The Jepson Manual: Higher Plants of California

    THIS PAGE IS NO LONGER UPDATED
    AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY
  • Up-to-date information about California vascular plants is available from the Jepson eFlora.

Names are linked to treatments from the Manual


Key to SENECIO

N.B.: couplets are linked, e.g., 1. is linked to 1'.

  1. Ligules generally pink to purple or blue (rarely white) — aliens of coast
 
    2. Herbage sticky; main leaves deeply toothed or lobed
S. elegans
    2' Herbage not sticky; main leaves merely toothed
S. hybridus
  1' Ligules generally yellow (to brick-colored, rarely 0 or white)
 
    3. Vine; leaves ivy-like; weedy
S. mikanioides
    3' Plants ± erect
 
      4. Subshrub or shrub (if weakly woody, branching aspect shrub-like); leaves or segments linear
 
        5. Outermost phyllaries well developed, some 1/2 × main phyllaries
S. flaccidus
          6. Herbage ± gray-tomentose
var. douglasii
          6' Herbage ± glabrous
var. monoensis
        5' Outermost phyllaries 0 or inconspicuous — herbage ± glabrous (except sometimes leaf lower surface or heads)
 
          7. Leaves pinnately lobed, ± hairy below — Channel Islands
S. lyonii
          7' Leaves generally linear, ± entire
 
            8. Phyllaries ± 13; leaves ± thread-like, < 2 mm wide; coastal
S. blochmaniae
            8' Phyllaries ± 8; some leaves > 2 mm wide; e of High Sierra Nevada
S. spartioides
      4' Annual or perennial herb; leaves or segments wider than linear
 
        9. Leaves ± equal, evenly distributed or crowded upward at flowering
 
          10. Leaves generally 1–2-pinnately lobed; heads 20–60; stems 1–few, erect
S. jacobaea
          10' Leaves entire to lobed (if 2-pinnately lobed, heads < 20, stems ascending)
 
            11. Annual from slender taproot
 
              12. Ligules conspicuous, spreading
S. californicus
              12' Ligules 0 or small, often recurved or inrolled
 
                13. Main leaves cordate-clasping, bases 1–2 cm wide; herbage glabrous
S. mohavensis
                13' Leaves petioled, little or not clasping; herbage glabrous or tomentose
 
                  14. Outermost phyllaries conspicuous, black-tipped; main phyllaries ± 21; herbage ± glabrous — abundant weed
S. vulgaris
                  14' Outermost phyllaries 0 or inconspicuous, green-tipped; herbage glabrous to tomentose
 
                    15. Main phyllaries generally ± 8, sometimes 13; plants generally < 2 dm; herbage generally glabrous; native
S. aphanactis
                    15' Main phyllaries ± 13 or 21; plants generally 3–8 dm; herbage sparsely rough-tomentose; naturalized weed
S. sylvaticus
            11' Perennial from taproot, caudex, or rhizome
 
              16. Plants generally < 2 dm, often spreading; alpine or subalpine
 
                17. Leaves widely linear; plants rhizomed
S. pattersonensis
                17' Leaves ± ovate; plants taprooted
S. fremontii
                  18. Phyllaries (6)8–10 mm; upper leaves well developed; High Cascade Range, Warner Mountains
var. fremontii
                  18' Phyllaries 5–7(8) mm; upper leaves bract-like; Sierra Nevada, San Bernardino Mountains, East of Sierra Nevada
var. occidentalis
              16' Plants 5+ dm, erect; montane
 
                19. Leaves pinnately lobed or dissected; herbage tomentose with jointed hairs or becoming ± glabrous
S. clarkianus
                19' Leaves dentate; herbage glabrous or sparsely tomentose below
 
                  20. Leaves ± linear-lanceolate, tapered
S. serra var. serra
                  20' Leaves narrowly triangular, truncate or hastate
S. triangularis
        9' Leaves reduced upward; lower leaves prominent, generally persistent
 
          21. Plant from button-like caudex; roots many, fleshy-fibrous, unbranched
 
            22. Plants glabrous or minutely hairy among heads
 
              23. Herbage glaucous; leaves fleshy; plants sometimes 10–20 dm, tolerant of standing saltwater
S. hydrophilus
              23' Herbage not glaucous; leaves firm; plants < 10 dm, of damp soil but not standing water
S. hydrophiloides
            22' Plants hairy, sometimes becoming subglabrous
 
              24. Ray flowers 0(–2); disk flowers < 20; main phyllaries generally ± 8, sometimes 13; basal leaf margins wavy or shallow-toothed
S. aronicoides
              24' Ray flowers generally present; disk flowers 20–50; main phyllaries generally ± 21, sometimes 13; basal leaves generally subentire
S. integerrimus
                25. Ligules off-white to cream-colored
var. ochroleucus
                25' Ligules yellow, rarely 0
 
                  26. Main phyllaries 5–10 mm, lanceolate, often strongly black-tipped; ± hairy
var. exaltatus
                  26' Main phyllaries 8–12 mm, ± linear, ± not black-tipped; densely hairy
var. major
          21' Plants from taproot, rhizome, or non-button-like caudex
 
            27. Stems from thick, creeping or erect rhizome; roots fleshy, unbranched; leaves tapered to winged petiole, marginal teeth hard, translucent
 
              28. Ray flowers 0; main phyllaries ± 21; disk corollas orange-yellow
S. astephanus
              28' Ray flowers present; main phyllaries ± 13; disk corollas yellow
S. scorzonella
            27' Stems from thin taproot, caudex, or rhizome; roots fibrous, branched; leaves subentire to pinnately divided, marginal teeth not hard, not translucent
 
              29. Herbage (sub)glabrous; basal leaves entire to toothed
 
                30. Ray flowers 0 (or inflorescence distinctly umbel-like)
 
                  31. Heads 8–20+; corollas yellow; leaves thin
S. indecorus
                  31' Heads generally < 6; corollas deep yellow to brick-colored; leaves thick
S. pauciflorus
                30' Ray flowers present (or inflorescence cyme-like)
 
                  32. Head 1(–3) — plant from slender rhizome
S. cymbalarioides
                  32' Heads generally 4–many
 
                    33. Plants sparsely short-hairy at maturity
S. layneae
                    33' Plants ± completely glabrous at maturity
 
                      34. Lower leaf bases cordate to truncate
 
                        35. Corollas orange-yellow to orange; basal leaves ± long as wide, rounded at tip
S. ganderi
                        35' Corollas yellow; basal leaves widely lanceolate, blunt or pointed at tip
S. pseudaureus var. pseudaureus
                      34' Lower leaf bases obtuse to tapered
 
                        36. Herbage glaucous; leaves ± entire; plants < 10 dm
S. clevelandii
                        36' Herbage not glaucous; leaves subentire to toothed; plants generally < 4 dm
S. streptanthifolius
              29' Young herbage hairy (sometimes becoming subglabrous) or basal leaves pinnately lobed or divided
 
                37. Basal leaves pinnately divided or lobed; herbage ± glabrous
 
                  38. Terminal lobe of lower leaves = or > lateral; lateral lobes 1–3 pairs
S. bolanderi var. bolanderi
                  38' Terminal lobe of lower leaves < lateral (or lateral lobes > 6 pairs)
 
                    39. Heads small, main phyllaries generally 4–8 mm
S. multilobatus
                    39' Heads large, main phyllaries generally 8–10 mm
 
                      40. Plants 4–10 dm; stems generally 1 from a short caudex; mid-cauline leaves ± prominent
S. breweri
                      40' Plants 2–5(7) dm; stems often several from branched caudex; mid-cauline leaves reduced
S. eurycephalus
                        41. Leaves irregularly lobed or dissected, lobes toothed; stems several but aspect not shrub-like
var. eurycephalus
                        41' Leaves deeply and finely 1–2-dissected; aspect ± shrub-like
var. lewisrosei
                37' Basal leaves entire to dentate (or if pinnate, loosely tomentose)
 
                  42. Heads generally > 6
 
                    43. Herbage permanently ± hairy; leaf margins flat; blade length 1.5–2 × width
S. canus
                    43' Herbage ± glabrous at flowering; leaf margins often weakly rolled under; blade length > 2 × width
S. macounii
                  42' Heads 1–few (generally < 6)
 
                    44. Leaves lobed
S. ionophyllus
                    44' Leaves subentire or dentate
 
                      45. Disk 18+ mm diam, ligules orange to brick-colored
S. greenei
                      45' Disk < 15 mm diam, ligules yellow
 
                        46. Cauline leaves gradually reduced, conspicuous
S. bernardinus
                        46' Cauline leaves bract-like (plants ± scapose)
S. werneriifolius


University & Jepson Herbaria Home Page |

Copyright by the Regents of the University of California