Cuscuta fasciculata Yuncker

Stems yellow-orange, slender. Inflorescences dense to loose, umbelliform; bracts at base of clusters 1, at base of pedicels 0 or 1, triangular-ovate, membra­nous, margins entire, apex acute. Pedicels 2–10 mm. Flow­ers 5-merous, 2–3 mm, mem­branous, not papillate or sometimes papillate on adaxial face of corolla lobes; calyx straw yellow, campan­ulate, equaling corolla tube length, divided 2/3 its length, finely reticulate, slightly shiny, lobes triangular-ovate, bases not overlapping, margins entire, midvein not carinate, without multicellular protuberances, apex obtuse to acute; corolla white, drying creamy white or brown, 2–2.5 mm, tube campanulate, 0.6–1.2 mm, not saccate, lobes reflexed, oblong to lanceolate, longer than corolla tube length, margins entire, apex obtuse to acute, straight; infrastaminal scales subspatulate to obovate, 0.8–1.2 mm, equaling or longer than corolla tube length, bridged at 0.1 mm, rounded, uniformly densely fimbriate, fimbriae 0.1–0.3 mm; stamens exserted, shorter than corolla lobes; filaments 0.4–0.7 mm; anthers 0.4–0.6 × 0.2–0.3 mm; styles filiform, 0.8–1.7 mm, longer than ovary. Capsules depressed-globose, 1–2.5 × 0.7–1.2 mm, thickened and slightly raised around inconspicuous interstylar aperture, translucent, surrounded or capped by withered corolla, dehiscence circumscissile. Seeds 2–4, angled, ovate to broadly ellipsoid or subglobose, 0.8–1.2 × 0.6–0.8 mm, hilum region terminal.

Flowering Apr–Dec. Hosts: Acleisanthes, Allionia, Alternanthera, Amaranthus, Atriplex, Boerhavia, Gilia, Iresine, Kallstroemia, Salsola, Sesuvium, Suaeda, Tidestromia, Trianthema, Tribulus; 10–2500 m; Ariz., Colo., Fla., Kans., La., N.Mex., Okla., Tex.; Mexico; West Indies; South America.

Cuscuta umbellata is currently included in North American noxious weed lists although there is no evi­dence that it attacks crops.