aperture, sometimes translucent, to 1/3 enveloped by withered corolla, indehiscent. Seeds 4, angled, subglobose to broadly ellipsoid, 1.1–1.5 × 0.9–1.1 mm, hilum region subterminal. 2n = 56.

Flowering May–Nov. Hosts: Acanthaceae, Astera­ceae, Brassicaceae, Chenopodiaceae, Convolvulaceae, Euphor­biaceae, Fabaceae, Hydrophyllaceae, Polygona­ceae, Solanaceae, Urticaceae, Verbenaceae, and others (M. Costea and F. J. Tardif 2006); 0–2000 m; Alta., B.C., Man., N.S., Ont., Que., Sask.; Ariz., Ark., Calif., Colo., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., S.Dak., Tenn., Tex., Utah, Va., Wash., W.Va., Wis., Wyo.; Mexico; introduced widely.

Reports of Cuscuta campestris from New Brunswick, Newfoundland, and Prince Edward Island have not been verified.

Cuscuta campestris is the most widespread species of the genus in North America and perhaps the most successful and prevalent Cuscuta weed species world­wide; it has been recorded from South America, Europe, Asia, Africa, and Australia. It has been often referred to in North America as C. pentagona, which has smaller flowers and angled calyces. The two species are closely related; C. campestris is a hybrid species and C. pentagona is one of its progenitors (M. Costea et al. 2015b).