1. Ovary fully inferior
2. Lf parallel veined
3. Lvs fleshy, toothed, spine-tipped ..... AGAVACEAE (Agave)
3' Lvs not fleshy, entire, not spine-tipped
4. Fertile stamens 1–2, filament(s) and anther(s) wholly fused above ovary to stigma and style, forming a column; ovary with a half twist; ovules many, microscopic; seeds dust-like ..... ORCHIDACEAE
4' Fertile stamens 3 or more, not fused to stigma and style; ovary straight; ovules not microscopic; seeds well developed
5. Stamens 6; leaves not 2-ranked and folded (0 at flower in Amaryllis); adaxial and abaxial faces both visible ..... AMARYLLIDACEAE
5' Stamens 3; leaves 2-ranked, generally folded lengthwise and apparently attached "edge-on", only abaxial face of leaf visible ..... IRIDACEAE
2' Lf pinnately or palmately veined
6. Lvs basal, palmately veined and lobed, prickly — petiole 1–1.5 m, blade 1–2+ m ..... GUNNERACEAE {G14}
6' Lvs cauline, pinnately veined, entire or toothed, smooth
7. Lvs opposite; petals 2, 1–1.5 mm, white; fruit indehiscent, with hooked hairs ..... ONAGRACEAE (Circaea)
7' Lvs alternate; petals 3, yellow; fruit dehiscent, without hooked hairs
8. Petals 0.8–2.3 mm; leaves narrowly oblanceolate, 1–3 cm ..... ONAGRACEAE (Neoholmgrenia)
8' Petals >= 30 mm; leaves ± elliptic, 20–55 cm ..... ZINGIBERACEAE
1' Ovary superior or partially inferior
9. True leaves all scale-like, subtending thread-like to ovate leaf-like branchlets — erect to sprawling herb or twining vine ..... ASPARAGACEAE
9' True leaves not scale-like (except sometimes inflorescence bracts or basal leaves), not subtending leaf-like stems
10. Lvs needle-like, abaxially grooved; low shrub ..... ERICACEAE (Empetrum) {G7,9,12}
10' Lvs generally not needle-like, generally not abaxially grooved; herb to tree
11. Plant submersed aquatic; leaves very thin, 1-veined, opposite or whorled; flowers generally unisexual ..... HYDROCHARITACEAE (2) {G2,6,8}
11' Plant terrestrial, or if aquatic, leaves not very thin, 1-veined, and opposite or whorled
12. Lf venation pinnate or palmate, smaller veins generally forming a network (occasionally only midvein evident)
13. Tendrils present; vine; leaves ovate — flowers unisexual; plants dioecious ..... SMILACACEAE {G6,7,8,9}
13' Tendrils 0; herb, shrub, or tree (occasionally vine with twining stem); leaves various
14. Lvs compound or deeply lobed
15. Herb
16. Perennial; leaves basal, 2–3-ternate; petals in 2 tight whorls of 3; sepals in 4–5 whorls of 3 ..... BERBERIDACEAE (Vancouveria) {G20}
16' Annual; leaves cauline, 1-ternate or 1-odd-pinnate; petals 3; sepals 3 ..... LIMNANTHACEAE (Floerkea) {G10}
15' Shrub or tree
17. Trunk stout, unbranched, crowned by a tight terminal rosette of very large leaves ..... ARECACEAE
17' Trunk(s) branched, with leaves < 50 cm, distributed on twigs
18. Lvs alternate; leaflets spiny-toothed; fruit berry ..... BERBERIDACEAE (Berberis) {G20}
18' Lvs opposite; leaflets serrate; fruit winged achene ..... OLEACEAE (Fraxinus) {G7,9,12}
14' Lvs simple
19. Plant woody
20. Lf blade gland-dotted, aromatic; anthers dehiscing by uplifted lids; fruit fleshy ..... LAURACEAE {G12}
20' Lf blade not gland-dotted, not aromatic; anthers dehiscing by slits; fruit dry
21. Inner perianth parts 2, petal-like, outer minutely 4-lobed, ± green; fruit winged, 22–30 mm ..... OLEACEAE (Fraxinus parryi)
21' Inner and outer perianth parts in 3s, all petal-like; fruit 3-angled achene, < 5 mm ..... POLYGONACEAE (2) {G2,6,8,15,19}
19' Plant herbaceous
22. Fl bilateral, proximal portion of calyx with a protruding, hollow spur ..... BALSAMINACEAE {G24}
22' Fl radial, calyx without a spur
23. Cauline leaves in a whorl of 3 subtending 1 large terminal flower ..... MELANTHIACEAE (2) {G10}
23' Cauline leaves alternate, opposite, or whorled, sometimes reduced to bracts; flowers >> 1, small
24. Fr achene, (2)3-angled — inner and outer perianth generally similar, both whorls petal-like or both sepal-like (inner perianth parts much enlarged in fruit in Rumex) ..... POLYGONACEAE (2) {G2,6,8,15,19}
24' Fr capsule
25. Lvs not fleshy; plant ± aquatic; flowers axillary; outer perianth parts 2–3, ± = inner; stigmas 3; seeds many, surface net-like, brown to yellow-brown ..... ELATINACEAE (Elatine)
25' Lvs fleshy; plant terrestrial; flowers in ± 1-sided raceme-, panicle-, or umbel-like cluster; outer perianth parts 2, > inner; stigmas 2; seeds 1–many, shiny, black ..... MONTIACEAE (Calyptridium) {G24}
12' Lf venation parallel, sometimes in wider leaves several larger veins originating from leaf base but smaller veins parallel to them and not forming a network
26. Shrub, tree, or densely leafy rosette plant; leaves ± sword-like or ± grass-like, fibrous and/or fleshy, persisting > 1 year
27. Lvs grass-like; styles 3 ..... MELANTHIACEAE (Xerophyllum)
27' Lvs sword-like; style 1 or stigmas sessile
28. Ovules many per locule
29. Perianth creamy white; leaves tough, fibrous, entire or with marginal fibers ..... AGAVACEAE (2)
29' Perianth ± orange or red; leaves fleshy, toothed ..... ASPHODELACEAE (Aloe)
28' Ovules 2 per locule
30. Fls bisexual; fruit a berry ..... LAXMANNIACEAE
30' Fls generally unisexual (occasionally some bisexual); fruit a papery capsule ..... RUSCACEAE (Nolina) {G6,7,8,9}
26' Herb; leaves generally thin, generally not persisting (sometimes ± cylindric)
31. Sepals and petals clearly different
32. Plant aquatic, plant body submersed or leaves floating to emergent ..... HYDROCHARITACEAE (2) {G2,6,8}
32' Plant terrestrial
33. Above-ground stem 0, leaves 2–3(4), all basal; sepals much wider than narrowly linear petals; stamens 3; pedicels twisted, recurved in age; fruit touching soil ..... LILIACEAE (Scoliopus)
33' Above-ground stem well developed, ± leafy; sepals much narrower than reniform to generally widely ovate petals; stamens 6, sometimes 3 sterile; pedicels not recurved in age; fruit not touching soil
34. Petals glabrous, withering after 1 day; ovary ± spheric; seeds few ..... COMMELINACEAE
34' Petals hairy, generally persistent several days; ovary ± cylindric; seeds many ..... LILIACEAE (Calochortus)
31' Sepals and petals very similar
35. Perianth parts generally green to ± brown (red or white), scale-like
36. Infl of 1–many flowers, variously clustered, subtended individually and/or in small groups by bracts; style 1, stigmas 2–3, slender, spreading; fruit a capsule ..... JUNCACEAE {G13}
36' Infl a bractless raceme; stigmas 3 or 6, ± sessile; fruit breaking into mericarps ..... JUNCAGINACEAE {G2,10,13}
35' Perianth parts petal-like in color and texture
37. Infl an umbel (rarely flower solitary or in short, dense raceme); leaves all basal, arising from bulb or corm
38. Fr a berry ..... LILIACEAE (Clintonia)
38' Fr a capsule
39. Plant with onion odor; inflorescence bracts 2 (sometimes fused), wholly enclosing immature inflorescence, but generally not formed among pedicels; stems and leaves arising from bulb ..... ALLIACEAE {G1}
39' Plant without onion odor; inflorescence bracts 3 or more, not wholly enclosing immature inflorescence, and some formed among pedicels; stems and leaves arising from corm ..... THEMIDACEAE
37' Infl various, often a raceme or panicle, if flowers in umbels stem ± leafy or with scale-like bracts; leaves basal and/or cauline, underground parts various
40. Perianth parts proximally ± fused into tube
41. Plant aquatic, floating on water surface, stranded on mud, or rooting in bottom sediments; flowers generally open only 1 day ..... PONTEDERIACEAE
41' Plant generally terrestrial, sometimes in damp soil; flowers generally open > 1 day
42. Ovary underground; perianth tube long, stalk-like ..... AGAVACEAE (Leucocrinum)
42' Ovary above-ground; perianth tube not stalk-like
43. Perianth red (yellow) ..... ASPHODELACEAE (Kniphofia)
43' Perianth white to ± yellow
44. Perianth 45–60 mm; leaves strongly wavy-margined ..... AGAVACEAE (Hesperocallis)
44' Perianth 8–12 mm; leaves not wavy-margined ..... TECOPHILAEACEAE
40' Perianth parts free or nearly so
45. Lvs mostly or all cauline
46. Styles 3; flowers bisexual or staminate ..... MELANTHIACEAE (Veratrum) {G6}
46' Style 1 or stigmas sessile; flowers bisexual
47. Perianth 8–110+ mm ..... LILIACEAE (3)
47' Perianth 1–7 mm ..... RUSCACEAE (Maianthemum) {G15}
45' Lvs all basal or basal and cauline
48. All or some filaments densely hairy
49. Inner 3 filaments hairy ..... ASPHODELACEAE ([Bulbine])
49' All filaments hairy ..... NARTHECIACEAE
48' Filaments glabrous
50. Styles 3
51. St glabrous ..... MELANTHIACEAE (2) {G10}
51' St glandular ..... TOFIELDIACEAE
50' Style 1 or 0 and stigmas sessile
52. Cauline leaves present, ± well developed ..... LILIACEAE (3)
52' Cauline leaves 0 or reduced to linear or scale-like bracts
53. Lf lanceolate or ovate to elliptic or obovate ..... LILIACEAE (3)
53' Lf linear
54. Lvs ± flat, often keeled or wavy-margined; stem generally 1 from bulb ..... AGAVACEAE (2)
54' Lvs ± cylindric, hollow; stems several–many from tuber-like rhizome ..... ASPHODELACEAE (Asphodelus)
