Croton argenteus |
Croton capitatus |
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silver July croton |
capitate croton, hogwort, woolly croton |
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Habit | Herbs, annual, 2–12 dm, monoecious. | Herbs, annual, 3–8 dm, monoecious. |
Stems | branching once into 2–3 branches, tomentose. |
well branched distally, stellate-hairy, hairs whitish to pale yellow, glabrescent. |
Leaves | sometimes clustered near inflorescences; stipules linear-subulate, 4–11 mm, unlobed or deeply divided; petiole 0.3–8 cm, glands absent at apex; blade ovate to ovate-oblong, 2–15 × 1.5–8 cm, base obtuse, cuneate, or subtruncate, margins denticulate, apex obtuse to rounded, abaxial surface pale green, not appearing brown-dotted, no stellate hairs with brown centers, densely stellate-hairy, adaxial surface green, less densely stellate-hairy. |
not clustered; stipules filiform, 2–5 mm; petiole 0.5–6 cm, glands absent at apex; blade ovate to lanceolate-elliptic, 3–8(–15) × 1–4 cm, base rounded to cuneate, margins entire, apex obtuse to acute or rounded, abaxial surface light green, not appearing brown-dotted, no stellate hairs with brown centers, adaxial surface darker green, both appressed stellate-hairy. |
Inflorescences | bisexual, congested racemes, 1–4 cm, staminate flowers 4–10, pistillate flowers 3–6. |
bisexual, racemes or capitate, 1.5–3 cm, staminate flowers 5–15, pistillate flowers 3–6. |
Pedicels | staminate 2–3 mm, pistillate 1–4 mm (3–5 mm in fruit). |
staminate 0.5–1.5 mm, pistillate 0–1.5 mm. |
Staminate flowers | sepals 5, 1.5–2 mm, abaxial surface stellate-hairy; petals 5, oblong, 2–3 mm, abaxial surface glabrous except margins ciliate; stamens 10–13. |
sepals 5, 0.8–1 mm, abaxial surface stellate-hairy; petals 5, linear-oblong-lanceolate, 0.8–1 mm, abaxial surface stellate-hairy; stamens 7–12. |
Pistillate flowers | sepals 5, unequal, 4–8 mm, margins deeply laciniate, apex incurved, abaxial surface stellate-hairy; petals 0; ovary 3-locular; styles 3, 2–3 mm, 4-fid, terminal segments 12. |
sepals 6–9, equal, 7–10 mm to 15 mm in fruit, opening broadly and persistent after capsule dehiscence, margins entire, apex recurved, abaxial surface stellate-hairy; petals 0; ovary 3-locular; styles 3, 2–3 mm, 2–3 times 2-fid, terminal segments 12–18(–24). |
Capsules | 5 × 7 mm, smooth; columella 3-angled. |
7–9 × 5–6 mm, smooth; columella tipped with 3-pronged grappling hooklike appendage. |
Seeds | 3.2–3.8 × 2.4–3 mm, dull. |
5 × 4.5–5 mm, shiny. |
2n | = 20. |
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Croton argenteus |
Croton capitatus |
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Phenology | Flowering Jun–Dec. | Flowering Jun–Oct. |
Habitat | Disturbed sites, waste areas, levees. | Pastures, old fields, cultivated land, prairies, floodplains, longleaf pinelands, sandy to loamy soils. |
Elevation | 0–50 m. (0–200 ft.) | 0–300 m. (0–1000 ft.) |
Distribution |
TX; e Mexico; Central America; South America; West Indies [Introduced in North America] |
AL; AR; DC; DE; IA; IL; IN; KS; KY; MA; MD; MO; MS; NC; NE; NJ; OH; OK; PA; SC; TN; TX; VA; WV
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Discussion | Croton argenteus, which in the flora area is known only from Cameron and Hidalgo counties, may be a fairly recent introduction into the United States; the earliest known collections date from 1923. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Croton capitatus is frequently confused with C. heptalon and C. lindheimeri. Croton capitatus usually has some leaves that are blunt-tipped and mucronate (versus all or most acute in C. lindheimeri), and the pistillate sepals are longer than the ovary, with tips that flare outward at anthesis. Also, C. capitatus has petioles roughly equal in length from the middle to the tip of the stem, whereas C. lindheimeri has petioles that decrease more markedly in length from the middle to the tip of the stem. Occurrences of C. capitatus east of the Appalachian Mountains are likely adventive. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 211. | FNA vol. 12, p. 212. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | family euphorbiaceae Julocroton argenteus | Heptallon graveolens, Oxydectes capitata, Pilinophytum capitatum |
Name authority | Linnaeus: Sp. Pl. 2: 1004. (1753) — (as argenteum) | Michaux: Fl. Bor.-Amer. 2: 214. (1803) — (as capitatum) |
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