Hieracium L.
Perennial rhizomatous herbs; stolons present or 0. Hairs stellate, plumose, simple and eglandular, and glandular, in various proportions. Stems branching or scapose. Lvs simple, usually toothed, usually basal and cauline, or all basal, sometimes basal rosette 0. Capitula solitary or paired or in lax to compact cymes or corymbose panicles. Involucral bracts narrowly triangular to linear, usually hairy; outer bracts < inner; inner bracts in several imbricate series. Receptacle areolate, the margins of areoles glabrous and usually dentate or fimbriate; scales 0. Corolla ligulate, usually yellow, rarely orange, sometimes with red or pink stripe on outer face. Style branches filiform, yellow or discoloured. Achenes numerous, dark, cylindric, 10-ribbed, not beaked; pappus bristles in 1 row or partly in 2 rows, usually dirty white, > achenes, often unequal, simple, free at base.
SYNOPSIS
may be neatly divided into several subgenera although arguments for accepting these at generic rank are not all convincing. Two of these, subgen. and subgen. , are represented in N.Z.:
- A. Subgen. Hieracium.
- Mostly obligate apomicts. Stolons 0. Lvs entire to deeply dentate; at least the basal lvs usually petiolate. Achenes 3-5 mm long, the ribs apically confluent into an obscure ring. Pappus partly in 2 rows, the hairs unequal:
- 1. *argillaceum group 4. *lepidulum 5. *murorum 7. *pollichiae 9. *sabaudum
- B. Subgen. Pilosella.
- Plants sexual or partly apomictic. Stolons usually present. Lvs entire to slightly denticulate; petiole 0 or indistinct. Achenes up to 2.5 mm long, the ribs shortly protruding to give a crenulate apex to the achene. Pappus strictly in 1 row, a few hairs much < the others:
- 2. *aurantiacum 3. *caespitosum 6. *pilosella 8. *praealtum 10. *× stoloniflorum
Key
c. 1000 spp. (or c. 5000 spp. if apomictic microspp. included), temperate regions (except Australasia) and tropical mountains. Naturalised spp. 9 and 1 hybrid.
African spp. sometimes included in Hieracium may be better placed in Tolpis, and S. American spp. in Crepis, according to Sell, P. D. and West, C., in Fl. Turkey 5 : 697 (1975).