Annuals, 20-150 cm. Stems erect. Leaves opposite and alternate; petiole 2.5-3.5(-6) cm; blade deltate to lanceolate or elliptic, 2.5-5.5(-9) × 2-3(-5) cm, pinnately 1- or 2-lobed, abaxially sparsely pilosulose to strigillose, adaxially strigillose, both surfaces gland-dotted, base cuneate, ultimate margin entire or toothed. Female capitula clustered, proximal to male; floret 1. Male capitula: peduncles 0.5-1.5 mm; involucres shallowly cup-shaped (usually without black veins), 2-3 mm in diam., glabrous or hispid to pilosulose; florets 12-20. Burs ± globose to pyriform, 2-3 mm, ± pilosulose, spines or tubercles 3-5, near middle or apex, conical to acerose, 0.1-0.5 mm, tips straight. Fl. Jul-Oct, fr. Sep-Oct. 2n = 34, 36.
Annuals, 10–60(–150+) cm. Stems erect. Leaves opposite (proximal) and alternate; petioles 25–35(–60+) mm; blades deltate to lanceolate or elliptic, 25–55(–90+) × 20–30(–50+) mm, 1–2-pinnately lobed, bases cuneate, ultimate margins entire or toothed, abaxial faces sparsely pilosulous to strigillose, adaxial faces strigillose, both gland-dotted. Pistillate heads clustered, proximal to staminates; florets 1. Staminate heads: peduncles 0.5–1.5 mm; involucres shallowly cup-shaped (usually without black nerves), 2–3+ mm diam., glabrous or hispid to pilosulous; florets 12–20+. Burs: bodies ± globose to pyriform, 2–3 mm, ± pilosulous, spines or tubercles 3–5+, near middles or distal, ± conic to acerose, 0.1–0.5+ mm, tips straight. 2n = 34, 36.
"Annual weed 3–10 dm, branching at least above, variously hairy or in part subglabrous; lvs opposite below, alternate above, once or more often twice pinnatifid, the blade narrowly to broadly ovate or elliptic in outline, 4–10 cm, the middle and lower ones, at least, evidently petiolate; staminate invols short-pedunculate, symmetrical or slightly oblique, inconspicuously nerved; fruiting invols 3–5 mm, 1-fld and 1 beaked, with a single series of short, sharp, erect spines near or above the middle; 2n=34, 36. Waste places; throughout our range, w. to the Pacific. (July) Aug.–Oct. (A. elatior; A. media)"
20–90 cm hoch. Stängel abstehend behaart. Blätter doppelt fiederschnittig, gestielt. Blütenköpfchen klein, eingeschlechtig, männliche mit 4–5 mm Durchmesser, in ährigen Trauben, nickend, mit je 5–12 Röhrenblüten, Hülle halbkugelig, kahl, Hüllblätte
Bushy annual herb, up to 2 m high. Ultimate leaf segments on average broader than 2 mm. Female heads several clustered in leaf axils below male heads. Flowers whitish, cream or yellowish.
Annual herb, up to 2 m high; coarse, bushy. Stems pilose when young, later rough-pubescent. Leaves mostly alternate; blade ovate in outline, pinnatisect or bipinnatisect, the ultimate segments oblong, narrowly obovate or elliptic, on average > 2 mm wide, lobe apices obtuse, acute or acuminate, lobe margins sometimes with 1 or 2 coarse teeth, pubescent on both surfaces, more densely so below, often drying very discolorous, aromatic or not; petiole ± 20 mm long. Heads unisexual; male heads small, drooping, in slender, leafless, terminal spikes up to ± 100 mm long, arranged in panicles, involucral bracts connate, cup-shaped, containing several, functionally male florets; female heads sessile, several clustered in leaf axils below male heads, involucral bracts connate, turbinate, enveloping cypsela, containing single female floret, corolla absent. Flowers: disc florets only, whitish; Jan.-Apr. Fruit with cypsela ovoid, enveloped in turbinate, involucral bracts, with 4-6 spines on shoulders. Pappus absent.
A coarse, bushy annual herb up to 2 m tall, stems pilose when young, later rough-pubescent. Leaves mostly alternate, pinnatisect or bipinnatisect, the ultimate segments lanceolate or elliptic, on average more than 2 mm broad, obtuse, acute or acuminate, sometimes with 1 or 2 coarse teeth, pubescent on both surfaces, more densely so below, often drying very discolorous, aromatic or not. Male heads small, drooping, in slender terminal spikes up to c. 10 cm long, arranged in panicles, the female heads clustered in the leaf axils below them.
Weed along roadsides, riverbanks and disturbed places.
Kalahari Deciduous Acacia-wooded Grassland; Dry Grassland. Weed of disturbed places.
|Ambrosia cun feglia d'artemisia||Raeto-Romance||CH|
|Ambroisie à feuilles d'armoise||French||CH|
|Ambrosia con foglie di artemisia||Italian||CH|