Jepson eFlora: Key page
Vascular Plants of California
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Key to Erigeron

View taxon page for Erigeron

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

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

1. Heads discoid, disciform, or inconspicuously radiaterays 0 to barely exceeding 

2. Pistillate flowers present

3. Pistillate flowers of 2 kinds, those in outer zone with rays 3–4.5 mm, those in inner zone without rays ..... E. nivalis (2)

3' Pistillate flowers ± all alike, generally not in 2 zones

4. Heads 1; stem 

5. Annual or biennialpappus bristles 6–9(12) ..... E. divergens (3)

5' Perennial herb; pappus bristles 12–30

6. Leaves (1)2–3(4)-ternately dissected ..... E. compositus (2)

6' Leaves 

7. Stem minutely glandular; disk corolla generally abruptly inflated to throat ..... E. aphanactis var. congestus

7' Stem glandless; disk corolla narrowly 

8. Plant 3–12 cm, from woody taproot or short-branched ; MP ..... E. chrysopsidis var. austiniae

8' Plant 15–40 cm, from taproot and slender-branched, rhizome-like caudex; n&c NCo, n CCo ..... E. supplex (2)

4' Heads 1–many; stem often branched

9. Rays 1–3 mm

10. Inflorescence panicle-like, heads many; rays <= 1 mm; involucre glabrous or sparsely  to minutely bristly; central colored part of middle phyllaries resin-filled, ± red-brown when dry ..... E. canadensis (3)

10' Inflorescence generally raceme-like, heads 1–12; rays 2–3 mm; involucre ± rough-hairy; central colored part of middle phyllaries not resin-filled, not red-brown when dry ..... E. lonchophyllus (2)

9' Rays 0–1 mm

11. Central stem and axes of stiffly  branches generally strongly dominant; inflorescence generally raceme- or panicle-like, often many-headed; disk flowers 6–25

12. Central stem often overtopped by distal branches in age; plant ± gray-hairy; heads ± long-peduncled, generally in raceme-like clusters; receptacle (2.5)3–5 mm diam in fruitpistillate flowers 60–150+; phyllaries generally minutely bristly and/or densely strigose; pappus 3–4+ mm ..... E. bonariensis

12' Central stem generally exceeding distal branches in age; plant green, glabrous to hairy; heads ± short-peduncled in panicle-like clusters; receptacle 1–3 mm diam in fruit; pistillate flowers 20–90+; phyllaries glabrous to densely strigose or densely bristly; pappus 2–3(4) mm

13. Leaf ± long-bristly-ciliate; phyllaries generally glabrous, occasionally sparsely strigose; central colored part of middle phyllaries narrower than light-colored margin, resin-filled, ± red-brown when dry; ray 0.3–1 mm; disk corolla generally 4-lobed; fruit uniformly pale tan to light gray-brown ..... E. canadensis (3)

13' Leaf margin generally ± fine-strigose; phyllaries glabrous to densely strigose or spreading-hairy; central part of middle phyllaries generally wider than lighter margin, not red-brown or resin-filled when dry; ray 0–0.3 mm; disk corolla generally 5-lobed; fruit pale tan, generally some in  with ± red veins ..... E. sumatrensis

11' Central stem and axes of ascending branches not strongly dominant, plant ± openly branched; inflorescence ± cyme-like, often 1–few-headed; disk flowers generally >= 25

14. Perennial herb; pappus bristles 12–17 ..... E. aphanactis var. aphanactis

14' Annual, biennial or short-lived  herb; pappus bristles 6–9(12) or 15–20

15. Pappus bristles 15–20; biennial or short-lived perennial herb ..... E. calvus

15' Pappus bristles 6–9(12); annual or biennial ..... E. divergens (3)

2' Pistillate flowers 0

16. Basal leaves present at flower; cauline leaves generally much-reduced or 0 distally

17' Caudex branched

18. Stem ascending, 15–40 cm, occasionally sparsely spreading-hairy; caudex branches slender, rhizome-like;  leaves  to oblanceolate to spoon-shaped ..... E. supplex (2)

18' Stem , 4–15 cm, ± glabrous to densely strigose; caudex branches short, stout; basal leaves ±  ..... E. bloomeri

19. Herbage and phyllaries strigose ..... var. bloomeri

19' Herbage and phyllaries ± glabrous ..... var. nudatus

16' Basal leaves 0 at flower; cauline leaves generally evenly sized and spaced

20. Glandless stem hairs ± 

21. Stem hairs dense, short, stiff, slightly , ± gray ..... E. inornatus var. keilii

21' Stem hairs sparse to dense, long, ± crinkly-spreading, white

22. Stem 30–90 cm, ascending to erect; leaves 20–40 mm; involucre 12–15 mm diam ..... E. biolettii (2)

22' Stem 5–30 cm,  to ascending; leaves 7–25 mm; involucre 7–15 mm diam

23. Inner phyllaries 3.5–5 mm ..... E. miser

23' Inner phyllaries 5.5–7 mm ..... E. petrophilus

24. Herbage ± glandless; hairs stiff, straight or curved ..... var. viscidulus

24' Herbage densely glandular; glandless hairs generally loose, often crinkly

25. Phyllary tips obviously widened and ± purple ..... var. petrophilus

25' Phyllary tips not widened or purple ..... var. sierrensis

20' Glandless stem hairs 0–sparse, 

26. Phyllaries generally glabrous ..... E. inornatus (in part)

27. Stem 10–20 cm, decumbent to ascending; proximally ± reflexed-hairy; proximal and middle  blades and margins stiffly spreading-hairy and -ciliate; inner phyllaries 5–6.5 mm ..... var. calidipetris

27' Stem 30–90 cm, ascending; proximally ± glabrous or appressed-hairy; proximal and middle leaf blades and margins generally short-strigose or ± glabrous; inner phyllaries 4.5–5.5 mm ..... var. inornatus

26' Phyllaries glandular (sometimes also with sparse, glandless hairs)

28. Herbage glandular; leaf narrowly oblanceolate ..... E. biolettii (2)

28' Herbage glandless; leaf thread-like to oblanceolate

29. Leaf ± oblanceolate; stem long-ascending from woody taproot ..... E. inornatus var. inornatus

29' Leaf thread-like to linear; stem from stout woody caudex or thin, rhizome-like caudex branches

30. Stem 30–90 cm, many, from stout woody caudex ..... E. greenei

30' Stem 8–20(30) cm, 1, from slender, rhizome-like caudex branches ..... E. reductus

31. Phyllary tips generally ± purple (variable n SnFrB); pappus bristles 38–61 ..... var. angustatus

31' Phyllary tips ± green; pappus bristles 20–30 ..... var. reductus

1' Heads conspicuously radiate, rays exceeding to much-exceeding involucre

32. Pistillate flowers of 2 kinds, those in outer zone with rays 3–4.5 mm, those in inner zone without rays ..... E. nivalis (2)

32' Pistillate flowers all alike, not in 2 zones

33. Rays 1–3 mm

34. Inflorescence panicle-like, heads many; rays <= 1 mm; involucre glabrous or sparsely strigose to minutely bristly; central colored part of middle phyllaries resin-filled, ± red-brown when dry ..... E. canadensis (3)

34' Inflorescence generally raceme-like, heads 1–12; rays 2–3 mm; involucre ± rough-hairy; central colored part of middle phyllaries not resin-filled, not red-brown when dry ..... E. lonchophyllus (2)

33' Rays 4–25 mm

35. Annual (biennial to short-lived perennial herb) from slender taproot or shallow  roots (see also Erigeron philadelphicus var. philadelphus)

36. Ray flower pappus 0; plant fibrous-rooted

37. Leaves generally coarsely toothed; stem hairs sparsely spreading or appressed ..... E. annuus

37' Leaves generally entire; stem hairs appressed ..... E. strigosus var. strigosus

36' Ray flower pappus present; plant taprooted (Erigeron flagellaris generally fibrous-rooted)

38. Stem hairs appressed; plant with herbaceous, leafy runners ..... E. flagellaris

38' Stem hairs spreading; plant without runners

39. Annual or biennial; KR, CaRH, SN (exc Teh), s SCoRO, SnGb, SnBr, SnJt, GB, D ..... E. divergens (3)

39' Perennial (but flowering in 1st year); e NCoRI, CaRF, n SNF, ScV (Sutter Buttes), W&I ..... E. incomptus (2)

35' Perennial herb or subshrub from woody taproot, branched caudex, or 

40. Leaves 1–4-ternately dissected

41. Leaves generally (1)2–3(4)-ternately dissected; ray < 1 mm wide; caudex branches short, thick, ascending ..... E. compositus (2)

41' Leaves deeply 3-lobed at tip; ray 1–2 mm wide; caudex branches thin, rhizome-like ..... E. vagus

40' Leaves entire to shallowly toothed

42. Leaf bases hardened, white-shiny, expanded, enclosing proximal stem

43. Caudex branches thick, leaf bases persistent; rays yellow ..... E. linearis

43' Caudex branches slender, rhizome-like, leaf bases not persistent; rays white, pink to blue or lavender

44. Involucre 13–18 mm diam; basal leaves generally 2–5 mm wide; pappus bristles 25–40; phyllary hairs spreading; >= 2100 m; CaRH, n&c SNH ..... E. barbellulatus

44' Involucre 6–11 mm diam; basal leaves generally 0.5–1 mm wide; pappus bristles 20–30; phyllary hairs appressed; 1000–2200 m; MP ..... E. elegantulus

42' Leaf bases ± thin, not hardened, barely or not expanded

45. Fruit ribs 4–8; herbage generally ± silvery, hairs dense, appressed

46. Fruit ribs 6–8; basal leaves tufted, persistent ..... E. argentatus

46' Fruit ribs 4(6); basal leaves generally 0 at flower

47. Outer pappus conspicuous, of bristles or narrow scales; stem silvery-white ..... E. parishii

47' Outer pappus inconspicuous; stem gray-green, densely strigose ..... E. utahensis

45' Fruit ribs generally 2 (if more, herbage not silvery)

48. Phyllaries strongly graduated; leaves entire, not clasping, basal 0, cauline generally evenly sized and spaced

49. Stem minutely glandular ..... E. aequifolius

49' Stem generally not glandular

50. Stem hairs dense, minutely curled- or bent; fruit glabrous ..... E. blochmaniae

50' Stem hairs 0 to dense, straight, stiffly spreading to ± reflexed or appressed; fruit sparsely strigose

51. Stem hairs dense, stiffly spreading, generally slightly reflexed

52. Herbage hairs 0.5–1 mm; phyllaries densely minutely glandular, inner phyllary tips widely white-thick-margined; stem often from woody basal offsets and roots ..... E. klamathensis

52' Herbage hairs <= 0.1–0.4 mm; phyllaries glandular or glandless, inner phyllary tips green; stem from ± slender, rhizome-like bases ..... E. breweri

53. Phyllaries densely glandular, glandless hairs 0 or very sparse

54. Stem generally >= 20 cm, ascending to erect; leaves generally >= 15 mm ..... var. breweri

54' Stem 7–15 cm,  to decumbent; leaves 5–12 mm ..... var. jacinteus

53' Phyllaries not or barely glandular, glandless hairs prominent

55. Stem 20–30 cm, wiry, brittle; phyllary hairs long, thick-based, stiffly spreading, translucent (also some glandular) ..... var. porphyreticus

55' Stem 30–75 cm, not wiry or brittle; phyllary hairs short, white, ± appressed, glandless

56. Phyllary hairs thin-based, ± appressed, slightly less dense on inner phyllaries ..... var. bisanctus

56' Phyllary hairs thick-based, ascending, much less dense on middle and inner phyllaries ..... var. covillei

51' Stem hairs ± 0 or sparse, appressed

57. Stem prostrate to ± erect, from slender rhizome ..... E. elmeri

57' Stem decumbent to erect, from woody taproot

58. Ray flowers 9–13; leaf , hairs thin-based; phyllaries with minute glandless hairs and densely minutely glandular ..... E. serpentinus

58' Ray flowers 15–60; leaf ciliate, hairs thick-based; phyllaries glandular or glandless

59. Phyllaries 0.8–1 mm wide, margins generally widely scarious, minutely but prominently glandular ..... E. foliosus (in part)

60. Phyllary hairs all glandular; leaves generally 1–2 mm wide ..... var. confinis

60' Phyllary hairs glandular and glandless, ± densely bristly-strigose; leaves generally 2–4 mm wide

61. Leaf blades ± strigose; phyllary midvein raised, orange-resinous; ray corolla 7–10 mm; CCo, SnFrB, n SCoRO, SCo/WTR ..... var. franciscensis

61' Leaf blades ± glabrous (except ciliate hairs); phyllary midvein generally not raised or orange-resinous; ray corolla 10–15 mm; KR, NCoRO ..... var. mendocinus

59' Phyllaries 0.5–0.8 mm wide, margins generally thick to ± scarious, ± glandless to prominently glandular

62. Phyllaries prominently glandular, also with appressed to ± ascending, acute-tipped hairs; wc SCoRO ..... E. conditii

62' Phyllaries ± glandless, glabrous to strigose or densely spreading-hairy

63. Leaves 2–4(5) cm, oriented variously; inner phyllaries 3.2–4.5 mm ..... E. foliosus var. foliosus

63' Leaves (2.5)4–6(8) cm, often ± oriented to 1 side of stem; inner phyllaries (4)5–6 mm

64. Stem 30–85 cm;  leaf tufts 0; leaves 35–80 mm, 1–2(4) mm wide; inner phyllaries not strongly scarious; ray flowers 26–50 ..... E. foliosus var. hartwegii

64' Stem 15–28 cm; axillary leaf tufts generally present; leaves 25–45 mm, (2)5–8 mm wide; inner phyllary margins strongly scarious; ray flowers 18–22 ..... E. mariposanus

48' Phyllaries generally ± equal; leaves entire to lobed, sometimes clasping, basal sometimes present, cauline often strongly reduced distally on stem, if present

65. Plant fibrous-rooted, generally from obvious rhizome or ± decumbent caudex; cauline leaves often ± clasping;

66. Glandless phyllary hairs with black cross-walls (sometimes only on basal cells of hairs)

67' Rays blue to purple ..... E. sanctarum (2)

66' Glandless phyllary hairs 0 or with clear cross-walls

68' Ray flowers 20–165 (80–300+ in E. glaucus)

69. Leaves thick, ± fleshy, entire or toothed; coastal ..... E. glaucus

69' Leaves ± thin, entire; coastal or inland

70. Glandless phyllary hairs prominent, glandular hairs sometimes present

71. Stem from thin, often stolon-like caudex branches with few fibrous roots ..... E. sanctarum (2)

71' Stem from short, thick, strongly fibrous-rooted rhizome or caudex

72. Stem 2–20(30) cm, hairs spreading; phyllaries ± black-purple; pappus bristles 12–16(20) ..... E. algidus (2)

72' Stem 30–100 cm, hairs appressed; phyllaries ± green; pappus bristles 20–30 ..... E. aliceae (2)

70' Glandless phyllary hairs 0, glandular hairs dense

73. Stem glabrous or sparsely minutely glandular; ray flowers 20–30(45) ..... E. cervinus

73' Stem ± appressed-hairy, sometimes also ± bristly; ray flowers 30–105

74. Fruit 2(4)-ribbed, moderately to densely strigose; proximal leaves generally coarsely , sometimes entire ..... E. aliceae (2)

74' Fruit 4–7-ribbed, sparsely strigose; proximal leaves entire ..... E. glacialis

75. Peduncles densely minutely strigose with loosely appressed, slightly crinkled hairs ..... var. glacialis

75' Peduncles bristly or ± stiffly long-soft-hairy ..... var. hirsutus

65' Plant taprooted or with taprooted caudex; cauline leaves not at all clasping

76. Stem spreading- or reflexed-hairy

77. Leaf clearly petioled,  oblanceolate, elliptic, obovate to spoon-shaped

78. Basal leaves 5–25 mm; cauline leaves 0; stem 1–4 cm; ray flowers 15–40, ray 4–6 mm ..... E. uncialis var. uncialis

78' Basal leaves 20–70 mm; cauline leaves gradually or much reduced; stem 1.5–30 cm; ray flowers (30)50–150, ray 5–13 mm

79. Head 1; involucre 5–8 mm; cauline leaves strigose to ± bristly, sometimes sparsely glandular; pappus bristles 12–16(20); SNH, SNE (exc W&I) ..... E. algidus (2)

79' Heads 1–several in open, ± flat-topped clusters; involucre 3–4 mm; cauline leaves densely, evenly ; pappus bristles 6–9(12), outer series of short bristles or narrow scales; e NCoRI, CaRF, n SNF, ScV (Sutter Buttes), W&I ..... E. incomptus (2)

77' Petiole indistinct, blade linear or oblanceolate, gradually  to base

80. Margins of proximal leaves generally hairy but not stiffly spreading-ciliate; generally > 2200 m

81. Basal leaves 20–80 mm; stem sparsely minutely glandular at least distally, and moderately hairy with short, stiffly spreading to reflexed, glandless hairs; phyllaries green; ray flowers 25–55, ray 6–11 mm ..... E. clokeyi var. pinzliae

81' Basal leaves 6–35 mm; stem densely minutely glandular, also with short-stiff and ± spreading glandless hairs; phyllaries ± black-purple; ray flowers 20–37, ray 4–7(10) mm ..... E. pygmaeus

80' Margins of proximal leaves generally stiffly long-spreading-ciliate; 1200–1800 m

82. Disk corolla (±) glabrous; pappus bristles 12–22; outer pappus of inconspicuous bristles or narrow scales; rays (40)55–115, 8–12 mm ..... E. pumilus var. intermedius

82' Disk corolla sharply scabrous; pappus bristles 5–15; outer pappus of prominent wide scales; rays 40–60, 7–9 mm ..... E. concinnus var. concinnus

76' Stem glabrous or ascending- to appressed-hairy (to ± spreading-hairy in Erigeron lassenianus)

83. Ray flowers 75–125; disk corolla throat ± widened ..... E. multiceps

83' Ray flowers generally 14–80; disk corolla ± narrowly 

84. Basal leaves 0 at flower

85. Leaves sharply reduced distally on stem; axillary leaf tufts 0; ray flowers 12–27(45) ..... E. oxyphyllus

85' Only most distal cauline leaves reduced; leaf tufts in axils; ray flowers 45–80 ..... E. karvinskianus

84' Basal leaves generally persistent

86. Basal leaves thread-like to linear

87. Stem 2–8 cm, leafless; stem hairs straight, appressed; basal leaves 5–25 mm; fruit ribs densely ciliate, faces glabrous ..... E. compactus

87' Stem 15–30 cm, generally leafy, at least proximally; stem hairs curved up, ± loose; basal leaves generally 20–70 mm; fruit ribs and faces sparsely hairy ..... E. filifolius

86' Basal leaves narrowly oblanceolate to elliptic or spoon-shaped (or linear in Erigeron lassenianus var. lassenianus and Erigeron robustior)

88. Plants ; caudex stout, branched; basal leaves oblanceolate to elliptic, petioled; cauline leaves abruptly reduced ..... E. tener

88' Plants not cespitose, caudex generally slender; basal leaves linear to narrowly oblanceolate,  indistinct; cauline leaves gradually reduced

89. Basal leaves generally persistent; cauline leaves generally smaller than basal; heads 1–4(7) ..... E. eatonii

90. Involucre (14)17–23 mm diam; longest phyllaries 7–11 mm; disk corolla 4.4–6.8 mm ..... var. nevadincola

90' Involucre 8–16 mm diam; longest phyllaries 5–8 mm; disk corolla 3–5 mm

91. Stem 10–23 cm; disk corolla 3–4 mm; pappus bristles 16–20, 3–3.5 mm ..... var. plantagineus

91' Stem 4–12(21) cm; disk corolla 3.5–5 mm; pappus bristles 18–30, 3.5–5 mm ..... var. sonnei

89' Basal leaves persistent at, or withering before, flower; cauline leaves gradually or little reduced; heads (1)2–7(18)

92. Phyllaries densely minutely glandular; involucre 4–5.5 mm, 6–10(12) mm wide; leaves generally 1-veined ..... E. lassenianus var. lassenianus

92' Phyllaries generally glandless; involucre generally 6–8.5 mm, (9)12–20 mm wide; leaves generally 3-veined

93. Plants 10–22(27) cm; taproots ± thick, (3)5–8 mm wide; basal leaves oblanceolate to ± narrowly spoon-shaped; cauline leaves ± continuing to heads; involucres (5)6–7 mm, 9–12(14) mm wide; phyllaries elliptic-oblanceolate to oblong-oblanceolate, abruptly  ..... E. maniopotamicus

93' Plants (15)25–55 cm; taproots ± thin, 2–3 mm wide; basal leaves linear to very narrowly oblanceolate; cauline leaves ending ± well below heads; involucres 6–8.5 mm, (12)14–20 mm wide; phyllaries narrowly oblanceolate to , acute-acuminate ..... E. robustior

 

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