Plants lacking
chlorophyll (
holoparasitic ), with foliage and stems variously pink, purple, brown, tan, orange, or white.
Stem
paniculately branched; flowers
dimorphic , those low in the
inflorescences small,
pistillate , and fertile, those high in the
inflorescence larger, apparently
perfect but functionally
staminate ; [tribe
Orobancheae ]
Stem simple (rarely few-branched); flowers all alike.
Calyx deeply
cleft on the lower side;
stamens exserted ; [tribe
Rhinantheae ]
Calyx either nearly
regular , or deeply
cleft above and below into 2
lateral halves;
stamens included; [tribe
Orobancheae ].
Flowers solitary on a long
pedicel (appearing as a
scape , the true stem entirely underground or nearly so)
Flowers several-many,
sessile or subsessile in a dense
spike .
Calyx 5-
lobed , the
lobes subequal, all well-developed
Calyx 2-4-
lobed , rarely 5-
lobed , but then the fifth
lobe minute and much smaller than the other
lobes .
Calyx divided to the
base into 2
lateral halves, these usually 2-
lobed , the 4
lobes long-
attenuate or
caudate ; stem unbranched
Calyx tubular , with 4 (-5)
lobes about the length of the
calyx tube ; stem branched (except in
depauperate individuals)
Plants with
chlorophyll (hemiparasitic), with foliage and stems normally green.
Leaves
entire or 3-5-
lobed at the tip.
Bracts subtending flowers orange, red, or yellow;
calyx 4-
lobed ;
capsule loculicidal ;
pedicel lacking
bracteoles ; seeds broad, wingless; [tribe
Castillejeae ]
Bracts subtending flowers green;
calyx 5-
lobed ;
capsule septicidal and tardily also
loculicidal ;
pedicel with 2
bracteoles ; seeds narrow,
winged ; [tribe
Cymbarieae ]
Stem leaves (at least the lower) opposite.
Corolla salverform ; [tribe
Buchnereae ].
Plant
strict , unbranched unless damaged; flowers in a terminal
spike ;
corolla purple; [native, sometimes
weedy ]
Plant strongly branched; flowers solitary and
axillary ;
corolla red or orange; [
exotic , in agricultural fields]
Corolla various, but not
salverform .
Calyx 4-
lobed or essentially
unlobed ;
corolla strongly
bilabiate , the upper
lip consisting of 2
petals almost wholly
connate and strongly
cucullate (hooded);
corolla white or yellow; [tribe
Rhinantheae ].
Stem leaves
pinnately lobed , the
lobes rounded and themselves
crenate ; perennial, 3-8 dm tall
Stem leaves either
toothed with
acuminate teeth, or
entire (
bracteal leaves in and near the
inflorescence sometimes pectinately
fringed ); annual, 1-4 dm tall
Stem leaves
toothed with
acuminate teeth; seeds 10-18 per
capsule
Stem leaves
entire (
bracteal leaves in and near the
inflorescence sometimes pectinately
fringed ); seeds 1-4 per
capsule
Calyx 5-
lobed ;
corolla 5-
lobed , the
lobes relatively similar in size and shape, spreading;
corolla yellow, orange, red, or pink; [tribe
Gerardieae ].
Corolla pink; leaves
linear and thread-like (except
lanceolate in
A. auriculata )
Corolla yellow or orange; leaves either
lanceolate or broader, at least the
basal pinnately or
bipinnately lobed or
toothed , or
pinnately or bipinnately divided into
linear segments .
Leaves
pinnately or bipinnately divided into
linear segments up to 2 mm wide;
corolla rotate , the tube shorter than the
lobes
Leaves not
lobed or divided, or the
segments broader;
corolla tubular ,
campanulate , or
funnelform , the tube much longer than the
lobes .
Corolla orange,
tubular , the tube narrow and straight, > 5× as long as the diameter
Corolla yellow,
campanulate or
funnelform , the tube
conical , < 4× as long as the diameter.
Anthers pubescent ; lower leaves < 12 cm long
Anthers glabrous ; lower leaves 20-40 cm long
Inflorescence an
involucrate head subtended by
phyllaries , the heads solitary or many and variously arrayed in secondary
inflorescences , the
ovary inferior , the
corolla connate and
tubular at least basally, the
calyx absent, the
stamens 5, the fruit a
cypsela
Inflorescence , flower, and fruit structure various, but not with the combination of features as above (sometimes the flowers in a head subtended by
bracts , e.g.
Eryngium in APIACEAE, but then with other features differing, such as
stamens 4, or green
calyx present, or
petals separate, or fruit a
schizocarp of
mericarps , etc.).
Basal leaves 2-
lobed , hinged between the
lobes , each
lobe with stiff,
marginal , eyelash-like
bristles ; [Coastal Plain of NC and SC, rarely planted and weakly naturalized elsewhere]
Basal leaves 3-many-
lobed ,
palmately or
pinnately ; [collectively widespread].
Gynoecium of separate
pistils (each with a single
carpel ); fruit an aggregate
Gynoecium of a single
pistil (with 2, rarely more,
carpels ); fruit simple.
Stamens many;
sepals 2,
petals 4; fresh plants with yellow, orange, or white milky juice
Stamens 4, 5, or 6;
sepals 4 or 5;
petals 4 or 5.
Petals 4, distinct;
stamens 6
Petals 5, fused;
stamens 2, 4, or 5.
Corolla radially symmetrical;
stamens 5
Corolla 2-lipped, bilaterally symmetrical or asymmetrical;
stamens 2 or 4.
Corolla lobes not twisted, the flower bilaterally symmetrical;
stamens 2
Petiole attachment
peltate .
Leaves < 10 cm in diameter
Leaves > 15 cm in diameter
Petiole attachment
marginal .
Fruit
tuberculate ; leaves 3-
lobed
Fruit smooth; leaves with 5 or more
lobes
Ovary superior , or
half-inferior by
fusion of a
hypanthium a part of the way up the
ovary wall.
Gynoecium of separate
pistils (each with a single
carpel ); fruit an aggregate.
Perianth of 5 green
sepals and 5 colored
petals .
Carpels partly fused, arrayed in a ring of 10-20
Carpels separate,
spiral , many
Perianth of a single
whorl of 3-12
petaloid sepals (the
petals absent or small and
rudimentary ).
Leaves 2, the single flower terminal and associated with the upper leaf; fruit an aggregate of
berries
Leaves normally > 2, flowers not as above; fruit an aggregate of
achenes ,
utricles , or
follicles
Gynoecium of a single
pistil (with 1-5
carpels ); fruit simple.
Hypanthium present, partially fused or not fused to the
pistil ;
ovary partially
inferior to
superior
Petals connate at
base ; leaves sharply
toothed
Petals distinct; leaves with rounded
lobes or teeth.
Corolla radially symmetrical;
petals 8-12;
capsule fusiform , narrowed to both ends, > 5× as long as wide
Corolla bilaterally symmetrical;
petals 5;
capsule ovoid , < 2× as long as wide
Basal leaves not
lobed , at most
serrate or
crenate (and sometimes also
cordate ,
hastate ,
auriculate , or
peltate at the
base ).
Inflorescence a terminal and/or
axillary raceme ,
panicle , or
cyme of many small flowers; fruit an
achene ;
perianth uniseriate , of 0, 4-5, or 6
tepals .
Flowers
unisexual ;
staminate flowers 4-5
tepals ,
pistillate flowers lacking a
perianth
Flowers
bisexual ; flowers with 6
tepals
Inflorescence either a terminal
spike , or a 1-7-flowered terminal
cyme , or of a solitary
axillary or terminal flower; fruit various;
perianth biseriate (of differentiated
sepals and
petals (except
uniseriate , of 3 fused
sepals in ARISTOLOCHIACEAE).
Flowers bilaterally symmetrical;
inflorescence a terminal
spike (with > 20 flowers);
petals 4, usually
scarious , transparent;
sepals 4, green;
stamens 4
Flowers radially symmetrical;
inflorescence either of a solitary flower or of a 1-7-flowered terminal
cyme ;
petals 5, 8-12, or 0;
sepals 5 (green), 3 (brown), or 5-9 (yellow);
stamens 5, 12, or many.
Gynoecium of separate
pistils (each with a single
carpel ); fruit an aggregate of
achenes or
follicles ; flowers bright yellow, either of 5-9 distinct
petaloid sepals , or of 8-12 distinct
petals subtended by 3-4 green distinct
sepals
Gynoecium either of a single
pistil with 6
carpels or of a single
pistil with 4
carpels or of 2 nearly separate
carpels ; fruit a simple
capsule (or deeply 2-
lobed ); flowers white, brown, or greenish, either of 5 fused or distinct white
petals and 5 fused or distinct green
sepals , or of 3 fused brown or greenish
petaloid sepals .
Flowers brown or green, of 3 fused brown or greenish
petaloid sepals (and 0
petals );
carpels 6;
stamens 12; leaves 4-10 cm wide
Flowers white, of 5 white or whitish
petals and 5 green
sepals ;
carpels 2;
stamens 5; leaves 1-12 (-15) cm wide
Petals separate;
sepals separate; plant
glabrous
Petals fused (at least basally in
Dichondra );
sepals fused;
carpels 2; plant
pubescent .
Fruit a deeply 2-
lobed capsule ;
sepals longer or ca. as long as
petals ;
petals not
undulate , fused at their
bases or
distal ½, the
anthers maroon or brown-colored; [common, widespread in our area]
Fruit a fleshy
berry ;
sepals shorter than the
petals ;
petals undulate , fused, the
anthers yellow; [rare
exotic ]
Gynoecium of separate
pistils (each with a single
carpel ); fruit an aggregate;
perianth of 5 green
sepals and 5 colored
petals (or of 2 or 4 (-5) white-colored
tepals in
Begonia ).
Flowers typically with 2 or 4 (-5) white-colored
tepals ; leaf
bases conspicuously
oblique (sometimes
variegated ); fruit unequally or subequally 3-
winged capsules ; [ornamental
waifs or uncommon non-natives]
Flowers with 5 green
sepals and 5 colored
petals (not merged into
tepals ); leaf
bases oblique or not; fruit various but not 3-
winged capsules ; [natives and non-natives].
Carpels 10-20, partly fused, arrayed in a ring;
petals white, pink, red, or purplish
Carpels many, separate,
spiral ;
petals yellow or white.
Flowers lacking a
hypanthium ; fruit an aggregate of
achenes or aggregate of
follicles
Flowers with a
hypanthium ; fruit an aggregate of
drupelets or aggregate of
achenes
Gynoecium of a single
pistil (with 1-5
carpels ); fruit simple.
Flowers bilaterally symmetrical;
inflorescence of a solitary flower; fruit a 3-
locular capsule
Flowers radially symmetrical;
inflorescence an
umbel (or
composite of
umbelliform units, or a terminal
panicle .
Inflorescence a terminal
raceme ;
perianth of 4 green
sepals and 4 white
petals ; fruit a
silique /
silicle ; fresh foliage in spring and summer with a strong garlic odor; larger leaves < 10 cm in diameter
Inflorescence a terminal
panicle ;
perianth of 6 cream-colored
petaloid sepals ; fruit a
winged achene ; fresh foliage lacking a garlic odor; larger leaves typically > 30 cm in diameter
Petiole attachment
peltate
Leaf
blades longer than wide, sharply V-
cleft at the
base and otherwise shallowly
denticulate
Leaf
blades as broad or broader than long,
cleft at the
base and also irregularly
serrate or
crenate around the
margin
Basal leaves
petiolate or not, with a
truncate , rounded, or
cuneate leaf
base .
Leaves
tubular , with a sutured
ventral flange , erect or
reclining , adapted as a pitfall for insects (flat,
phyllodial leaves sometimes present as well, common in the winter in some species, such as
S. oreophila )
Leaves flat, not sutured into a
tubular shape.
Stem leaves opposite;
perianth 5
-merous , at least the
corolla bilaterally symmetrical (barely so in VALERIANACEAE), or the parts curved so as to be asymmetrical (
Pedicularis in OROBANCHACEAE);
stamens 2, 3, or 4.
Corolla narrowly
tubular , the five
lobes flaring at nearly 90 degrees and nearly radially symmetrical
Corolla distinctly 2-lipped (with prominently large upper and lower
corolla lobes ) or hooded (the upper
lip hood -like), distinctly bilaterally symmetrical, or the
lobes twisted so as to make the
corolla asymmetrical.
Corolla yellow, the upper
lip often slightly to strongly maroon, hooded but the
corolla lobes twisted so as to make the flower asymmetrical
Corolla white, lavender, or blue, 2-lipped and bilaterally symmetrical.
Sepals separate to the
base or nearly so, not forming a tube
Sepals connate for at least 0.3× their length to form a tube
Stem leaves
alternate ;
perianth radially symmetrical (less commonly bilaterally symmetrical);
stamens 5, 6-8, 9, 10 (rarely 4).
Pistils many, each with a single
carpel ; fruit an aggregate of
achenes
Corolla bilaterally symmetrical (barely so in
Limosella in SCROPHULARIACEAE);
stamens 2, 4, 6, 8, or 10.
Petals separate;
stamens 10
Petals fused;
stamens 10 or 6-8.
[plants of coastal wetlands]
[plants of uplands or inland
seeps or
fens ]
Flowers (and subtending
bracts ) red or yellow
Flowers purple, blue, or lavender
Corolla radially symmetrical;
stamens 5, 10, 4-6, or 9.
Perianth of green
sepals and more brightly colored
petals ;
stamens 5 or 10;
carpels 2, 3, 4, or 5.
Leaves covered with sticky,
gland -tipped
hairs (often red), as flypaper traps for insects
Leaves lacking sticky
gland -tipped
hairs .
Fruit a
schizocarp of 4
nutlets (
ovary obviously 4-
lobed in flower)
Fruit a
capsule or
silique /
silicle (or
utricle in
Limonium in PLUMBAGINACEAE).
Inflorescence of a solitary, terminal flower;
carpels 2-3 (-4).
Corolla with a long tube and flaring
corolla lobes (united > ½ its length)
Corolla of separate
petals or united only for a short length (< ¼ its length).
Inflorescence of several to many flowers;
carpels 5 (3 in
Galax in DIAPENSIACEAE).
Inflorescence an
umbel ;
petals recurved , pink to almost white
Fruit either a
capsule or a
utricle ;
petals 5;
stamens 5 or 10.
Inflorescence a somewhat to very
diffuse panicle , with 3 or more orders of branching, not giving at all the impression that the overall
inflorescence is made of
racemose units.
Leaves
entire ;
stamens 5; [plants of
tidal marshes ]
Leaves
serrate or
crenate ;
stamens 10; [plants of various habitats, especially rock outcrops and bottomland forests and streambanks, never in
tidal marshes ]
Inflorescence either a single terminal
raceme (sometimes
spike -like), or of 1 to several terminal and
axillary racemes (these sometimes combined into a
diffuse panicle , but one whose structure is clearly made up of many
racemes ).
Inflorescence of 1-several terminal and
axillary racemes , the plant typically well-branched, especially from the
base ;
stamens 5
Inflorescence of a single, terminal
raceme , the plant unbranched;
stamens 10 (or 5, with 5
staminodes )
Inflorescence spike -like, the flowers many (> 40), barely
pedicelled ;
capsule 3-
locular
Inflorescence a
raceme , the flowers fewer (< 20) and distinctly
pedicelled ;
capsule 5-
locular