Key to Hieracium

View taxon page for Hieracium

(For a list of species in Hieracium, use the above link.)

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Ligule white or orange

2. Ligule white; stolons 0; native of forests ..... H. albiflorum

2' Ligule orange; stolons present; weed of disturbed sites ..... [H. aurantiacum]

1' Ligule yellow

3. Leaf glabrous on 1 or both faces

4. Leaf glabrous abaxially, sparsely to ± densely long-hairy adaxially; phyllaries glabrous or sparsely glandular; flowers 6–12 ..... H. bolanderi (2)

4' Leaf glabrous; phyllaries long-hairy, branched-hairy, and black-glandular; flowers 20–60 ..... H. triste (2)

3' Leaf ± hairy on faces (glabrous in Hieracium scouleri)

5. Phyllaries generally without long, glandless hairs (occasionally long-hairy in Hieracium argutum), often minutely branched-hairy and/or glandular

6. Flowers 30–60 ..... H. parryi

6' Flowers 4–30

7. Flowers 15–30; 

involucre 

Group of bracts more or less held together as a unit, subtending a flower, fruit (acorn cup), or inflorescence.

7–9(12) mm; generally at least some leaves wavy-toothed (all entire); pappus ± white; c&s California ..... H. argutum (2)

7' Flowers generally 4–12(15); involucre (7)8–12 mm; leaves generally 

entire 

Having margins that are continuous and smooth (i.e., without teeth, lobes, etc.).

(minutely dentate); pappus tan to ± brown; KR, NCoR, CaRH

8. Peduncle glabrous or stalked-glandular; fruit ± 

urn-shaped 

Widening more or less abruptly at the base and then gradually or abruptly narrowed toward the tip.

..... H. bolanderi (2)

8' Peduncle branched-hairy; fruit ± 

cylindric 

Elongate, with parallel sides and, at any point, round in transverse section.

, not distally narrowed ..... H. greenei

5' Phyllaries with long, glandless hairs, occasionally also branched-hairy and/or glandular

9. Leaf faces minutely rough-hairy and/or stalked glandular ..... H. triste (2)

9' Leaf faces long-hairy, also sometimes branched-hairy (rarely glabrous in Hieracium scouleri)

10. Flowers 6–12(15); involucre ± cylindric to ± bell-shaped ..... H. horridum

10' Flowers 15–50; involucre obconic to bell-shaped

11. Some or all leaves wavy-toothed; c&s California ..... H. argutum (2)

11' Leaves all entire or some minutely 

dentate 

Having margins with sharp, relatively coarse teeth pointing outward, not tipward.

; n CA

12. Cauline leaves 0–3(5); pappus 4–6 mm ..... H. nudicaule

12' Cauline leaves generally (3)5–10+; pappus 6–7 mm ..... H. scouleri

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