Siberian Wormwood

Perennials, 5–15 cm (not cespitose), sometimes mildly aromatic. Stems 1–3, erect, reddish brown, simple, strigillose to spreading-hairy, or glabrous. Leaves basal (in rosettes, petioles to 12 cm) and cauline, greenish; blades (basal) 2. 3-pinnate, relatively deeply lobed (cauline sessile, 1–2-pinnately lobed to entire), faces sparsely hairy to pilose. Heads (10–70, spreading to nodding, peduncles 0 or to 10 mm) in spiciform arrays 2–5 × 0.5–1 or 8–18 × 1–4 cm. Involucres globose, 3–5 × 4–8 mm. Phyllaries (greenish or yellowish) elliptic (margins hyaline, brownish), glabrous or sparsely hairy. Florets: pistillate 6–8; bisexual 20–50; corollas yellowish or yellow to reddish-tinged, 1–2 mm, hairy (hairs tangled). Cypselae oblong, 0.5–1 mm, glabrous.

Perennial shrublet with several, upright, up to 50 – 60 (-90) cm tall, sparsely hairy and branched in upper part, ribbed stems from horizontally creeping to obliquely rising, ± woody rootstock. Leaves pitted glandular and glabrous-green or sparsely hairy above, densely hairy beneath, long petioled, exauriculate at the base, lamina oblong-elliptic, 3 – 12 x 1.5 – 5 (-8) cm, 2 -3-pinnatisect into oblong to very narrowly elliptic or lanceolate-linear, 4 – 5 x c. 1 mm, entire or serrate ultimate segments; upper leaves shortly petiolate to almost sessile; uppermost in the floral region unipinnatisect to entire, linear. Capitula many to numerous, shortly recurved pedunculate, broadly campanulate, c. 3 x 3 – 5 mm, approximate or not, nodding in a narrow or wide, 10 – 15 x 4 – 8 cm, slightly to much branched or simple panicle. Involucre 3-4-seriate, phyllaries laxly imbricate, glabrous or nearly so, outermost oblong-oval, greenish, narrowly scarious margined, inner ones narrowly elliptic, broadly scarious margined, obtuse. Receptacle hemispherical, glabrous. Florets yellow, 48 – 52, all fertile; marginal florets 10-12, with narrowly tubular, glandulose, bidentate corolla; disc-florets 38-42, with cone-like, 5-toothed, glandular corolla. Cypselas oblong, finely longitudinally striate.

Distribution: S. E. Europe, Central Asia, Russia, Mongolia, Chiina, Japan.

Fl. Per.: August-September.