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hound-tongue hawkweed, hounds tongue hawkweed, hounds-tongue hawkweed (var. griseum), Scouler's hawkweed, Scouler's woollyweed, western hawkweed, western hawkweed (var. albertinum), woolly weed, woolly-weed (var. scouleri)

hawkweed, épervière

Habit Plants (15–)35–60+ cm. Perennials, (5–)20–150+ cm; taprooted (rootstocks sometimes woody, branched; stolons produced in some taxa).
Stems

proximally usually piloso-hirsute (hairs 1–8+ mm) and stellate-pubescent, sometimes glabrous, distally usually piloso-hirsute (hairs 1–8+ mm) and stellate-pubescent, rarely stipitate-glandular as well, sometimes glabrous.

usually 1, usually erect, usually branched distally, sometimes throughout, sometimes scapiform, glabrous or hairy (induments often complex, see discussion).

Leaves

basal 0(–5+), cauline (3–)5–10+;

blades lanceolate, oblanceolate or narrowly oblong to elliptic, 50–100(–200) × 10–25(–35+) mm, lengths (3–)4–8+ times widths, bases cuneate, margins entire or denticulate, apices obtuse to acute, faces usually piloso-hirsute (hairs 1–5+ mm) and stellate-pubescent, rarely glabrous.

basal, basal and cauline, or cauline; petiolate or sessile;

blades mostly elliptic, lanceolate, oblanceolate, oblong, or spatulate, margins entire, denticulate, or dentate [laciniate to pinnatifid] (faces glabrous or hairy, induments often complex, see discussion).

Peduncles

usually stellate-pubescent, sometimes piloso-hirsute and/or stipitate-glandular as well, rarely glabrous.

(terminal and axillary) not inflated, often bracteate.

Involucres

campanulate, 8–10 mm.

hemispheric or campanulate to cylindric, 3–9[–12+] mm diam.

Receptacles

flat, pitted, glabrous, epaleate.

Florets

20–45+;

corollas yellow, 10–12 mm.

6–150+;

corollas usually yellow, sometimes white or ochroleucous, sometimes tinged with cyan or red, rarely orange (then often drying scarlet or purplish).

Phyllaries

12–21+, apices rounded to acute, abaxial faces piloso-hirsute, stellate-pubescent, and stipitate-glandular.

5–21(–40+) in 2+ series, lanceolate to linear, subequal to unequal (reflexed in fruit), margins usually little, if at all, scarious, apices obtuse to acute or acuminate.

Calyculi

bractlets 5–13+.

0 or of 3–13(–16+), deltate to lanceolate or linear bractlets (in 1–2+ series; sometimes intergrading with phyllaries).

Heads

(3–)9–25+ in corymbiform to thyrsiform arrays.

borne singly or in corymbiform, paniculiform, thyrsiform, umbelliform, or nearly racemiform arrays.

Cypselae

(red-brown or black) columnar, ca. 3 mm;

pappi of 32–40+, white or stramineous bristles in ± 2 series, 6–7 mm.

usually red-brown or black (tan in H. horridum), usually ± columnar or prismatic, sometimes ± urceolate (slightly bulbous proximally and narrower distally) or nearly fusiform, not distinctly beaked, ribs (or grooves) usually 10, faces glabrous;

pappi persistent (fragile), of 20–80+, distinct, white, sordid, stramineous, or rufous, ± equal or unequal, barbellulate bristles in 1–2+ series.

x

= 9.

Hieracium scouleri

Hieracium

Phenology Flowering Jun–Sep.
Habitat Disturbed sites, openings in pine forests and sagebrush, borders of meadows
Elevation 400–3000 m (1300–9800 ft)
Distribution
from FNA
CA; ID; MT; NV; OR; UT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
from USDA
North America; Mexico; Central America; South America; Europe; Asia; Africa
[BONAP county map]
Discussion

Species 250–1000+ (36 in the flora).

Most plants referable to Hieracium are apomictic (reproducing from asexually produced seeds). Apomictic reproduction often results in perpetuation of morphologic variants at populational and regional levels. Temptation to name such variants as species has proven irresistible to some botanists; upward of 9,000 species names have been published in Hieracium. Circumscriptions of “species” in Hieracium seem to be more artificial than in most genera of composites. Under these circumstances, I feel it would be irresponsible to recognize any infraspecific taxa here. For the most part, the “species” recognized here are those that have been recognized in local and regional floras of the past 50 or so years. Accepted names and/or changes in synomymies for some species reflect changes suggested by J. H. Beaman (1990), A. Cronquist (1980), and E. G. Voss (1972–1996, vol. 3).

I have maintained a traditional generic circumscription of Hieracium. Some other botanists exclude some species (including numbers 1–6 here) from Hieracium and treat them in Pilosella Hill, which differs from Hieracium in having stolons often produced, ribs of cypselae slightly projecting distally, and bristles of the pappi in one series.

For Greenland, T. W. Böcher et al. (1968) reported 18 species of Hieracium: 16 said to be endemic to Greenland plus H. alpinum Linnaeus (known from Greenland and Eurasia) and H. groenlandicum Arvet-Touvet (= H. vulgatum Fries; known from Greenland and continental North America). Following H. J. Scoggan (1978–1979, part 4), I have placed 15 names of Greenland “endemics” as synonyms of other names. The type of the 16th “endemic,” H. trigonophorum Oskarsson, is probably conspecific with that of H. alpinum.

In my key and descriptions, “piloso-hirsute” refers to surfaces with scattered to crowded, tapered, whiplike, straight or curly, smooth to ± barbellate hairs mostly (0.5–)2–8(–15+) mm (sometimes called “setae”); “stellate-pubescent” refers to surfaces with scattered to crowded, ± dendritically branched (often called, but seldom truly, “stellate”) hairs mostly 0.05–0.2+ mm (such surfaces are sometimes described as “floccose”); and “stipitate-glandular” refers to surfaces with scattered to crowded gland-tipped hairs mostly 0.2–0.8(–1.2+) mm. Surfaces of stems, leaves, peduncles, and phyllaries may be glabrous or may bear one, two, or all three of the types of hairs mentioned here; other induments are seldom encountered in hieraciums of the flora area.

Given the complexity of the reproductive modes among the plants and the likelihood of misidentifications of vouchers, I have not included chromosome numbers for species. Sexual hieraciums are usually diploids (2n = 18) and the apomictic hieraciums are usually triploids (2n = 27).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Corollas yellow (often each with abaxial red stripe) or orange (drying scarlet to purple); cypselae 1–2.5 mm; pappi of 25–40+, white or sordid bristles in 1 series (plants sometimes stoloniferous)
→ 2
1. Corollas yellow or ochroleucous to white (pinkish in H. carneum); cypselae (2–)2.5–7 mm; pappi of (30–)40–80, white or stramineous to sordid bristles in 1–2+ series (plants not stoloniferous)
→ 8
2. Leaf blades elliptic to ± oblanceolate, lengths 2–4(–6+) times widths; heads usually borne singly
H. pilosella
2. Leaf blades obovate or oblanceolate to spatulate or lanceolate, lengths (2–)3–8+ times widths; heads usually (2–)5–30+ in corymbiform to paniculiform or ± umbelliform arrays, rarely borne singly
→ 3
3. Corollas orange (drying scarlet to purple)
H. aurantiacum
3. Corollas yellow (often each with abaxial red stripe)
→ 4
4. Heads (1–)2–5+, in ± umbelliform arrays
→ 5
4. Heads (2–)10–30+, usually in corymbiform to paniculiform, sometimes ± umbelliform, arrays (rarely borne singly in H. triste)
→ 6
5. Stems proximally piloso-hirsute (hairs 2–4+ mm) and stellate-pubescent; involucres (9–)12–13 mm
H. flagellare
5. Stems proximally piloso-hirsute (hairs 1–2+ mm), sometimes stipitate- glandular as well; involucres 6–8 mm
H. lactucella
6. Leaves usually piloso-hirsute and stellate-pubescent; corollas 8–12+ mm.
H. caespitosum
6. Leaves usually glabrous, sometimes piloso-hirsute (on midribs and at margins) or scabrellous and/or stipitate-glandular (not both piloso-hirsute and stellate-pubescent); corollas 5–9 mm
→ 7
7. Leaves glabrous or piloso-hirsute (on midribs and at margins); involucres 5–6(–7) mm; florets (40–)60–80+; pappi 3–4 mm
H. piloselloides
7. Leaves glabrous or scabrellous and/or stipitate-glandular; involucres (6–)7–10 mm; florets 20–60+; pappi 4–5 mm
H. triste
8. Cypselae ± urceolate (slightly bulbous in proximal 1/3–1/2+, narrower in distal 1/3–1/2+, not distinctly beaked)
→ 9
8. Cypselae columnar or prismatic (little, if at all, bulbous proximally and narrower in distal 1/3–1/2)
→ 16
9. Corollas yellow
→ 10
9. Corollas usually ochroleucous to whitish, sometimes pale yellow or pinkish
→ 13
10. Cauline leaves 0–3; cypselae 5–5.5 mm
H. bolanderi
10. Cauline leaves (1–)3–12+; cypselae 3–4.5 mm
→ 11
11. Stems proximally piloso-hirsute (hairs 6–15+ mm); blades of cauline leaves mostly oblanceolate, lengths 4–7+ times widths
H. longipilum
11. Stems proximally piloso-hirsute (hairs 1–4+ mm); blades of cauline leaves elliptic to obovate or oblanceolate, lengths 2–4+ times widths
→ 12
12. Heads in ± thyrsiform arrays (lengths of arrays 3–6+ times diams.); phyllaries usually glabrous or stellate-pubescent, sometimes stipitate- glandular; florets 12–20+; corollas 8–9 mm
H. gronovii
12. Heads in ± corymbiform arrays (lengths of arrays ± 2 times diams.); phyllaries stellate-pubescent and stipitate-glandular; florets 20–50+; corollas 10–12+ mm
H. megacephalon
13. Cauline leaves 0–1(–3+); involucres (10–)12–15+ mm; phyllaries usually piloso-hirsute (hairs 1–3+ mm) and stellate-pubescent, sometimes stipitate-glandular as well
H. fendleri
13. Cauline leaves (0–)3–8+; involucres 7–11 mm; phyllaries glabrous or stellate-pubescent and/or stipitate-glandular (not piloso-hirsute)
→ 14
14. Leaves glabrous or piloso-hirsute (hairs 3–6+ mm); corollas whitish to pinkish; pappi 4–5 mm
H. carneum
14. Leaves glabrous or piloso-hirsute (hairs 0.5–2+ mm); corollas ochroleucous to whitish or pale yellow; pappi 5–6 mm
→ 15
15. Leaf blades elliptic to oblanceolate, 30–85 × 16–35 mm, lengths 2.5–5 times widths; florets 25–40; cypselae 3.5–4.5(–5+) mm.
H. crepidispermum
15. Leaf blades oblanceolate to lanceolate, 35–120 × 10–18 mm, lengths 4–10+ times widths; florets 15–25+; cypselae 5–6 mm
H. brevipilum
16. Leaves all or mostly cauline (basal leaves usually wanting or withered, cauline leaves usually 6–45+) at flowering
→ 17
16. Leaves all basal or basal and cauline (basal leaves usually 3–12+, cauline leaves usually 0–8+) at flowering
→ 29
17. Corollas white, ochroleucous, or pale yellow
→ 18
17. Corollas yellow
→ 19
18. Involucres 6–7 mm; corollas 5–8 mm; cypselae 2–2.5 mm; pappi 4–5 m.
H. paniculatum
18. Involucres (7–)8–10(–11) mm; corollas 9–10 mm; cypselae 2.5–4 mm; pappi (4–)5–7 mm
H. albiflorum
19. Phyllaries piloso-hirsute, sometimes stellate-pubescent and/or stipitate-glandular as well
→ 20
19. Phyllaries usually stellate-pubescent and/or stipitate-glandular (not piloso-hirsute)
→ 23
20. Stems usually glabrous, sometimes distally stellate-pubescent; leaves usually glabrous, sometimes scabrous near distal margins (not piloso- hirsute)
H. umbellatum
20. Stems usually piloso-hirsute, sometimes stellate-pubescent as well, sometimes glabrous (H. scouleri); leaves piloso-hirsute, sometimes glabrous (H. scouleri)
→ 21
21. Leaf blades: lengths (3–)4–8+ times widths; pappi 6–7 mm
H. scouleri
21. Leaf blades: lengths 2.5–5+ times widths; pappi 5–6 mm
→ 22
22. Involucres 7–10 (× 4–5) mm; phyllaries piloso-hirsute (hairs 2–5 mm) and stellate-pubescent; florets 12–24+
H. longiberbe
22. Involucres 8–12 (× 6–10) mm; phyllaries piloso-hirsute (hairs 2–5 mm) and stellate-pubescent and stipitate-glandular; florets 25–40+
H. schultzii
23. Peduncles stipitate-glandular, sometimes piloso-hirsute and/or stellate-pubescent as well
→ 24
23. Peduncles piloso-hirsute and/or stellate-pubescent (not stipitate-glandular)
→ 26
24. Leaves: margins of some or all sinuately toothed; florets 15–30+
H. argutum
24. Leaves: margins usually entire, sometimes denticulate; florets 30–60+
→ 25
25. Peduncles stipitate-glandular (not stellate-pubescent); involucres 10–12+ mm; phyllaries stipitate-glandular (not stellate-pubescent)
H. parryi
25. Peduncles stellate-pubescent and stipitate-glandular; involucres 7–9 mm; phyllaries stellate-pubescent and stipitate- glandular
H. scabrum
26. Stems distally usually glabrous, sometimes stellate-pubescent (not piloso-hirsute); leaf lengths (3–)5–10(–15) times widths
→ 27
26. Stems distally piloso-hirsute, sometimes stellate-pubescent as well; leaf lengths 2–4 times widths
→ 28
27. Florets 15–30+; pappi white, 3.5–5 mm (California)
H. argutum
27. Florets 30–80+; pappi stramineous to sordid, 6–7 mm
H. umbellatum
28. Leaves abaxially usually glabrous, sometimes piloso-hirsute on midribs; involucres 10–15 mm; phyllaries 25–35 (apices acuminate-caudate)
H. robinsonii
28. Leaves abaxially piloso-hirsute (bases of hairs swollen); involu- cres 8–9 mm; phyllaries ca. 21 (apices rounded)
H. sabaudum
29. Phyllaries usually stellate-pubescent and/or stipitate-glandular (rarely, if ever, piloso-hirsute), rarely glabrous
→ 30
29. Phyllaries usually piloso-hirsute, often stellate-pubescent and/or stipitate-glandular as well, rarely glabrous
→ 38
30. Florets 4–15+ (15–30+ in 35 Hieracium argutum with sinuately toothed leaf margins; California).
→ 31
30. Florets 30–80+
→ 32
31. Stems proximally piloso-hirsute (hairs at bases of stems 5–8+ mm, often curled and tangled); involucres (7–)8–9 mm; pappi 4–5+ mm
H. pringlei
31. Stems proximally stellate-pubescent, rarely piloso-hirsute (hairs at bases of stems 1–3+ mm, not or rarely curled and tangled); involucres 9–12 mm; pappi 7–9 mm
H. greenei
32. Margins of some or all leaves entire or denticulate
→ 33
32. Margins of some or all leaves usually dentate
→ 35
33. Stems distally piloso-hirsute and stipitate-glandular
H. parryi
33. Stems distally usually glabrous or stellate-pubescent, sometimes piloso-hirsute (not stipitate-glandular)
→ 34
34. Leaf blades oblanceolate to spatulate, lengths 3–5 times widths; peduncles stellate-pubescent and stipitate-glandular; pappi 6–7 mm.
H. traillii
34. Leaf blades elliptic or obovate to oblanceolate, lengths 2–3(–4) times widths; peduncles usually stipitate-glandular, rarely glabrous or glabrate (not stellate-pubescent); pappi 4–5 mm
H. venosum
35. Leaf blades spatulate or oblanceolate to lance-linear, lengths 5–10(–15+) widths (California)
H. argutum
35. Leaf blades oblong or elliptic to lance-elliptic or lanceolate, lengths 1.5–4+ widths
→ 36
36. Basal leaves 2–4, cauline (2–)4–10, abaxial faces usually glabrous, sometimes piloso-hirsute on midribs; involucres 10–15 mm; pappi ca. 6 mm.
H. robinsonii
36. Basal leaves 3–8+, cauline (0–)1–5+, abaxial faces usually piloso-hirsute, sometimes stellate-pubescent as well; involucres 8–10 mm; pappi 4–5 mm
→ 37
37. Leaf blades ± elliptic, lengths 1.5–3+ widths, bases usually rounded to truncate, apices ± obtuse (apiculate); corollas 12–13(–16) mm.
H. murorum
37. Leaf blades lance-elliptic to lanceolate, lengths 2.5–4 widths, bases usually cuneate, sometimes rounded to truncate, apices acute; corollas 13–18 mm
H. vulgatum
38. Heads 1(–2+); involucres 13–18+ mm (Greenland)
H. alpinum
38. Heads (1–)3–30(–60+); involucres 6–8(–11) mm
→ 39
39. Leaf blades obovate to spatulate or oblanceolate, (15–)25–40(–60+) mm, lengths 2–3+ times widths, apices rounded to obtuse (often apiculate), abaxial faces usually glabrous, sometimes scabrellous and/or stipitate-glandular (not piloso-hirsute)
H. triste
39. Leaf blades elliptic, lance-linear, lanceolate, oblanceolate, oblong, or spatulate (15–)50–100(–300) mm, lengths (2–)4–15+ times widths, apices usually rounded, obtuse, or acute (not apiculate), abaxial faces usually piloso-hirsute (hairs 1–7+ mm), sometimes stellate-pubescent as well, rarely glabrous (some H. scouleri, H. albiflorum, H. nudicaule)
→ 40
40. Peduncles usually glabrous, sometimes stipitate-glandular (not stellate- pubescent); corollas white
H. albiflorum
40. Peduncles usually stellate-pubescent and/or stipitate-glandular, sometimes piloso-hirsute as well, rarely glabrous (some H. scouleri, H. venosum); corollas yellow (sometimes pale in H. venosum)
→ 41
41. Involucres ± cylindric (6–9 × 3–4 mm); florets 6–12(–15+); cypselae 3–3.5 mm (tan to red- brown)
H. horridum
41. Involucres campanulate, hemispheric, obconic, or turbinate (6–10+ × 4–9+ mm); florets (15–)20–60+; cypselae 2–4 mm (usually black, sometimes red-brown)
→ 42
42. Cauline leaves 0–1(–2); florets 30–60+ (mostly e of Mississippi River)
→ 43
42. Cauline leaves 0–10+; florets 15–45+ (w of Mississippi River)
→ 44
43. Peduncles usually stipitate-glandular, rarely glabrous or glabrate; pappi 4–5 mm
H. venosum
43. Peduncles stipitate-glandular and stellate-pubescent; pappi 6–7 mm
H. traillii
44. Faces of leaf blades piloso-hirsute; florets 20–24; corollas 6–9 mm
H. abscissum
44. Faces of leaf blades piloso-hirsute and stellate-pubescent; florets 15–45+; corollas 8–12 mm
→ 45
45. Margins of some or all leaf blades sinuately toothed
H. argutum
45. Margins of leaf blades usually entire, sometimes denticulate
→ 46
46. Cauline leaves (3–)5–10+; pappi 6–7 mm
H. scouleri
46. Cauline leaves 0–3(–5); pappi 4–6 mm
H. nudicaule
Source FNA vol. 19, p. 289. FNA vol. 19, p. 278. Author: John L. Strother.
Parent taxa Asteraceae > tribe Cichorieae > Hieracium Asteraceae > tribe Cichorieae
Sibling taxa
H. abscissum, H. albiflorum, H. alpinum, H. argutum, H. aurantiacum, H. bolanderi, H. brevipilum, H. caespitosum, H. carneum, H. crepidispermum, H. fendleri, H. flagellare, H. greenei, H. gronovii, H. horridum, H. lactucella, H. longiberbe, H. longipilum, H. megacephalon, H. murorum, H. nudicaule, H. paniculatum, H. parryi, H. pilosella, H. piloselloides, H. pringlei, H. robinsonii, H. sabaudum, H. scabrum, H. schultzii, H. traillii, H. triste, H. umbellatum, H. venosum, H. vulgatum
Subordinate taxa
H. abscissum, H. albiflorum, H. alpinum, H. argutum, H. aurantiacum, H. bolanderi, H. brevipilum, H. caespitosum, H. carneum, H. crepidispermum, H. fendleri, H. flagellare, H. greenei, H. gronovii, H. horridum, H. lactucella, H. longiberbe, H. longipilum, H. megacephalon, H. murorum, H. nudicaule, H. paniculatum, H. parryi, H. pilosella, H. piloselloides, H. pringlei, H. robinsonii, H. sabaudum, H. scabrum, H. schultzii, H. scouleri, H. traillii, H. triste, H. umbellatum, H. venosum, H. vulgatum
Synonyms H. absonum, H. albertinum, H. chapacanum, H. cynoglossoides, H. scouleri var. albertinum, H. scouleri var. griseum Pilosella
Name authority Hooker: Fl. Bor.-Amer. 1: 298. (1833) Linnaeus: Sp. Pl. 2: 799. (1753): Gen. Pl. ed. 5, 350. (1754)
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