24. Youngia japonica (Linnaeus) Candolle, Prodr. 7: 194. 1838.
黄鹌菜 huang an cai
Herbs usually 10-150 cm tall, annual. Stems solitary or few, erect, branched from base, middle, or only apically, glabrous or basally often ± hairy, ± leafy or leafless. Basal leaves ± oblanceolate, to 15(-25) × 4(-6) cm, lyrately pinnatipartite or pinnatisect, rarely not divided; glabrous or somewhat hairy, base attenuate into a longer or shorter narrowly winged to ± unwinged petiole-like portion, margin sinuate-dentate; lateral lobes few to many, ovate, rhombic, or elliptic, gradually smaller toward leaf base; terminal lobe ovate, ovate-lanceolate, or obovate, much larger than lateral ones, apex rounded to acute. Stem leaves similar to basal leaves, abruptly or gradually reduced to bracts upward on stem. Synflorescence corymbiform to paniculiform-corymbiform, usually with many to numerous capitula. Capitula with 10-20 florets; peduncle capillaceous. Involucre cylindric, 4-7 mm. Phyllaries abaxially glabrous; outer phyllaries ovate to triangular, longest less than 1.5 mm, apex acute; inner phyllaries adaxially appressed pubescent, midvein subapically plane, margin ± white scarious, apex acute. Anther tube dark green. Style branches yellow upon drying. Achene light brown to dark reddish or purplish brown, fusiform, 1.5-2.5 mm, ribs finely spiculate, apex strongly attenuate. Pappus white, 2.5-3.5 mm. Fl. and fr. Feb-Dec.
Mountain slopes, mountain valleys, ravines, forests, forest margins, grasslands, moist areas, by water, stream banks, trailsides, roadsides, disturbed places, densely grassy areas by houses or roads, field margins, as a weed in gardens and fields; below 100-4500 m. Anhui, Chongqing, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Shandong, Sichuan, Taiwan, Xizang, Yunnan, Zhejiang [present in all easterly and southerly neighboring countries; originating probably from China and introduced pantropically, extending into adjacent subtropical regions].
Youngia lyrata (= Y. pseudosenecio) and Y. longiflora (= Y. taiwaniana) are treated here as Y. japonica subsp. elstonii and Y. japonica subsp. longiflora, respectively, of a wider Y. japonica, following Babcock and Stebbins (Publ. Carnegie Inst. Washington 484: 97-98. 1937). While Y. japonica subsp. longiflora seems a fairly well-characterized taxon, the delimitation between Y. japonica subsp. japonica and Y. japonica subsp. elstonii appears questionable in view of frequent transitions and a probably scattered distribution pattern.
