Iva annua
Sp. Pl. 2: 988. 1753.
Synonyms: Iva annua var. caudata (Small) R. C. Jackson Iva annua var. macrocarpa (S. F. Blake) R. C. Jackson
Revision as of 19:37, 16 December 2019 by FNA>Volume Importer
Annuals, (10–)50–100(–150+) cm. Stems erect. Leaves: petioles 5–20(–30) mm; blades deltate or ovate to elliptic, trullate, or lanceolate, 30–100(–150)+ × 8–45(–80) mm, margins ± toothed, faces ± scabrellous, gland-dotted. Heads in ± spiciform arrays. Peduncles 0–1 mm. Involucres ± hemispheric, 3–4(–5) mm. Phyllaries: outer 3–5 distinct, ± herbaceous. Paleae linear, 2–2.5 mm. Pistillate florets 3–5; corollas 0.5–1 mm. Functionally staminate florets 8–12+; corollas 2–2.5 mm. Cypselae 2–3 mm. 2n = 34.
Phenology: Flowering Jul–Nov.
Habitat: Disturbed sites, moist soils
Elevation: 10–500 m
Distribution
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Ala., Ark., Colo., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Mass., Mich., Miss., Mo., Nebr., N.Mex., N.C., N.Dak., Ohio, Okla., Pa., S.C., S.Dak., Tenn., Tex., Va., W.Va., Wis., Mexico (Tamaulipas).
Discussion
Selected References
None.
Lower Taxa
None.