Youngia

Annuals, biennials [perennials], (10–)20–90+ cm; taprooted. Stems 1–5+, erect (often scapiform), usually branched distally, sometimes throughout, proximally glabrous, puberulent, or tomentose. Leaves all or mostly basal; petiolate (petiole bases often dilated, ± clasping); blades oblong or ovate to oblanceolate, margins usually pinnately lobed (± lyrate), ultimate margins denticulate. Heads (4–150) in corymbiform to paniculiform arrays. Peduncles (filiform) not distally inflated, seldom bracteate. Calyculi of 3–5+, deltate to ovate (membranous) bractlets. Involucres cylindric to campanulate, 2–3+ mm diam. Phyllaries usually 8 in 1–2 series, lanceolate to linear, ± equal (reflexed in fruit), margins ± scarious, apices obtuse to acute. Receptacles flat to convex, ± pitted, glabrous, epaleate. Florets 8–25+; corollas yellow, sometimes abaxially purplish (anther bases with linear, acute auricles). Cypselae ± reddish brown, ± fusiform and compressed [± terete], weakly or not beaked, ribs 11–13, ± spiculate to scabrellous on ribs; pappi (borne on discs at tips of cypselae) persistent (fragile) [falling], of 40–60+, basally coherent [distinct], white [yellowish or grayish], subequal, smooth to barbellulate bristles in ± 1 series. x = 5 or 8.

Distribution

Introduced; Asia, introduced also in South America, Europe, Africa, Pacific Islands, Australia.

Discussion

Species ca. 30 (1 in the flora).

Youngia americana Babcock (based on a specimen from Alaska) has not been used as an accepted name for plants in the flora area; it was treated as a synonym of Crepis nana var. lyratifolia (Turczaninow) Hultén by E. Hultén (1968).

Selected References

Babcock, E. B. and G. L. Stebbins. 1937. The genus Youngia. Publ. Carnegie Inst. Wash. 484.

Lower Taxa

Youngia japonica