OSMORHIZA
1. Fruits glabrous, obtuse at base; flowers yellow; stems clustered O. occidentalis
1. Fruits bristly, long-tapering at base; flowers whitish, sometimes pink or purple; stems usually solitary.
2. Fruits convexly narrowed to the rounded or obtuse summit, the apex not beaklike O. depauperata
2. Fruits concavely narrowed to the summit, the terminal portion a beaklike apex.
3. Fruits usually 12-22 mm long, the beaklike apex as tall as wide; leaves hairy O. berteroi
3. Fruits usually 8-13 mm long, the beaklike apex wider than tall; leaves glabrous O. purpurea
SANICULA
1. Plants with fibrous roots from a short, simple stem-base; flowers greenish-white S. marilandica
1. Plants with taproots; flowers yellow to purple.
2. Plants prostrate or ascending; involucels surpassing the heads S. arctopoides
2. Plants erect; involucels inconspicuous.
3. Principal leaves once or twice pinnatifid, with a distinctly toothed leaf axis, primary divisions 7 or more; flowers purple S. bipinnatifida
3. Principal leaves palmately or pinnipalmately lobed or pinnately divided in 3’s, without a toothed leaf axis, primary divisions 3-5; flowers yellow.
4. Leaves palmately or pinnipalmately lobed or divided, without a narrow leaf axis, the primary divisions merely lobed or saw-toothed S. crassicaulis
4. Leaves more or less pinnately divided in 3’s, the primary divisions tending to be pinnatifid, the lowest pair of primary divisions separated from the terminal segment or segments by a narrow, entire leaf axis S.graveolens

TORILIS

1. Fruits 3-4 mm long with more or less straight spines minutely hooked at the tips T. arvensis
1. Fruits 2-2.5 mm long with curved spines not hooked at the tips T. japonica
APOCYNACEAE
1. Flowers greenish-white to pink, 2-10 mm long; seeds with long tufts of cottony hairs Apocynum
1. Flowers blue, rarely white, 3-5 cm long; seeds without long tufts of cottony hairs Vinca
APOCYNUM
1. Corollas greenish-white to white, 2-4.5 mm long, usually less than twice as long as the calyces; leaves ascending A. cannabinum
1. Corollas pinkish, 3.5-10 mm long, usually more than twice as long as the calyces; leaves spreading to drooping.
2. Calyces usually at least half as long as the corollas, lobes abruptly sharp-pointed to long-pointed
x A. floribundum
2. Calyces usually less than half as long as the corollas, lobes obtuse A. androsaemifolium
VINCA
1. Flowers usually 20-30 mm wide, usually solitary; calyx lobes glabrous; leaves narrowed at the base
V. minor
1. Flowers usually 30-50 mm wide, up to 4 per stem; calyx lobes ciliate; leaves squared-off or somewhat heart-shaped at the base V. major
ARALIACEAE
1. Leaves compound Aralia
1. Leaves simple.
2. Stems erect; leaves deciduous and spiny Oplopanax
2. Stems climbing by aerial roots; leaves evergreen and glabrous Hedera
ASCLEPIADACEAE
ASCLEPIAS
1. Leaves egg-shaped or lanceolate, tapered at the base; pods lacking tubercles A. ovalifolia
1. Leaves oblong or oval, rounded or heart-shaped at the base; pods with soft tubercles A. speciosa

ASTERACEAE

1. Flowers all strap-shaped and perfect; juice milky (Lactuceae [Cichorieae]) Group I
1. Flowers not all strap-shaped, the strap-shaped (ray) flowers marginal if present, either pistillate or neutral; juice usually watery.
2. Heads with ray and disk flowers.
3. Ray flowers white, pink, purple, red or blue, never yellow or orange Group II
3. Ray flowers yellow or orange (sometimes purplish, dark brown or reddish-brown at the base).
4. Pappus papery or of firm awns (or sometimes lacking); receptacles papery, bristly or naked Group III
4. Pappus partly or wholly of hairlike (sometimes feathery) bristles; receptacles naked Group IV
2. Heads discoid or disciform (without ray flowers).
5. Pappus partly or wholly of numerous hairlike (sometimes feathery) bristles Group V
5. Pappus of scales, awns or very short papery bristles, or a mere crown (or sometimes lacking) Group VI
Group I (Flowers all strap-shaped and perfect; juice milky)
1. Achenes without a pappus Lapsana
1. Achenes with a pappus.
2. Pappus double, an inner row of numerous, fragile hairlike bristles subtended by a row of short scales Krigia
2. Pappus a single series of bristles or scales.
3. Pappus of simple (sometimes finely-barbed) hairlike bristles.
4. Stem leaves well-developed, broad, usually well over 1 cm wide.
5. Leaves simple, entire to shallowly toothed; achenes cylindric Prenanthes
5. Leaves, or at least some of them, pinnatifid; achenes more or less strongly flattened.
6. Achenes beaked (or beakless in Lactuca biennis), somewhat enlarged near summit where pappus attached; leaves not auriculate Lactuca
6. Achenes beakless, not enlarged near summit; leaves auriculate Sonchus
4. Stem leaves narrow, usually less than 1 cm wide, reduced upwards, sometimes merely scales or plants with basal leaves only.
7. Achenes spinulose or prickly Taraxacum
7. Achenes smooth or nearly so.
8. Ray flowers pink (rarely white); stem leaves reduced to mere scales Lygodesmia
8. Ray flowers bright yellow to orange, red or pink (in Agoseris lackschewitzii); plants with basal leaves only or with at least a few stem leaves.
9. Plants with basal leaves only or nearly so; heads solitary.
10. Achenes beaked Agoseris
10. Achenes beakless.
11a. Plants stoloniferous; achenes 1.5-2 mm long Hieracium (pilosella)
11a. Plants not stoloniferous; achenes 4-12 mm long.
11b. Outer involucral bracts less than 1/2 the length of the inner ones Microseris (borealis)
11b. Outer involucral bracts more than 1/2 the length of the inner ones Agoseris (glauca)
9. Plants with true stems, with at least a few stem leaves; heads few to numerous.
12. Achenes not tapered at both ends, beakless Hieracium
12. Achenes tapered at both ends, beaked.
13. Achene tips with a ring of small scales at base of slender beak Chondrilla
13. Achene tips without ring of scales, beaked or beakless Crepis
3. Pappus of feathery bristles, bristlelike scales, scales and bristles, or minute scales.
14. Pappus of minute scales; rays blue (rarely white) Cichorium
14. Pappus well-developed; rays pink, yellow, orange or purple (occasionally white).
15. Ray flowers pink (occasionally white); leaves small, mainly on stems, often scalelike Stephanomeria
15. Ray flowers yellow, orange or purple; leaves well-developed.
16. Pappus of scales and bristles or bristlelike scales.
17. Pappus of long, narrow, tapering bristlelike scales; leaves usually crisped or wavy Nothocalais
17. Pappus of scales and bristles; leaves entire or with linear lobes.
18. Pappus of 5 short scales alternating with as many bristles; achenes l.5-2 mm long Krigia
18. Pappus of 5 or 15-20 narrow scales, each bearing a long bristle; achenes 3.5-13 mm long Microseris
16. Pappus of feathery bristles.
19. Plume branches of the pappus interwebbed; plants with stem leaves, the leaves somewhat grasslike Tragopogon
19. Plume branches of the pappus not interwebbed; plants with or without stem leaves.
20. Receptacles papery-bracted; achenes with beaks as long or longer than the achenes Hypochaeris
20. Receptacles naked; achenes beakless or with beaks shorter than the achenes Leontodon

Group II (Heads with ray and disk flowers, ray flowers white, pink, purple, red or blue)
1. Receptacles papery or bristly throughout (or only towards the middle in Anthemis cotula); pappus of scales, awns or very short papery bristles, or a mere crown (or sometimes lacking).
2. Stem leaves regularly opposite, well-developed Galinsoga
2. Stem leaves all or nearly all alternate, or the plants with mostly basal leaves.
3. Marginal disk flowers enlarged into irregular, falsely subradiate corollas; true ray flowers lacking; receptacles densely bristly, the bristles not individually subtending the flowers Centaurea (cyanus)
3. Marginal disk flowers not enlarged conspicuously; ray flowers present; receptacles papery, the bracts individually subtending the flowers.
4. Ray flowers large, 1.5-4.5 cm long Ratibida
4. Ray flowers small, seldom over 1 cm long.
5. Ray flowers few, usually 3-5, short, less than 5 mm long; perennials Achillea
5. Ray flowers more numerous, usually 10-25, larger, mostly 5-10 mm long; annuals Anthemis
1. Receptacles naked, or with a row of papery scales between the ray and disk flowers; pappus various.
6. Pappus of the disk flowers composed partly or wholly of hairlike bristles.
7. Basal leaves arrowhead-shaped, heart-shaped or palmately lobed Petasites
7. Basal leaves not arrowhead-shaped, heart-shaped or palmately lobed.
8. Ray flowers numerous, filiform, short, scarcely longer than the disk flowers; involucres and styles approaching that of Erigeron; annuals Conyza
8. Ray flowers few to numerous, well-developed, conspicuous, obviously surpassing the disk (except for a few species which are either perennials or have the involucres and styles of Aster).
9. Involucral bracts subequal or more or less imbricate, often green in part but neither definitely leafy nor with a papery base and leafy green tips; style branches lanceolate or broader, abruptly sharp-pointed to obtuse, 0.5 mm long or less, or lacking.
10. Pistillate corollas numerous, filiform, with narrow, short, erect rays, these sometimes not exceeding the disk, or the inner pistillate corollas tubular and rayless; involucres glandular and/or stiff-hairy, but not woolly long-hairy Trimorpha
10. Pistillate corollas few to numerous, the rays well-developed and spreading, or occasionally reduced or rarely lacking, or if otherwise then the involucres woolly long-hairy Erigeron
9. Involucral bracts either subequal and the outer leafy or more commonly evidently imbricate, with papery base and evident green tip, sometimes papery throughout; style branches lanceolate or narrower, abruptly sharp-pointed to long-pointed, usually more than 0.5 mm long.
11. Plants distinctly taprooted; leaves spinulose-tipped and often spinulose-toothed Machaeranthera
11. Plants with fibrous roots or rhizomes; leaves not spinulose Aster
6. Pappus of scales, awns, distinctly flattened papery bristles or a mere crown (or sometimes lacking).
12. Receptacles evidently conic or hemispheric.
13. Plants with basal leaves only; pappus lacking Bellis
13. Plants leafy-stemmed; pappus a minute crown or border Matricaria
12. Receptacles flat or nearly so.
14. Pappus a short crown, or lacking Leucanthemum
14. Pappus of the disk flowers of about 10 or more flattened, bristlelike scales Townsendia
Group III (Heads with ray and disk flowers; ray flowers yellow or orange;
pappus papery or of firm awns, or lacking)
1. Receptacles papery or bristly throughout.
2. Involucral bracts in two distinct, dissimilar series; achenes subterete or strongly flattened at right angles to the radius of the head H
3. Plants aquatic; leaves filiform-dissected; achenes subterete Megalodonta
3. Plants subaquatic or terrestrial; leaves not filiform-dissected; achenes strongly flattened at right angles to the radius of the head H
4. Pappus of 2-6 firm, mostly retrorsely barbed awns Bidens
4. Pappus of 2 minute teeth, or lacking Coreopsis
2. Involucral bracts in one or more similar series; achenes either not much flattened, or if so, then flattened parallel to the radius of the head H
5. Receptacles merely bristly Gaillardia
5. Receptacles papery with definite bracts, not bristly.
6. Plants with basal leaves only or nearly so, the stem leaves, if any, much reduced Balsamorhiza
6. Plants with stem leaves.
7. Stem leaves alternate.
8. Receptacles columnar; rays yellow; achenes flattened Ratibida
8. Receptacles hemispheric; rays orange, orange-yellow or yellow; achenes equably quadrangular Rudbeckia
7. Stem leaves opposite, at least below.
9. Pappus persistent; disk achenes strongly flattened, thin edged; involucral bracts densely fringed Helianthella
9. Pappus readily deciduous (at least as to the two principal awn scales); achenes only slightly or moderately flattened; involucral bracts not densely fringed Helianthus
1. Receptacles naked, or with a single row of papery scales between the ray and disk flowers.
10. Ray flowers well-developed and conspicuous, mostly 5-30 mm long; receptacles naked.
11. Pappus of firm, deciduous awns; involucres more or less strongly sticky-resinous Grindelia
11. Pappus of papery or transparent scales, or a mere crown, or lacking; involucres not resinous although sometimes glandular-hairy.
12. Leaves mostly pinnatifid; ray flowers ascending, minutely notched at the apex; receptacles low conic Eriophyllum
12. Leaves simple, toothed; ray flowers soon reflexed, prominently 3-lobed; receptacles hemispheric to rounded Helenium
10. Ray flowers short and inconspicuous, mostly 1-5 mm long or, if longer (in some Madia), then receptacle with a row of bracts between the ray and disk flowers.
13. Leaves bipinnatifid to pinnately dissected Tanacetum
13. Leaves entire to toothed.
14. Involucres spindle-shaped, egg-shaped or urn-shaped, enfolding the ray flowers, more or less glandular Madia
14. Involucres only slightly convex, not enfolding the ray flowers, not glandular.
15. Involucral bracts well graduated in several series; pappus lacking Jaumea
15. Involucral bracts in a single series; pappus of 3-5 awns and about as many alternating, tattered, shorter scales Lasthenia
Group IV (Heads with ray and disk flowers; ray flowers yellow or orange;
pappus partly or wholly of numerous [sometimes feathery] bristles)
1. Leaves, except some of the reduced uppermost ones, opposite Arnica
1. Leaves alternate, or all basal.
2. Receptacles strongly conic; annuals Crocidium
2. Receptacles flat or nearly so; perennials.
3. Heads large, involucres 2-2.5 cm high; disks 3-5 cm wide; larger leaves densely velvety below; plants taprooted, weeds, up to 2 m tall Inula
3. Heads smaller, if larger, then characters otherwise than those above.
4. Involucral bracts in a single series, equal, narrow, commonly with a few much shorter outer ones at the base Senecio (also Sinosenecio 12)
4. Involucral bracts in 2 or more series, equal or imbricate, narrow to broad.
5. Pappus double, bristles of the outer series inconspicuous, distinctly shorter than the inner.
6. Heads solitary; leaves linear or mainly basal Erigeron (aureus and linearis)
6. Heads several, leaves oblong to oblong spoon-shaped, mainly stem leaves Heterotheca
5. Pappus single, bristles sometimes unequal but not distinctly divided into an inner and outer series.
7. Heads solitary or if several then plants taprooted
8. Ray flowers inconspicuous; plants of the steppe or lower montane zones Pyrrocoma
8. Ray flowers conspicuous; plants of the subalpine or alpine zones Tonestus
7. Heads usually several to many.
9. Plants shrubby Ericameria
9. Plants herbaceous.
10. Lower leaves deeply heart-shaped Doronicum
10. Lower leaves not heart-shaped.
11. Leaves pitted (sometimes obscurely so); heads mostly unstalked in small clusters, rays mostly 15-30 Euthamia
11. Leaves not pitted; heads not clustered; rays 7-13, rarely 17 Solidago
Group V (Heads discoid or disciform; pappus partly or wholly
of numerous hairlike [sometimes feathery] bristles)
1. Leaves more or less spiny and thistlelike and/or the receptacles densely bristly.
2. Leaves more or less spiny and thistlelike.
3. Outer and middle involucral bracts leaflike with spreading, rigidly-spiny blades, these similar to the upper leaves Carthamus
3. Outer and middle involucral bracts not at all leaflike.
4. Pappus bristles feathery Cirsium
4. Pappus bristles merely finely-barbed or smooth.
5. Pappus bristles smooth; stems smooth Silybum
5. Pappus bristles finely-barbed; stems with conspicuous spiny-margined wings.
6. Receptacles honeycombed; stems densely woolly Onopordum
6. Receptacles not honeycombed; stems nearly glabrous Carduus
2. Leaves entire to toothed, not at all bristly or spiny, the plants not thistlelike.
7. Involucres with some bracts stiff-fringed, raggedly torn, spiny or irregulary wavy Centaurea
7. Involucres with all bracts entire.
8. Lower leaves linear to oblanceolate, often lobed or divided; plants of the steppe and montane zones Acroptilon
8. Lower leaves lanceolate to triangle-egg-shaped, saw-toothed; plants of the subalpine or alpine zones Saussurea
1. Leaves not spiny; receptacles naked, or nearly so.
9. Shrubs.
10. Involucral bracts 4-6, equal Tetradymia
10. Involucral bracts more numerous, graduated or at least in several series.
11. Involucral bracts aligned in more or less vertical ranks Chrysothamnus
11. Involucral bracts not aligned in vertical ranks Brickellia
9. Herbs (subshrubby in Luina hypoleuca).
12. Flowers all perfect and fertile (heads discoid).
13. Leaves opposite; flowers yellow or orange Arnica
13. Leaves alternate, or if rarely opposite or whorled, then the flowers not yellow or orange.
14. Involucral bracts in one series, equal, sometimes with a few short outer ones at the base.
15. Leaves toothed and some of them more or less pinnatifid, never palmately cleft Senecio (indecorus and pauciflorus)
15. Leaves simple and entire or palmately cleft.
16. Leaves simple and entire Luina
16. Leaves palmately cleft Cacaliopsis
14. Involucral bracts more or less graduated in 2-several series.
17. Pappus bristles feathery Saussurea
17. Pappus bristles merely finely-barbed or smooth.
18. Leaves in whorls of three or four Eupatorium
18. Leaves mostly alternate.
19. Leaves mostly stem; involucres taller than wide Brickellia
19. Leaves mostly basal; involucres wider than tall Pyrrocoma
12. Flowers all, or at least the outer ones, female (heads disciform).
20. Basal leaves heart-shaped Petasites
20. Basal leaves, if any, not heart-shaped.
21. Plants more or less white-woolly; involucral bracts mostly with dry, papery, thin, white to yellowish, brownish, or blackish green tips.
22. Receptacles papery, at least near the margin, and simulating an involucre Filago
22. Receptacles naked.
23. Plants taprooted annuals or perennials; heads all with outer female and central (or functionally male ) perfect flowers Gnaphalium
23. Plants fibrous-rooted perennials, often with rhizomes or stolons; the heads on at least some of the plants with only male or female flowers.
24. Basal leaves usually conspicuous, tufted, and persistent, the stem ones mostly reduced upwards and often few or lacking Antennaria
24. Basal leaves soon deciduous, scarcely if at all larger than the numerous stem ones Anaphalis
21. Plants often hairy but not white-woolly; involucral bracts not markedly papery at the tip.
25. Perennials Trimorpha (acris)
25. Annuals Aster (brachyactis)
Group VI (Heads discoid or disciform; pappus of scales, awns or very short
papery bristles, or a mere crown, or sometimes lacking)
1. Involucres, or at least some of them, either armed with short, hooked prickles, or nutlike or burlike and provided with tubercles and spines.
2. Heads of two types; involucres of the female heads nutlike or burlike and provided with hooked prickles, tubercles and spines, those of the male heads unarmed; receptacles papery; corollas small and inconspicuous, or lacking.
3. Female involucres with hooked prickles Xanthium
3. Female involucres with tubercles or straight spines Ambrosia
2. Heads all alike with numerous perfect flowers; involucral bracts hooked at the tip; receptacles bristly; corollas more or less evident Arctium
1. Involucres neither nutlike or burlike nor provided with hooked prickles, all alike, spiny only in Centaurea.
4. Receptacles papery or bristly throughout, or a few of the central flowers bractless.
5. Plants more or less white-woolly; flowers inconspicuous Psilocarphus
5. Plants either not white-woolly or flowers conspicuous, or both.
6. Heads small, involucres 1.5-4 mm tall; the disks up to about 5 mm wide Iva
6. Heads obviously larger, involucres over 6 mm tall; the disks usually over 1 cm wide.
7. Receptacles papery; involucral bracts in two series and obviously of two types Bidens
7. Receptacles bristly; involucral bracts not in two series.
8. Involucres with some bracts stiff-fringed, ragged, spiny or irregularly wavy margined Centaurea
8. Involucres with all bracts entire Acroptilon
4. Receptacles naked or with a single row of papery bracts between the ray and disk flowers.
9. Achenes prominently spine-tipped Soliva 13
9. Achenes not spine-tipped.
10. Lowermost leaves deltoid-egg-shaped to more or less kidney-shaped below, white-woolly beneath; involucral bracts few, usually only 4-5 Adenocaulon
10. Lowermost leaves not deltoid-egg-shaped to more or less kidney-shaped; involucre bracts usually more numerous.
11. Leaves regularly opposite.
12. Involucral bracts well graduated in several series; pappus lacking Jaumea
12. Involucral bracts in a single series; pappus of 3-5 awns and about as many alternating, tattered, shorter scales Lasthenia
11. Leaves alternate, or occasionally some of the lower ones opposite.
13. Pappus of short, distinct awns or scales Chaenactis
13. Pappus a mere minute crown or lacking.
14. Involucral bracts in a single series, equal, each subtending and wholly enclosing an achene, or nearly so Madia
14. Involucral bracts in several series, not enclosing the achenes.
15. Heads in an elongate inflorescence, relatively small, usually numerous Artemisia
15. Heads in an open, round- or flat-topped inflorescence, small to large, solitary to few, sometimes numerous.
16. Receptacles conspicuously hemispheric or conical Matricaria
16. Receptacles flat or somewhat convex.
17. Leaves fernlike (pinnate or bipinnate) throughout; achenes sparsely glandular; pappus a minute toothed crown Tanacetum (vulgare)
17. Leaves toothed or lobed below, becoming entire above, somewhat succulent and sheathing at the base; achenes not glandular; pappus lacking Cotula

ACHILLEA
1. Leaves pinnately dissected, the divisions again dissected: plants widespread in BC A. millefolium
1. Leaves incised, the divisions of the latter merely toothed; plants of northeastern BC A. sibirica

1. Leaves grey, long-hairy to woolly; plants usually in and east of the Coast-Cascade Mountains.
2. Involucral bract margins light brown to black; stems usually less than 30 cm tall; plants of the subalpine and alpine zones var. alpicola (Rydb.) Garrett
2. Involucral bract margins light brown to straw-coloured; stems usually more than 30 cm tall; plants of the montane and steppe zones var. lanulosa (Nutt.) Piper in Piper & Beattie
1. Leaves usually green, moderately long-hairy; plants of coastal regions.
3. Involucral bract margins dark brown to black; stems 10-40 cm tall var. borealis (Bong.) Farwell
3. Involucral bract margins hyaline to light straw-coloured; stems 30-100 cm tall var. pacifica (Rydb.) G.N. Jones

AGOSERIS
1. Ray flowers pink (drying purplish) A. lackschewitzii
1. Ray flowers burnt orange or yellow (often drying pinkish).
2. Achenes often beakless, if beaked then the beak stout and up to about half as long as the body A. glauca
2. Achenes always beaked, the beak slender and more than half as long as the body.
3. Beak up to 2 times as long as the body; rays usually burnt orange, rarely yellow A. aurantiaca
3. Beak 2-4 times as long as the body; rays always yellow.
4. Plants annual; involucres with conspicuous purple crosswalls on multicellular hairs A. heterophylla
4. Plants perennial; involucres without purple crosswalls on the multicellular hairs
A. grandiflora

AMBROSIA
1. Involucres with 2-4 series of short, sharp spines; leaves mostly alternate A. chamissonis
1. Involucres with a single series of short spines or tubercles above the middle; leaves, or at least the lower ones, opposite.
2. Plants annual from fibrous roots; leaves mostly stalked, mostly twice pinnatifid; involucres with short spines A. artemisiifolia
2. Plants perennial from creeping roots; leaves short-stalked or nearly unstalked, only once pinnatifid; involucres with tubercles A. psilostachya

ANTENNARIA

1. Heads solitary on the stems, rarely 2-3, terminal.
2. Leaves glabrous or glabrate and greenish above; heads on sparsely leafy stems; plants of northern BC A. monocephala
2. Leaves densely woolly above and below; heads on leafy stems; plants of extreme south-central BC.
3. Plants with conspicuous slender, leafless stolons A. flagellaris
3. Plants without stolons A. dimorpha
1. Heads 2-many on the stems, rarely solitary.
4. Basal leaves distinctly less hairy and greener above than below, often sooner or later glabrate.
5. Heads usually borne in an open elongate inflorescence; stigmas equalling or surpassing the pappus; basal leaves with 3-7 prominent veins A. racemosa
5. Heads borne in a crowded or sometimes headlike inflorescence; plants chiefly apomictic; pappus surpassing the stigmas; basal leaves with 1-3 prominent veins.
6. Leaves glabrous above from the beginning A. howellii
6. Leaves thinly woolly-hairy above when young, sometimes glabrous with age A. neglecta
4. Basal leaves nearly as densely hairy above as below, glabrate only in extreme age.
8. Plants mat-forming, with numerous stolons.
9. Stolons woody; terminal papery portion of the middle and outer involucral bracts light brown, sometimes white or streaked with pink A. umbrinella
9. Stolons leafy; terminal papery portion of the involucral bracts darkish green, dark brown or blackish throughout, or white (and greenish at the base) or combinations of white, pink, rose or light brown.
10. Terminal papery portion of the involucral bracts dark green, dark brown or blackish throughout.
11. Middle and upper stem leaves with flat, linear, papery tips; populations containing only female plants A. alpina
11. Middle and upper stem leaves with blunt, tapered or sharp, slender tips, populations containing both male and female or only female plants A. media
10. Terminal papery portion of the involucral bracts white (and greenish at the base) or combinations of white, pink, rose or light brown.
12. Female involucres 7-11 mm tall; the dry female corollas 5-8 mm long A. parvifolia
12. Female involucres 4-8 mm tall; the dry female corollas 2.5-4.5 mm long.
13. Papery portion of the involucral bracts white to light yellow, greenish at the base; upper stems with glandular hairs A. microphylla
13. Papery portion of the involucral bracts combinations of white, green, pale yellow, pink, rose or light brown; upper stems without glandular hairs or if glandular hairs present then the involucral bracts pink to rose and the glands with reddish crosswalls A. rosea
8. Plants not mat-forming, without stolons, often multiple-stemmed from a branched rhizome or stem-base.
14. Involucral bracts papery to the base, glabrous or nearly so, the outermost bracts occasionally slightly woolly at the base A. luzuloides
14. Involucral bracts with a densely hairy, not at all papery lower portion, the pubescence extending even to the inner bracts.
15. Plants mostly 10-20 cm tall; involucres blackish in aspect, although the inner bracts may be white at the tip; plants of the subalpine to alpine zones in BC A. lanata
15. Plants mostly 20-50 cm tall; involucres whitish to blackish in aspect; plants of the steppe, montane and occasionally the subalpine zones of BC A. pulcherrima
ANTHEMIS
1. Rays yellow A. tinctoria
1. Rays white.
2. Receptacles papery throughout; achenes with smooth ribs A. arvensis
2. Receptacles papery only above the middle; achenes with glandular-tuberculate (bumpy) ribs A. cotula
ARCTIUM
1. Involucral bracts flat, straight and spreading; heads usually more than 2.5 cm wide, stalked A. lappa
1. Involucral bracts angled or narrowed, curved and generally ascending; heads usually less than 2.5 cm wide, short-stalked or unstalked A. minus

ARNICA

1. Stem leaves mostly 5-12 pairs.
2. Involucral bracts blunt or abruptly pointed, bearing a conspicuous tuft of long, white hairs at or near the tips A. chamissonis
2. Involucral bracts more or less sharply pointed, lacking a tuft of white hairs at the tips.
3. Leaves entire or nearly so A. longifolia
3. Leaves more or less toothed A. amplexicaulis
1. Stem leaves mostly 1-4 pairs.
4. Anthers purplish-black A. lessingii
4. Anthers yellow.
5. Heads characteristically discoid (rayless); a few marginal corollas sometimes appear raylike A. parryi
5. Heads characteristically with ray and disk flowers, rarely rayless.
6. Pappus somewhat feathery, tawny or straw-colored.
7. Heads broad (wider than tall), subhemispheric A. mollis
7. Heads narrow, more or less top-shaped (taller than wide) A. diversifolia
6. Pappus finely-barbed, usually white or nearly so.
8. Leaves broad, basal ones 1-2.5 (rarely 3) times as long as wide.
9. Achenes short-hairy throughout; involucre densely white soft-hairy; leaves often heart-shaped A. cordifolia
9. Achenes glabrous below, or glabrous throughout; involucres with few or no long hairs; leaves various, stem ones seldom heart-shaped A. latifolia
8. Leaves narrow, basal ones 3-10 times as long as wide.
10. Achenes usually glabrous below, or glabrous throughout.
11. Heads usually 3-9, usually erect A. gracilis
11. Heads solitary (rarely 3), usually nodding.
12. Involucral bracts becoming glabrous above, scarcely glandular; achenes scarcely glandular; plants of N BC A. frigida
12. Involucral bracts with short-stalked glands throughout; achenes usually moderately glandular and stiff-hairy above; plants of SE BC A. louiseana
10. Achenes usually short-hairy throughout.
13. Lower stem leaves unstalked (sometimes very short-stalked); ray flowers minutely toothed or entire A. rydbergii
13. Lower stem leaves short- to long-stalked; ray flowers prominently 3-toothed.
14. Disk corollas densely stalked-glandular, sometimes also with glandless hairs A. fulgens
14. Disk corollas sparsely to densely hairy, scarcely glandular A. angustifolia

ARTEMISIA

1. Flowers all perfect; shrubs.
2. Leaves deeply divided into 3-5 segments A. tripartita
2. Leaves mostly entire or merely 3-toothed at the apex.
3. Leaves mostly entire, occasionally with 1 or 2 teeth or lobes A. cana
3. Leaves 3-toothed at the apex, the upper becoming entire A. tridentata
1. Marginal flowers female; herbs or shrubs.
4. Receptacle covered with long hairs.
5. Plants large, usually 0.4-1.2 m tall; the larger leaves 3-8 cm long A. absinthium
5. Plants small, usually 0.1-0.4 m tall; the larger leaves less than 3 cm long A. frigida
4. Receptacle glabrous.
6. Annuals or biennials from a taproot; leaves essentially glabrous A. biennis
6. Perennials from a rhizome, stem-base, or a taproot, leaves more or less hairy.
7. Leaves mainly basal; stem leaves few and reduced upwards.
8. Leaves densely silky-hairy, the ultimate segments abruptly sharp-pointed or obtuse A. furcata
8. Leaves loosely long-hairy, the ultimate segments with long-pointed or slender, tapered tips.
9. Heads relatively large, the disks 5-10 mm wide. A. norvegica
9. Heads smaller, the disks less than 4.5 mm wide. A. campestris
7. Leaves mainly on the stems.
10. Leaves usually with one or two pairs of stipule-like lobes at the base A. vulgaris
10. Leaves without stipule-like lobes at the base.
11. Leaves entire or merely lobed or toothed.
12. Leaves essentially entire, rarely pinnately lobed.
13. Stems clustered from a woody stem-base; plants of the Peace River drainage A. longifolia
13. Stems loosely clustered or solitary from spreading, creeping rhizomes; plants widespread.
14. Leaves white-woolly below A. ludoviciana
14. Leaves glabrous or occasionally long-hairy below but not woolly A. dracunculus
12. Leaves lobed or toothed.
15. Leaves narrow; plants somewhat shrubby at the base from a taproot or cluster of short roots; restricted to the interior of S BC A. lindleyana
15. Leaves broadly lanceolate to elliptic; plants herbaceous to the base, not taprooted, restricted to coastal BC A. suksdorfii
11. Leaves deeply divided or subpinnately cut to tripinnately cut.
16. Leaves bipinnately cut, often with the ultimate segments again toothed.
17. Involucres usually densely woolly-hairy A. ludoviciana
17. Involucres sparingly woolly-hairy or glabrous A. michauxiana
16. Leaves deeply pinnately divided.
18. Involucres narrow, higher than wide A. ludoviciana
18. Involucres relatively broad, wider than tall.
19. Herbs from a rhizome; leaves white woolly-hairy below and green to sparsely white-woolly above A. tilesii
19. Shrubs from a woody stem-base; leaves white woolly-hairy on both sides
A. alaskana

ASTER

1. Ray flowers either inconspicuous (only slightly exceeding the disk) or wanting; female flowers more numerous than the disk flowers; perennials.
2. Heads with ray and disk flowers, the ray flowers about 2 mm long, surpassing the short style A. frondosus
2. Heads disciform, the ray flowers essentially wanting, the corolla of the female flowers tubular, shorter than the styles A. brachyactis
1. Ray flowers usually conspicuous; female flowers usually fewer than the disk flowers; annuals.
3. Pappus distinctly double, with an outer series of very short bristles in addition to the principal bristles; heads solitary, narrow (less than 4 mm wide); plants of SE BC A. stenomeres
3. Pappus simple or occasionally double; heads, habit and range various but not precisely as in A. stenomeres.
4. Ray flowers few, 1-3, white, shorter than the pappus; plants of Vancouver Island and the Gulf Islands A. curtus
4. Ray flowers more numerous, 5 or more, white to pink, blue, violet or pinkish-purple, longer than the pappus; ranges various.
5. Ray flowers commonly 13, sometimes 8 or 21, white (or often pale purple in A. engelmannii); involucral bracts tending to be keeled; pappus often with a few short outer bristles.
6. Leaves large, mostly 15-35 mm wide; plants 60-150 cm tall; plants of the Cascade Ranges and eastward in S BC A. engelmannii
6. Leaves smaller, 4-13 mm wide; plants 20-50 cm tall; plants of C Vancouver Island A. paucicapitatus
5. Plants differing in one or more respects from those above.
7. Achenes 2-nerved, flattened; heads solitary; plants with the habit of Erigeron A. alpinus
7. Achenes mostly several-nerved; heads usually numerous; usually not with the habit of Erigeron.
8. Involucres and their stalks glandular.
9. Leaves thick, egg-shaped to elliptic, usually sharply toothed. A. conspicuus
9. Leaves thin, linear to lanceolate, entire to remotely toothed.
10. Leaves narrow, mostly 2-10 mm wide, entire A. campestris
10. Leaves broader, mostly 10-40 mm wide, remotely toothed, rarely entire A. modestus
8. Involucres and their stalks without glands (or apparently so).
11. Involucral bracts usually with purple tips and margins; disk corollas with the tube (basal part) equalling or surpassing the slender limb (the flaring upper part, including lobes); leaves rough at least beneath.
12. Leaves sharply toothed over nearly all of the margin; heads several to many; lowland plants of S Vancouver Island A. radulinus
12. Leaves entire or with relatively few small teeth towards the tips; heads few, upper montane to alpine plants throughout BC A. sibiricus
11. Involucral bracts without purple tips and margins (except in some forms of A. foliaceus); disk corollas with tube shorter than the limb; leaves not rough beneath.
13. Basal or lower stem leaves heart-shaped or somewhat heart-shaped and distinctly stalked A. ciliolatus
13. Basal or lower stem leaves not heart-shaped and usually unstalked or shortly-stalked.
14. Plants slender, leaves less than 1 cm wide; rhizomes slender, less than 2 mm thick; plants of cold bogs and lake margins A. borealis
14. Plants differing in one or more respects from the above.
15. Stems and branchlets hairy in decurrent lines from the leaf bases; inflorescence generally large and leafy A. lanceolatus
15. Stems and branchlets with uniform hairs, or if in lines, then uniform below the heads; inflorescence various.
16. Involucral bracts, at least the outer, with loose or crimped, minutely and abruptly spiny tips; ray flowers white (rarely pinkish to purplish).
17. Plants with a stout, woody base; stems glabrous or sometimes with long, spreading hairs; introduced in the lower Fraser Valley A. pilosus
17. Plants with short or long rhizomes or a woody stem-base; stems densely stiff- or long-hairy; native through most of BC but not in the lower Fraser Valley.
18. Plants with well-developed, creeping rhizomes; heads few to many, often solitary at the ends of branches which are rarely one-sided A. falcatus
18. Plants with a short rhizome or stem-base; heads numerous, usually swept to1-side on upwards-curving branches A. ericoides
16. Involucral bracts appressed to spreading, without abrupt spiny tips (rarely obscurely so in A. ascendens and A. chilensis); ray flowers usually blue to purple (pink or white in A. eatonii) 15
19. Involucres strongly graduated; outer involucral bracts spoon-shaped, or slightly so, and usually obtuse, not leafy.
20. Heads few to many in a nearly naked, narrow to closed inflorescence; middle stem leaves usually less than 1 cm wide and more than 7 times as long as wide; plants of SE BC A. ascendens
20. Heads usually numerous on leafy-bracted branches; middle stem leaves usually more than 1 cm wide and less than 7 times as long as wide, plants of SW BC A. chilensis
19. Involucres not strongly graduated or, if so, then not spoon-shaped or obtuse; involucral bracts abruptly sharp-pointed or tapering to a slender tip, or if obtuse, then the outer bracts leafy.
21. Achenes glabrous, or nearly so.
22. Leaves glabrous, or nearly so and tending to be glaucous; stems glabrous, or nearly so, sometimes reddish A. laevis
22. Leaves subglabrous to more usually hairy; stems stiff-hairy, especially in the inflorescence, usually reddish-purple A. puniceus
21. Achenes more or less hairy; herbage variously hairy to subglabrous, not glaucous.
23. Outer involucral bracts usually with papery (not green) margins near the base, the papery portion tending to be darkened, yellowish or brownish rather than white A. subspicatus
23. Outer involucral bracts with inconspicuous or no papery margins, the papery portion, if present, usually whitish or greenish.
24. Inflorescence a long, narrow, leafy panicle with numerous heads; ray flowers usually pink or white A. eatonii
24. Inflorescence few-headed, or if more, then shorter, more open, and flattened-paniculate; ray flowers usually blue or violet.
25. Leaves relatively narrowly lanceolate, the bases rounded but not clasping, the middle stem leaves less than 1 cm wide and more than 7 times as long as wide; involucral bracts small and narrow, never enlarged or leafy A. occidentalis
25. Leaves broadly lanceolate to egg-shaped, the bases sometimes with ear-like flanges at the base, clasping, the middle stem leaves mostly over 1 cm wide and less than 7 times as long as wide, some of the outer involucral bracts often more or less enlarged and leafy A. foliaceus
BALSAMORHIZA
1. Plants densely and softly hairy, the leaves silvery, especially below; involucres densely woolly-hairy; plants of SC and SE BC B. sagittata
1. Plants sparsely hairy, the leaves green; plants of SW BC (SE Vancouver Island) B. deltoidea

BIDENS
1. Leaves, except sometimes the lowermost, unstalked; outer involucral bracts mostly spreading or reflexed.
2. Leaves toothed to nearly entire; ray flowers greatly exceeding the involucres, rarely lacking B. cernua
2. Leaves pinnately 3-parted and toothed; ray flowers barely exceeding the involucres B. amplissima
1. Leaves stalked; outer involucral bracts ascending to erect.
3. Leaves simple, deeply incised or 3-lobed; stalks short, with winged margins B. tripartita
3. Leaves pinnate; stalks long, without winged margins.
4. Outer involucral bracts 5-8; disk flowers orange; achenes usually blackish B. frondosa
4. Outer involucral bracts 10-16; disk flowers pale yellow; achenes yellowish or brownish B. vulgata

BRICKELLIA

1. Leaves lance-linear to oblong or elliptic-oblong, entire or nearly so, unstalked B. oblongifolia
1. Leaves lanceolate to deltoid or heart-shaped, round-toothed to toothed, stalked B. grandiflora
CARDUUS
1. Heads large, 2-8 cm wide, nodding, solitary; involucral bracts 2-8 mm wide C. nutans
1. Heads smaller, 1-2.5 cm wide, ascending, often clustered; involucral bracts 1-1.5 mm wide.
2. Involucres hemispheric, 1.5-2.5 cm wide; outer involucral bracts somewhat leafy and spreading; plants strongly spiny C. acanthoides
2. Involucres egg-shaped, 1-1.3 cm wide; outer involucral bracts rigid, scarcely spreading; plants weakly spiny C. crispus

CARTHAMUS
1. Stem leaves toothed, weakly spined; corollas yellow to reddish-orange; achenes white C. tinctorius
1. Stem leaves more or less deeply lobed, rigidly spined; corollas yellow; achenes brown C. lanatus

CENTAUREA

1. Outer involucral bracts conspicuously spine-tipped.
2. Outer involucral bracts with a prominent terminal spine and two or more pairs of smaller lateral spines at the base; flowers yellow C. melitensis
2. Outer involucral bracts with the terminal spine without lateral spines at the base; flowers creamy, sometimes purplish, rarely yellow C. diffusa
1. Outer involucral bracts comb-like, tattered and nearly entire to entire at the tips, not at all spiny.
3. Stem leaves pinnately divided into linear to lanceolate, entire or pinnately cut segments C. scabiosa
3. Stem leaves simple or at most coarsely toothed, lobed or pinnately cut below.
4. Involucral bracts bearing conspicuous flagged tips, distinctly broader than the involucral bract base.
5. Involucral bract appendages papery and tattered C. jacea
5. Involucral bract appendages dark and comb-like.
6. Involucres cylindric, taller than wide C. nigrescens
6. Involucres round, as wide as tall.
7. Involucral bracts with enlarged, tattered or sometimes comb-like, light to dark brownish, often papery appendages at the tips, these wider than the bracts; sterile marginal flowers enlarged at the tips with 5 narrow lobes C. debeauxii
7. Involucral bracts with enlarged, broad, rounded, tattered to comb-like, black to dark brown appendages at the tips, these wider than the bracts; sterile marginal flowers lacking C. nigra
4. Involucral bracts lacking apical appendages.
8. Involucral bracts comb-like margins.
9. Involucres oblong, 8-10 mm tall, 4-6 mm wide; heads in a panicle-like arrangement on stiff, divergent branches C. paniculata
9. Involucres egg-shaped, 9-13 mm tall, 6-8 mm wide; heads in a corymb-like arrangement at the ends of branches. C. biebersteinii
8. Involucral bracts with tattered margins.
10. Involucres mostly 11-16 mm tall; pappus 3-4 mm long; leaves linear C. cyanus
10. Involucres 20-25 mm tall; pappus 0.5 mm long; leaves broadly lanceolate to elliptic
C. montana

CIRSIUM

1. Heads small; involucres 1-2 (rarely 2.5) cm tall; plants introduced.
2. Stems distinctly spiny-winged; plants with perfect flowers C. palustre
2. Stems not conspicuously spiny-winged; plants partly of male and female flowers C. arvense
1. Heads large; involucres more than 2 cm tall; plants native (except C. vulgare).
3. Leaves bristly-spiny above, stems distinctly spiny-winged C. vulgare
3. Leaves cobwebby to loosely woolly-hairy, woolly or nearly glabrous above, stems not spiny-winged.
4. Pappus of mature seeds exceeding the corollas by 1-10 mm C. foliosum
4. Pappus of mature seeds shorter than the corollas.
5. Heads large; involucres 3-5 cm tall C. drummondii
5. Heads small; involucres less than 3 cm tall.
6. Outer involucral bracts more than 2 mm wide at base, slightly if at all hairy and if so, then mainly marginal.
7. Outer involucral bracts strongly glandular; lowermost leaves deeply pinnately lobed more than 1/2 the width of the blade C. undulatum
7. Outer involucral bracts without glands; lowermost leaves shallowly pinnately lobed to 1/2 or less the width of the blade C. scariosum
6. Outer involucral bracts less than 2 mm wide at base, densely cobwebby.
8. Corollas white or creamy-white, rarely pinkish; involucral bracts greenish
C. hookerianum
8. Corollas purplish-red to purplish-pink; outer involucral bracts purplish.
9. Styles exceeding the corollas by at least 3 mm; achenes 5-6.5 mm long; leaves usually lobed more than 1/2 the width of the blade C. edule
9. Styles nearly equal to or exceeding the corollas by only 1.5 mm; achenes 4-4.5 mm long; leaves usually lobed less than 1/2 the width of the blade C. brevistylum

COREOPSIS
1. Disk flowers purplish or brown; ray flowers yellow with a brownish-purple base; native annuals
C. tinctoria
1. Disk flowers yellow; ray flowers yellow throughout; introduced perennials C. lanceolata

CREPIS
1. Introduced annual or biennial weeds; taproots relatively weak; leaves mainly stem.
2. Inner involucral bracts hairy within; mature achenes dark purplish-brown C. tectorum
2. Inner involucral bracts glabrous within; mature achenes mostly tawny or pale brown.
3. Achenes 1.5-2.5 mm long, involucres 5-8 mm tall; receptacles glabrous C. capillaris
3. Achenes 2.5-9 mm long, involucres 8-12 mm tall; receptacles fringed with small hairs.
4. Achenes 2.5-4 mm long, beakless C. nicaeensis
4. Achenes 4.5-9 mm long, beaked C. vesicaria
1. Native perennial species, not weedy; taproots well-developed; leaves mainly basal.
5. Stems and leaves glabrous, or more or less coarse-hairy, but not at all woolly.
6. Rays mostly 20-50 in each head; plants mostly 20-70 cm tall C. runcinata
6. Rays mostly 9-12 in each head; plants 5-30 cm tall.
7. Achenes beakless or short-beaked, the ribs broad, rounded, smooth or slightly wrinkled; plants 5-10 (or rarely 20) cm tall C. nana
7. Achenes beaked, the ribs narrow, roughly stiff-hairy at least above; plants mostly 10-30 cm tall C. elegans
5. Stems and leaves more or less woolly or short-hairy, sometimes also bristly or glandular stiff-hairy.
8. Involucres and lower stems bristly but not glandular C. modocensis
8. Involucres and stems sparsely bristly or, if evidently bristly, then the bristles gland-tipped.
9. Leaf segments linear or narrowly lanceolate, mostly entire; achenes generally greenish
C. atribarba
9. Leaf segments broader, mostly lanceolate or deltoid, some of them toothed; achenes yellowish or brownish to dark brown.
10. Involucres grey, short woolly-hairy or less often more or less glabrous; plants 20-70 cm tall C. intermedia
10. lnvolucres usually glandular-hairy; plants 10-30 cm tall C. occidentalis

ERICAMERIA
1. Ray flowers 1-5, rarely lacking in some heads; achenes glabrous E. bloomeri
1. Discoid; achenes short-hairy E. nauseosus

ERIGERON

1. Pappus of the disk flowers composed of 2 sets of bristles, the inner longer and fragile; pappus of the discoid bristles.
2. Leaves numerous, deeply toothed; plants mostly 60-150 cm tall E. annuus
2. Leaves few, usually entire; plants mostly 30-70 cm tall E. strigosus
1. Pappus of the disk and ray flowers alike, of bristles and sometimes with outer scales.
3. Stem leaves well-developed, gradually reduced upwards, usually lanceolate or wider; all (except E. glabellus) with prominently clasping leaf-bases; plants tall and erect, somewhat Aster-like.
4. Rays mostly 2-4 mm wide E. peregrinus
4. Rays mostly 1 mm wide or less.
5. Leaves coarsely toothed, ray flowers 0.2-0.6 mm wide E. philadelphicus
5. Leaves irregularly toothed to entire, ray flowers about 1 mm wide.
6. Uppermost leaves strongly reduced, linear; the middle ones usually smaller than the mostly persistent lowermost ones; leaves never clasping E. glabellus
6. Uppermost leaves gradually reduced, lanceolate; the middle ones usually as large as or larger than the mostly deciduous lowermost ones; leaves somewhat clasping.
7. Leaves and stem long-hairy E. subtrinervis
7. Leaves and stem glabrous to sparsely hairy E. speciosus
3. Stem leaves usually much reduced or lacking, mostly linear or oblanceolate; plants usually low and spreading, not Aster-like.
8. Leaves dissected, or at least some of them 3-forked or toothed or lobed at the apex.
9. Leaves 2-4 times divided in 3’s E. compositus
9. Leaves 3-forked, or at least some of them toothed or lobed at the apex.
10. Leaves 3-forked.
11. Leaf segments more than 1 mm wide, the stalks obviously wider at the apex; plants of SE BC E. trifidus
11. Leaf segments 1 mm wide or less, the stalks not wider at the apex.
12. Leaf lobes oblong to egg-shaped, the lobes regularly 3-forked and generally of the same size and shape; plants of Vancouver Island E. salishii
12. Leaf lobes linear to lanceolate or narrowly oblong, the lobes often irregularly
3-forked or of dissimilar size and shape on the same plant
E. compositus (var. discoideus)16
10. Leaves, or at least some of them, toothed or lobed at the apex.
13. Involucres glandular-hairy, the ray flowers 4-5 mm long E. pallens
13. Involucres moderately to densely long woolly-hairy, the ray flowers 8-11 mm long
E. lanatus
8. Leaves entire or with teeth not restricted to the apical region, never 3-forked.
14. Involucres long woolly-hairy; heads solitary.
15. Ray flowers yellow E. aureus
15. Ray flowers white, pink, blue or purple.
16. Hairs of the involucres with conspicuous, dark purplish crosswalls E. humilis
16. Hairs of the involucres with clear crosswalls or rarely some of the basal ones reddish-purple.
17. Plants with at least some well-developed stem leaves.
18. Rays 60-125, 10-15 mm long, 1-2 mm wide E. grandiflorus
18. Rays 100-200, 3-6 mm long, 0.3-0.6 mm wide E. uniflorus
17. Plants without stem leaves or with only a few, reduced ones.
19. Involucres glandular-hairy, the ray flowers 4-5 mm long E. pallens
19. Involucres moderately to densely long woolly-hairy, the ray flowers 8-11 mm long E. lanatus
14. Involucres variously hairy or glandular but not long woolly- hairy.
20. Ray flowers yellow E. linearis
20. Ray flowers white, pink, blue or purple.
21. Hairs of the stems appressed, ascending, or lacking.
22. Plants with long, trailing, sparsely leafy stolons E. flagellaris
22. Plants without stolons.
23. Basal leaves broadly oblanceolate E. peregrinus
23. Basal leaves linear to threadlike.
24. Plants 10-50 cm tall; stems densely hairy towards the base; heads few to numerous E. filifolius
24. Plants less than 10 cm tall; stems not more densely hairy at the base than above; heads solitary to few E. ochroleucus var. scribneri
21. Hairs of the stems widely spreading.
26. Plants freely branched.
27. Leaves long spreading-hairy, the hairs over 1 mm long; disk corollas over
3 mm long E. pumilus
27. Leaves short spreading-hairy, the hairs well under 1 mm long; disk corollas
2-3 mm long E. divergens
26. Plants simple or sparingly branched.
28. Basal leaves evidently triple-nerved.
29. Basal leaves rounded or obtuse at tip; stems rarely purplish at the bases E. caespitosus
29. Basal leaves abruptly sharp-pointed, stems usually purplish at the bases E. corymbosus
28. Basal leaves not triple-nerved or only very faintly so.
30. Upper stem leaves broadly oblanceolate to egg-shaped E. leibergii
30. Upper stem leaves linear to lanceolate.
31. Achenes densely hairy; ray flowers 24-45 E. poliospermus
31. Achenes not densely hairy; ray flowers 50-175.
32. Basal leaves numerous, oblanceolate; rays 125-175 E. glabellus
32. Basal leaves few, linear to lanceolate, rarely oblanceolate; rays
50-100 E. pumilus

EUPATORIUM
1. Leaves glabrous, saw-toothed, the teeth several; disk flowers 5-6, reddish-mauve or whitish E. cannabinum
1. Leaves with spreading, curly hairs below, saw-toothed, the teeth numerous; disk flowers 9-22, purple E. maculatum

EUTHAMIA
1. Inflorescence usually interrupted and elongate; plants glabrous and often glaucous; involucral bracts with long-pointed tips E. occidentalis
1. Inflorescence essentially flat-topped and compact; plants glabrous or hairy, never glaucous; involucral bracts obtuse to abruptly sharp-pointed, without long-pointed tips E. graminifolia

FILAGO
1. Stems branched, these forklike F. minima
1. Stems branched, these appearing random and mostly alternate, not forked above.
2. Heads in small (up to 1 cm across) clusters at the ends of branches; outer receptacular bracts woolly throughout F. arvensis

GALINSOGA
1. Pappus scales of disk flowers tapering to a long point; pappus of ray flowers present G. quadriradiata
1. Pappus scales of disk flowers rounded or blunt; pappus of ray flowers minute or lacking G. parviflora

2. Heads in larger (1-2 cm across) clusters in the leaf axils as well as at the ends of branches; outer receptacular bracts woolly only at the base F. vulgaris

GNAPHALIUM
1. Inflorescence narrow, dense, spikelike.
2. Plants perennials; leaves linear; involucres 5-7 mm tall; involucral bracts rounded to obtuse
G. sylvaticum
2. Plants annuals or biennials; leaves spoon-shaped or rounded; involucres 3-5 mm tall; involucral bracts abruptly sharp-pointed to long-pointed G. purpureum
1. Inflorescence flat-topped to rounded, not spikelike.
3. Heads small, the involucres mostly 2-4 mm tall; heads tight-clustered, leafy-bracted; plants 15 cm tall (rarely up to 30 cm tall), usually much branched.
4. Leaves linear to narrowly oblanceolate, woolly hairs appressed; involucral bracts discoloured to the tip in mature heads G. uliginosum
4. Leaves oblanceolate to oblong, woolly hairs notably looser; involucral bracts white to brownish with white tips G. palustre
3. Heads larger, the involucres mostly 4-7 mm tall; heads tight-clustered, not conspicuously leafy; plants mostly 20-90 cm tall, simple or moderately branched.
5. Plants more or less glandular-hairy, at least on the upper leaf surfaces G. viscosum
5. Plants more or less woolly-hairy, not at all glandular.
6. Plants perennials; leaves narrowly extending down the stem G. microcephalum
6. Plants annuals or biennials; leaves clasping G. stramineum

GRINDELIA
1. Involucral bract tips loose or spreading, but not regularly reflexed; plants hairy to sometimes nearly glabrous; of the west coast of BC G. integrifolia
1a. Stems smooth to sparsely hairy, rarely with stiff, translucent hairs; leaves entire to toothed, the teeth mainly
1a. Stems densely grandular, also with some stiff, translucent hairs, sometimes sparsely hairy; leaves with regular teeth 1-2.5 mm long G. hirsutula
1. Involucral bract tips regularly reflexed; plants glabrous; of the interior of BC G. squarrosa

HELIANTHUS
1. Plants annuals; receptacles flat or nearly so H. annuus
1. Plants perennials; receptacles convex to low-conical.
2. Involucral bracts strongly overlapping; the disks purple, rarely yellow H. rigidus
2. Involucral bracts loose; the disks yellow H. nuttallii

HIERACIUM

17
1. Leaves brownish-purple mottled or blotched H. maculatum
1. Leaves green.
2. Flower heads pale creamish to white or orange-red.
3. Flower heads pale creamish to white; stolons lacking; native species H. albiflorum
3. Flower heads orange-red; stolons present; introduced species H. aurantiacum
2. Flower heads yellow.
4. Plants with stolons; pappus hairs in a single series with a few shorter than the rest.
5. Heads solitary on unbranched stems H. pilosella
5. Heads 2 or more on at least some branched stems.
6. Heads 1-6; involucres 9-12 mm tall H. flagellare
6. Heads 7 or more; involucres 5-9 mm tall.
7. Stems and leaves glabrous or with scattered non-glandular hairs H. praealtum
7. Stems and leaves with numerous non-glandular or glandular hairs H. caespitosum
4. Plants without stolons; pappus hairs in 2 series.
8. Basal leaves absent or deciduous by flowering time.
9. Largest leaves more than 2 cm wide; upper leaves unstalked with a rounded or clasping base; leaf margins not rolled under H. sabaudum
9. Largest leaves less than 2 cm wide; leaves not clasping at the base; leaf margins rolled under H. umbellatum
8. Basal leaves present at flowering time.
10. Basal leaves not tapered into the stalks H. murorum
10. Basal leaves tapered into the stalks.
11. Stem leaves absent or single and reduced.
12. Involucres grey-hairy (the hairs starlike), also with some long, soft blackish hairs which may be gland-tipped, generally 1-3 mm long H. gracile
12. Involucres greyish, long soft-hairy, with soft, greyish hairs, these generally 3-5 mm long H. triste
11. Stem leaves several.
13. Leaves entire or nearly so; native species of undisturbed habitats in SC and SE BC H. scouleri
13. Leaves toothed; introduced species of disturbed habitats in SW BC H. lachenalii

HYPOCHAERIS
1. Annual; leaves essentially glabrous; strap-shaped flowers broad (twice as long as wide) and equal to the involucres; involucres 0.5-1.5 cm wide H. glabra
1. Perennial; leaves densely rough-hairy; strap-shaped flowers narrow (4 times as long as wide) and surpassing the involucres; involucres 2-4 cm wide H. radicata

IVA
1. Plants annuals; leaves long-stalked, coarsely toothed; heads not subtended by leaves I. xanthifolia
1. Plants perennials; leaves unstalked or more or less stalked, entire, heads axillary I. axillaris

LACTUCA

1. Achenes with only a median nerve on each face, occasionally with an additional pair of very obscure ones L. canadensis
1. Achenes prominently several-nerved on each face.
2. Perennials; fruiting involucres 15-20 mm tall; flowers blue L. tatarica
2. Annuals or biennials; fruiting involucres 9-15 mm tall; flowers yellow, blue or whitish.
3. Heads 5-flowered L. muralis
3. Heads 13- to 55-flowered.
4. Achenes with a long, threadlike beak 1-2 times as long as the body; pappus white; introduced species L. serriola
4. Achenes beakless or with a short, stout beak less than 1/2 as long as the body; pappus brownish; native species L. biennis

LEONTODON
1. Stems scaly-bracted and generally several-headed; pappus of feathery bristles; leaves glabrous or stiff-hairy with simple hairs L. autumnalis
1. Stems usually naked and single-headed; pappus with some shorter, merely finely-barbed outer bristles or scales, some of the marginal achenes without feathery bristles; leaves stiff-hairy with short, forked hairs L. taraxacoides

LEUCANTHEMUM
1. Leaves entire, mainly basal L. integrifolium
1. Leaves palmately lobed or pinnately cut or toothed, only the uppermost entire.
2. Leaves spoon-shaped, the uppermost usually incised; plants introduced throughout BC L. vulgare
2. Leaves mostly wedge-shaped, sometimes only toothed at the tips, the uppermost entire; plants native on the N BC Coast L. arcticum

MADIA

2. Plants branched from near the base; leaves opposite M. minima
2. Plants branched above; leaves alternate M. exigua
1. Involucres usually more than 5 mm tall; rays conspicuous.
3. Leaves opposite; disk flowers sterile M. madioides
3. Leaves alternate; disk flowers fertile.
4. Involucres spindle-shaped, 2-5 mm wide when pressed; ray flowers 1-5, 1.5-2 mm long
M. glomerata
4. Involucres egg-shaped or broadly urn-shaped, 6-12 mm wide when pressed; ray flowers usually
8-13, 3-7 mm long.
5. Plants with hairs and stalked glands throughout M. sativa
5. Plants mainly with hairs throughout and stalked glands only above the middle of the stem
M. gracilis

MATRICARIA
1. Heads discoid M. discoidea
1. Heads with ray and disk flowers, the ray flowers white.
2. Receptacle conic; achenes smooth on the outer surface M. recutita
2. Receptacle hemispheric; achenes wrinkled on the outer surface M. perforata

1. Involucres usually less than 4.5 mm tall; rays inconspicuous.
MICROSERIS
1. Plants perennials; strap-shaped flowers conspicuous, well exceeding the involucre; pappus parts 6-60.
2. Pappus of 30-60 brownish hairlike bristles; stems simple and naked M. borealis
2. Pappus of 15-20 white or tawny, feathery, bristle-tipped scales; stems simple, glabrous or scaly, sparingly branched and leafy towards the base M. nutans
1. Plants annuals; strap-shaped flowers inconspicuous, equalling or barely exceeding the involucre; pappus of 5 parts.
3. Pappus of 5 linear scales, each terminating in a shorter, hairlike bristle arising from a distinct notch in the scale apex; stems leafy below and branched at or near the base M. lindleyi
3. Pappus of 5 lanceolate scales, each terminating in a longer, hairlike bristle arising from the pointed scale; stems naked and simple M. bigelovii

PETASITES
1. Leaves distinctly lobed, or if toothed then rarely more than 15 teeth per side P. frigidus
1. Leaves shallowly to conspicuously coarse-toothed, usually with 20 or more teeth per side.
2. Basal leaves rounded to heart-shaped P. japonicus
2. Basal leaves triangular P. sagittatus

PRENANTHES
1. Lower leaves oblanceolate to elliptic, middle ones unstalked and more or less heart-shaped and clasping at the base P. racemosa
1. Lower leaves arrowhead-shaped or sometimes deltoid, middle ones short-stalked or unstalked and tapering to the base
2. Inflorescence round- to flat-topped P. alata
2. Inflorescence elongate P. sagittata

PSILOCARPHUS
1. Plants upright; leaves never spoon-shaped, usually oblanceolate to linear-oblong P. elatior
1. Plants prostrate and matted to ascending; leaves spoon-shaped, oblanceolate, lanceolate or oblong.
2. Well-developed receptacular bracts 1.3-2.5 mm long at maturity; leaves spoon-shaped or oblanceolate to oblong, not broadest near the base P. tenellus
2. Well-developed receptacular bracts 2.5-4 mm long at maturity; leaves lance-oblong or lance-triangular, usually broadest near the base P. brevissimus

RUDBECKIA
1. Leaves deeply pinnately cut into narrow segments; ray flowers yellow R. laciniata
1. Leaves merely toothed or nearly entire; ray flowers orange or yellow-orange R. hirta

SAUSSUREA

1. Receptacles naked; outer involucral bracts about as long as the inner S. nuda
1. Receptacles papery; outer involucral bracts shorter than the inner.
2. Stem leaves 0.2-1.2 cm wide, linear to lanceolate, entire to few toothed S. angustifolia
2. Stem leaves l-7 cm wide, egg-shaped to triangular or lanceolate, strongly toothed S. americana

SENECIO

1. Stem leaves well-developed, only gradually reduced upwards; basal leaves usually few at flowering time, seldom tufted.
2. Plants freely branched, decumbent to ascending S. fremontii
2. Plants unbranched below, erect.
3. Leaves entire to toothed.
4. Leaves triangular S. triangularis
4. Leaves lanceolate to rounded, tapering to the base, not triangular.
5. Leaves densely white-woolly below; involucres 20-45 mm wide; ray flowers 2.5-7 mm wide; maritime plants of NW BC S. pseudoarnica
5. Leaves glabrous, or nearly so, below; involucres 8-16 mm wide; ray flowers 1-2 mm wide; interior plants of N, E, or SC BC.
6. Involucral bracts conspicuously black-tipped; plants of N BC S. sheldonensis
6. Involucral bracts not conspicuously black-tipped, sometimes purplish or incon-spicuously black-tipped; plants of SW and SC BC S. elmeri
3. Leaves (at least some of them) prominently lobed or deeply cleft to 2-3 times pinnately cut.
7. Heads discoid (rayless) S. vulgaris
7. Heads with ray and disk flowers.
8. Involucral bracts inconspicuously to conspicuously black-tipped.
9. Leaves mostly 2-3 times pinnately cut; introduced in SW BC near the coast S. jacobaea
9. Leaves merely lobed and deeply cleft.
10. Stalks of the heads glabrous; achenes glabrous; plants native in E BC
S. eremophilus
10. Stalks of the heads sparsely to moderately long-hairy; achenes hairy; plants introduced in W BC S. sylvaticus
8. Involucral bracts not black-tipped.
11. Upper stems with long (over 1 mm) yellowish (sometimes whitish) hairs; plants native on moist sites in N BC S. congestus
11. Upper stems with glandular hairs; plants introduced on disturbed sites in coastal, SW and SC BC S. viscosus
1. Stem leaves progressively reduced upwards, or sometimes lacking; basal or lower stem leaves well-developed, often tufted.
12. Plants glabrous (although sometimes woolly when young but glabrous by flowering time) except for inconspicuous woolly hairs at the base, in the leaf axils, or in the inflorescence.
13. Leaves entire to toothed, not lobed, wavy, or pinnately cut.
14. Basal leaves usually entire, sometimes irregularly toothed.
15. Involucres glabrous; plants glaucous S. hydrophilus
15. Involucres hairy, at least at the base; plants hairy and becoming nearly glabrous but not glaucous S. integerrimus
14. Basal leaves (or at least some of them) regularly toothed.
16. Leaves relatively narrow, always less than 3 cm wide; plants common in the subalpine and alpine zones in BC east of the Coast-Cascade Mountains S. lugens
16. Leaves relatively wide, at least some of them more than 4 cm wide; plants of the montane and lower subalpine zones in SE BC S. hydrophiloides
13. Leaves (or at least some of them) lobed, wavy or pinnately cut.
17. Heads with ray and disk flowers (sometimes rayless forms occur but these mostly occur with the more abundant, normal plants with ray and disk flowers).
18. Heads usually several.
19. Basal leaves (or at least some of them) heart-shaped to round S. pseudaureus
19. Basal leaves elliptic to lanceolate.
20. Basal leaves entire to wavy-margined, rarely a few with evident teeth S. macounii
20. Basal leaves toothed.
21. Basal leaves numerous, usually 6 or more, relatively thick and firm, entire to toothed above the middle of the blade; plants of dry meadows or open coniferous forests S. streptanthifolius
21. Basal leaves few, usually 6 or less, relatively thin and lax, toothed almost to the base of the blade or nearly entire; plants of moist sites S. pauperculus
18. Heads solitary, or rarely 2.
22. Involucre bases glabrous.
23. Involucres scarcely to heavily purplish-tinged towards the tips, rarely purplish throughout; stems and leaves green; plants of extreme S BC S. cymbalarioides
23. Involucres dark purplish throughout; stems and leaves purplish; plants of the Queen Charlotte Islands S. cymbalaria
22. Involucre bases usually hairy.
24. Basal leaves toothed, never lobed, usually purplish S. moresbiensis
24. Basal leaves conspicuously 5-7-lobed, green Sinosenecio newcombei (formerly Senecio newcombei)
17. Heads discoid (sometimes forms with ray and disk flowers occur but these mostly occur with the more abundant, normal, discoid plants).
25. Disk flowers orange; involucral bracts purple throughout or in the upper 1/2; heads 1-6 or rarely 7-12 S. pauciflorus
25. Disk flowers yellow; involucral bracts green, sometimes purplish at the tip; heads 6-40 or rarely only 3-5 S. indecorus
12. Plants (or at least some of them) hairy at flowering time.
26. Involucres covered with purplish or brownish hairs S. atropurpureus
26. Involucres covered with white or yellowish hairs, or rarely glabrous.
27. Involucres large, the largest more than 12 mm tall; heads 1-6 S. megacephalus
27. Involucres smaller, the largest less than 12 mm tall; heads 1-many.
28. Basal leaves (or at least some of them) regularly toothed.
29. Involucral bracts conspicuously black-tipped. S. lugens
29. Involucral bracts not black-tipped, sometimes purplish or inconspicuously black-tipped.
30. Stems ascending; heads often nodding; plants of S BC S. elmeri
30. Stems erect; heads erect; plants of C or N BC.
31. Involucral bracts green throughout or purple in upper 1/2; plants of C BC
S. plattensis
31. Involucral bracts purplish throughout; plants of N BC S. yukonensis
28. Basal leaves entire, lobed, or wavy-margined, rarely irregularly toothed.
32. Ray flowers orange to orange-yellow S. fuscatus
32. Ray flowers yellow.
33. Heads 1-5.
34. Basal leaves (or at least some of them) deeply lobed; montane to alpine plants of NW BC S. ogotorukensis
34. Basal leaves usually wavy-margined, rarely lobed; alpine plants of SE BC
S. conterminus
33. Heads 5-many.
35. Leaves densely white-woolly to felty; plants of S BC east of the Coast-Cascade Mountains S. canus
35. Leaves woolly, but never densely white-woolly.
36. Involucral bracts not conspicuously black-tipped; plants of coastal SW BC S. macounii
36. Involucral bracts usually conspicuously black-tipped; plants of SC to SE BC S. integerrimus

SOLIDAGO
1. Plants with well-developed creeping rhizomes; stems more or less equally leafy, the lowest leaves not markedly different than the upper ones.
2. Stems short-hairy, at least above the middle; leaves short-hairy to nearly glabrous S. canadensis
2. Stems glaucous or glabrous below the inflorescence; leaves glabrous or rarely nearly glabrous.
3. Stems densely and nearly uniformly leafy throughout; leaves not much reduced upwards, glaucous, 0.5-2.0 m tall, the upper leaves lanceolate, sharply saw-toothed S. gigantea
3. Stems with upper leaves reduced, glabrous, not glaucous, 0.2-0.5 m tall, the upper leaves mostly linear, entire S. missouriensis
1. Plants with a mostly short, stout, woody rhizome or a branched stem-base; stems with the basal and lower stalked leaves much larger than the upper, reduced, unstalked ones.
4. Leaves densely and finely short-hairy with short, spreading hairs S. nemoralis
4. Leaves glabrous except for the sometimes hair-fringed margins.
5. Lowermost leaves with the stalk fringed with small hairs; heads in a flat- or round-topped inflorescence; involucral bracts not much graduated S. multiradiata
5. Lowermost leaves with the stalks not fringed with small hairs; heads in an elongate inflorescence; involucral bracts evidently graduated S. spathulata

SONCHUS
1. Perennial herbs from deep-seated roots; heads relatively large, mostly 3-5 cm wide S. arvensis
1. Annual or sometimes biennial herbs from a short taproot; heads relatively small, mostly 1.5-2.5 cm wide.
2. Achenes several-nerved and wrinkled at maturity S. oleraceus
2. Achenes merely several-ribbed, not wrinkled S. asper

TANACETUM
1. Heads disciform, numerous, usually 20-200 T. vulgare
1. Heads with ray and disk flowers, few to many, usually less than 20.
2. Rays flowers white; leaves once or twice pinnately divided, the relatively broad segments often overlapping T. parthenium
2. Rays flowers yellow; leaves twice to three times pinnately divided, the segments not at all overlapping T. bipinnatum

TARAXACUM

1. Native, nonaggressive, high elevation species (except rarely along roads in extreme northern British Columbia) T. ceratophorum
1. Introduced, aggressive weedy species of disturbed sites.
2. Achenes red to reddish-brown or reddish-purple at maturity, the beak mostly 1-2 (sometimes 3) times as long as the body; leaves mostly deeply cut for their entire length, without an enlarged terminal segment, the lobes narrow; outer involucral bracts appressed to loose or sometimes reflexed; inner involucral bracts usually horned at the tips T. laevigatum
2. Achenes olive- or straw-coloured to brown at maturity, the beak mostly 2.5-4 times as long as the body; leaves usually less deeply cut, often with an enlarged terminal lobe; outer involucral bracts reflexed; inner involucral bracts not horned at the tips T. officinale

TOWNSENDIA
1. Heads usually on tall stems, the stems usually 10-35 (rarely less than 5) cm tall; involucral bracts without a tuft of tangled hairs at the tips; plants of the alpine zone T. parryi
1. Heads unstalked or on short stems usually less than 5 cm tall; involucral bracts usually with a tuft of tangled hairs at the tips; plants of the steppe and montane zones T. hookeri

TRAGOPOGON
1. Stalks of the heads cylindric, not enlarged above; outer ray flowers yellow, equal to or exceeding the involucral bracts T. pratensis
1. Stalks of the heads enlarged above; outer ray flowers yellow or purple, shorter than the involucral bracts.
2. Ray flowers purple; involucral bracts usually 8-9; leaves dilated and clasping at the base T. porrifolius
2. Ray flowers yellow; involucral bracts usually l3; leaves generally tapering evenly from the base to the tips T. dubius

TRIMORPHA
1. Rayless female flowers present between the rays and disk flowers; inflorescence round-topped; stalks of the heads curved upwards, or the head solitary T. acris
1. Rayless female flowers lacking; inflorescence elongate or nearly so; stalks of the heads erect or nearly so, or the head solitary T. lonchophylla