4. Gamochaeta purpurea (Linnaeus) Cabrera, Bol. Soc. Argent. Bot. 9: 377. 1961.
合冠鼠麴草 he guan shu qu cao
Gnaphalium purpureum Linnaeus, Sp. Pl. 2: 854. 1753, nom. cons.; Gamochaeta rosacea (I. M. Johnston) Anderberg; Gnaphalium rosaceum I. M. Johnston.
Herbs, annual or biennial. Stems erect to decumbent-ascending, unbranched or 1 or 2 branched from base, 10-40 cm tall, densely but loosely pannose or pannose-tomentose. Leaves basal and cauline, basal and proximal cauline in rosettes, withered but persistent at anthesis; blades oblanceolate to spatulate, 1-6 cm × 5-14 mm, upper ones smaller, both surfaces usually bicolored, abaxially closely white pannose, adaxially usually sparsely arachnoid (basal cells of hairs persistent, expanded, glassy), sometimes glabrescent. Capitula initially in continuous spiciform arrays 1-4(-5) cm × (5-)10-15 mm, later interrupted, glomerules widely separated, bracteate, proximal often on relatively long peduncles. Involucre turbinate-cylindric, 3-4.5 mm, base sparsely arachnoid; phyllaries 4- or 5-seriate, outer ovate-triangular, length 1/3-2/3 of inner, apices acute-acuminate; inner triangular-lanceolate (usually striate), laminae purplish (in bud) to whitish or silvery (in fruit), apices acute (not apiculate). Bisexual florets 3 or 4. Corollas of all florets usually purplish distally. Achenes oblong, 0.6-0.7 mm. Pappus connate into a ring, ca. 2.5 mm. Fl. Apr-May. 2n = 14, 28.
Waste fields at low elevations. Introduced in Taiwan [native to North America; introduced in Asia, Europe, and South America].