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Artemisia
See list of 13 species in this genusReference: Shultz (2006).
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1a. Plants definitely woody; capitula homogamous—all the flowers bisexual and with 5-lobed corollas; leaves persistent, the principal ones with blades narrow-obtriangular with three apical teeth
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1b. Plants herbaceous, suffrutescent, or ± woody; capitula heterogamous—the marginal flowers carpellate with 2-lobed corollas, the inner flowers bisexual or functionally staminate with 5-lobed corollas; leaves usually deciduous, the principal ones with pinnatifid blades ( A. dracunculus often and A. ludoviciana usually with simple leaves)
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2a. Central flowers of disk functionally staminate, the gynoecium of these flowers with an abortive ovary and undivided style that is included within the short-tubular to subglobose corolla
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3a. Leaf blades 2- or 3-times pinnatifid into narrow segments [Fig. 379]; herbage scarcely odorous, if at all
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3b. Leaf blades entire or sometimes the lower with 2–5 lobes; herbage faintly to strongly tarragon-scented
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2b. Central flowers of disk bisexual, the gynoecium of these flowers with a fertile ovary and divided style that is often exserted beyond the tubular to funnelform corolla
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4a. Receptacle densely and conspicuously hairy between the disk flowers
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5a. Reproductive stems 4–6 (–10) dm tall; leaf blades 3–8 cm long, the ultimate segments oblong to oblanceolate, 1.5–4 mm wide
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5b. Reproductive stems 1–4 dm tall; leaf blades 0.5–1.5 (–2.5) cm long, the ultimate segments linear, up to 1 mm wide
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4b. Receptacle without hairs
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6a. Plants annual or biennial, arising from a taproot; leaf blades glabrous on both surfaces; involucral bracts glabrous
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7a. Capitulescence dense, resembling a spike, 2–4 cm wide, with inconspicuous peduncles and erect or ascending capitula; involucre 2–3 mm tall; plants inodorous or nearly so; leaf blades 1- or 2-times pinnatifid
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7b. Capitulescence open, resembling a panicle, 10–20 cm wide, with conspicuous peduncles and nodding capitula [Fig. 378]; involucre 1–2 mm tall; plants sweet-scented; leaf blades 2- or 3-times pinnatifid
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6b. Plants perennial, arising from a rhizome or woody caudex; leaf blades tomentose on one or both surfaces, sometimes sparsely so; involucral bracts tomentose, at least sparsely so
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8a. Plants suffrutescent or ± woody, without rhizomes; leaves 2- or 3-times pinnatifid into linear or filiform segments 0.5–1.5 mm wide; involucre 2–3.5 (–4) mm tall
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9a. Leaf blades 3–6 cm long, thinly tomentose on the abaxial surface, glabrous on the adaxial surface; plants ± shrubby, 5–20 dm tall
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9b. Leaf blades 1–3 cm long, tomentose on both surfaces; plants suffrutescent, 4–10 dm tall
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8b. Plants herbaceous, dying back to the ground each year, with rhizomes; leaves entire or 1- or 2-times pinnatifid into lobes wider than 1.5 mm (the ultimate lobes often narrower than 1.5 mm in A. carruthii); involucre 2.5–7.5 mm tall
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10a. Leaf blades entire or toothed, the lower sometimes inconspicuously lobed, but the primary lobes without additional teeth or lobes
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10b. Principal leaf blades 1- or 2-times pinnatifid, the primary lobes either entire or with additional teeth or lobes
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11a. Leaf blades concolorous, densely white-tomentose on both faces; involucre 6–7.5 mm tall; disk corollas 3.2–4 mm long
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11b. Leaf blades bicolorous, white-tomentose on the abaxial surface, green and glabrous or sparsely pubescent on the adaxial surface; involucre 2.5–4.5 mm tall; disk corollas 1–2.8 mm long
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12a. Reproductive stems (4–) 6–19 dm tall; leaf blades with ultimate segments wider than 2 mm; capitula with 7–10 marginal carpellate flowers
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12b. Reproductive stems 1.5–4 (–7) dm tall; leaf blades with ultimate segments narrower than 2 mm; capitula with 1–5 marginal carpellate flowers
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Each photo represents one species in this genus.