=Indian Hemp, Apocynum cannabinum var. hypericifolium.=
ASCLEPIADACEAE, the Milkweed Family
Herbs, with simple entire leaves and regular flowers; juice usually
milky; except in the first species, which is a twining vine. The flowers
have an unusual structure: calyx of 5 sepals; petals 5, united with each
other, and spreading or reflexed so that they conceal the calyx; stamens
5, united with each other and with the stigma to form a complex organ in
the center of the flower; ovaries 2; on the back of each stamen is a
colored projecting hood, which is frequently the most conspicuous part
of the flower, and may be mistaken for the corolla.
1a. Twining vine, with dark purple flowers (summer)
=Black Swallow-wort, Cynanchum nigrum.=
1b. Stems not twining --2.
2a. Leaves whorled (3-6 dm. high; summer) (Milkweed) --3.
2b. Leaves opposite or alternate --4.
3a. Leaves in whorls of 4, lanceolate (flowers pink)
=Milkweed, Asclepias quadrifolia.=
3b. Leaves in whorls of 4-7, linear (flowers greenish-white)
=Milkweed, Asclepias verticillata.=
4a. Umbel sessile (4-8 dm. high; flowers green, summer)
=Green Milkweed, Acerates viridiflora.=
4b. Umbel peduncled --5.
5a. Leaves linear or narrowly linear-lanceolate (4-8 dm. high; flowers
greenish-white, summer) =Green Milkweed, Acerates floridana.=
5b. Leaves lanceolate or broader (flowers in summer) --6.
6a. Leaves pubescent beneath --7.
6b. Leaves glabrous or nearly so --10.
7a. Flowers brilliant orange (3-6 dm. high)
=Butterfly Weed, Asclepias tuberosa.=
7b. Flowers red or purple --8.
8a. Reflexed lobes of corolla merely purple-tinged (1-2 m. high)
=Milkweed, Asclepias syriaca.=
8b. Reflexed lobes of corolla bright-red or purple --9.
9a. The erect hoods of each flower about 5 mm. long (7-12 dm. high)
=Milkweed, Asclepias purpurascens.=
9b. The erect hoods of each flower about 3 mm. long (6-10 dm. high)
=Swamp Milkweed, Asclepias incarnata var. pulchra.=
10a. Leaves broadly rounded and almost sessile at base (flowers
purplish) --11.
10b. Leaves narrowed at the base, distinctly petioled (8-15 dm.
high) --12.
11a. Umbel solitary, terminal and erect on a long peduncle (4-8 dm.
high) =Milkweed, Asclepias amplexicaulis.=
11b. Umbels terminal or lateral, bent toward one side (7-12 dm. high)
=Milkweed, Asclepias sullivantii.=
12a. Corolla (not hoods) red (1-2 m. high)
=Swamp Milkweed, Asclepias incarnata.=
12b. Corolla (not hoods) greenish (8-15 dm. high)
=Milkweed, Asclepias exaltata.=
CONVOLVULACEAE, the Morning Glory Family
Twining or trailing herbs (except one species), with regular flowers;
sepals 5; corolla 5-angled or 5-lobed; stamens 5, attached to the
corolla; ovary superior, 2-3-celled.
1a. Plants with green foliage and conspicuous flowers (summer) --2.
1b. Leafless brown or yellow plants, with very small flowers (Dodder)
--7.
2a. Style divided at the top into linear or oblong stigmas (flowers
white or pink) (Bindweed) --3.
2b. Style not divided at the top; stigmas sessile, capitate
(Morning Glory) --6.
3a. Stem erect; leaves rounded or somewhat cordate at base, not hastate
or sagittate (1-3 dm. high) =Bindweed, Convolvulus spithamaeus.=
3b. Stem trailing or twining; leaves sagittate or hastate --4.
4a. Calyx almost concealed by two large heart-shape bracts --5.
4b. Bracts at base of calyx none =Bindweed, Convolvulus arvensis.=
5a. Leaves triangular-hastate, with sharp basal lobes
=Bindweed, Convolvulus sepium.=
5b. Leaves oblong-ovate, the basal lobes obtuse
=Bindweed, Convolvulus sepium var. pubescens.=
6a. Stem smooth or nearly so; ovary 2-celled (flowers white)
=Wild Potato Vine, Ipomoea pandurata.=
6b. Stem with reflexed hairs; ovary 3-celled (flowers of various
colors) =Morning Glory, Ipomoea purpurea.=
7a. Introduced weed, growing as a parasite on clover
=Dodder, Cuscuta epithymum.=
7b. Native species, on various shrubs and herbs --8.
8a. Flowers sessile --9.
8b. Flowers distinctly pedicelled --12.
9a. Sepals united below into a gamosepalous calyx --10.
9b. Sepals separate from each other --11.
10a. Calyx-lobes obtuse =Dodder, Cuscuta arvensis.=
10b. Calyx-lobes acute =Dodder, Cuscuta obtusiflora.=
11a. Flowers in dense rope-like twists on various species of herbs
=Dodder, Cuscuta paradoxa.=
11b. Flowers in dense clusters on various species of shrubs
=Dodder, Cuscuta compacta.=
12a. Tips of the petals inflexed =Dodder, Cuscuta coryli.=
12b. Tips of the petals erect or spreading --13.
13a. Capsule depressed at the summit =Dodder, Cuscuta cephalanthi.=
13b. Capsule pointed at the summit =Dodder, Cuscuta gronovii.=
POLEMONIACEAE, the Polemonium Family
Herbs with alternate or opposite leaves and conspicuous regular flowers;
sepals 5, united; petals 5, united and bearing the 5 stamens in the
corolla-tube; ovary superior, 3-celled.
1a. Leaves pinnately compound and alternate (2-4 dm. high; flowers blue,
in spring) =Greek Valerian, Polemonium reptans.=
1b. Leaves fascicled, narrowly linear (about 1 dm. high; flowers
pink-purple, in spring) =Moss Pink, Phlox subulata.=
1c. Leaves simple, strictly opposite --2.
2a. Corolla-lobes deeply 2-cleft to the middle (1-2 dm. high;
flowers pink, in spring) =Cleft Phlox, Phlox bifida.=
2b. Corolla-lobes entire and rounded, or somewhat notched at the
apex --3.
3a. Flowers in summer (8-15 dm. high; flowers purple)
=Garden Phlox, Phlox paniculata.=
3b. Flowers in spring (3-6 dm. high) --4.
4a. Corolla blue-purple; stems ascending
=Sweet William, Phlox divaricata.=
4b. Corolla pink or red-purple; stems erect
=Sweet William, Phlox pilosa.=
HYDROPHYLLACEAE, the Water-leaf Family
Herbs with alternate lobed or divided leaves and regular flowers; sepals
5; petals 5, united; stamens 5, attached to the corolla-tube and
projecting beyond it; ovary 1-celled.
1a. Leaves palmately veined and lobed (4-8 dm. high; flowers purple,
early summer) =Water-leaf, Hydrophyllum canadense.=
1b. Leaves pinnately veined and lobed (2-6 dm. high; flowers blue or
purple, varying to white) --2.
2a. Corolla-lobes much shorter than the corolla-tube (summer)
=Phacelia, Phacelia franklinii.=
2b. Corolla-lobes much longer than the corolla-tube (late spring
and summer) (Water-leaf) --3.
3a. Calyx with a small reflexed appendage between each pair of sepals
=Water-leaf, Hydrophyllum appendiculatum.=
3b. Calyx without appendages =Water-leaf, Hydrophyllum virginicum.=
BORAGINACEAE, the Borage Family
Herbs with alternate entire leaves; sepals 5; petals 5, united, corolla
generally regular; stamens 5, attached to the corolla-tube; ovary deeply
4-lobed with a single style.
1a. Corolla reddish-purple, about 8 mm. wide (4-10 dm. high; spring)
=Hound's Tongue, Cynoglossum officinale.=
1b. Corolla blue with a yellow center, 4-8 mm. wide (1-5 dm. high;
spring and early summer) (Forget-me-not) --13.
1c. Corolla deep orange, salver-form (2-6 dm. high; spring) (Puccoon)
--15.
1d. Corolla white or blue, or lightly tinged with yellow or red --2.
2a. Corolla rotate, with a very short tube, bright-blue, about 20
mm. broad (3-8 dm. high; summer) =Borage, Borago officinalis.=
2b. Corolla tubular, funnel-form, or salver-form --3.
3a. Corolla 10 mm. long or more; its tube distinctly longer than the
calyx --4.
3b. Corolla less than 10 mm. long; its tube equaling or shorter than the
calyx --8.
4a. Flowers yellowish-white, or somewhat tinged with pink or
greenish --5.
4b. Flowers blue or purple --6.
5a. Corolla-lobes erect; leaves sessile (3-8 dm. high; early summer)
=False Gromwell; Onosmodium occidentale.=
5b. Corolla-lobes spreading; leaves decurrent (6-10 dm. high; summer)
=Comfrey, Symphytum officinale.=
6a. Stem and leaves glabrous (3-6 dm. high; spring)
=Bluebell, Mertensia virginica.=
6b. Stem and leaves pubescent (4-8 dm. high) --7.
7a. Corolla regular; leaves ovate or ovate-lanceolate (summer)
=Bluebell, Mertensia paniculata.=
7b. Corolla irregular; leaves linear-oblong (summer)
=Blueweed, Echium vulgare.=
8a. Ovary and fruit covered with hooked prickles --9.
8b. Ovary and fruit not prickly --12.
9a. Principal leaves 2.5 cm. wide or more --10.
9b. Principal leaves 2 cm. wide or less (3-8 dm. high; flowers blue or
white, summer) (Stickseed) --11.
10a. Leaves chiefly basal, the racemes on long leafless peduncles
(4-8 dm. high; flowers pale blue, early summer)
=Wild Comfrey, Cynoglossum boreale.=
10b. Stems leafy (8-12 dm. high; flowers white, summer)
=Beggar Lice, Lappula virginiana.=
11a. A bract at the base of each flower =Stickseed, Lappula echinata.=
11b. Racemes without bracts at the base of each flower
=Stickseed, Lappula deflexa var. americana.=
12a. Racemes bractless, or bracted only at the base (1-4 dm. high)
--14.
12b. Raceme with a bract at the base of each flower (flowers white
or yellowish) --17.
13a. Corolla 4 mm. wide =Forget-me-not, Myosotis laxa.=
13b. Corolla 6-8 mm. wide =Forget-me-not, Myosotis scorpioides.=
14a. Calyx-lobes all of equal length (summer)
=Scorpion Grass, Myosotis arvensis.=
14b. Calyx-lobes distinctly unequal in length (spring)
=Scorpion Grass, Myosotis virginica.=
15a. Corolla-lobes denticulate =Puccoon, Lithospermum angustifolium.=
15b. Corolla-lobes entire --16.
16a. Flowers sessile; stem softly pubescent
=Puccoon, Lithospermum canescens.=
16b. Flowers on pedicels 2-5 mm. long; stem hispid or bristly
=Puccoon, Lithospermum gmelini.=
17a. Corolla white; fruit brown and wrinkled (weed 2-4 dm. high; spring
and summer) =Corn Gromwell, Lithospermum arvense.=
17b. Corolla yellowish-white; fruit white and smooth (5-10 dm. high)
--18.
18a. Corolla distinctly surpassing the calyx in length (spring and
summer) =Corn Gromwell, Lithospermum officinale.=
18b. Corolla equaling or shorter than the calyx (spring)
=Wild Gromwell, Lithospermum latifolium.=
LABIATAE, the Mint Family
Herbs with opposite leaves, square stems, and usually aromatic odor;
flowers irregular, with united petals, or almost regular; stamens 2 or
4, attached to the tube of the corolla; ovary deeply 4-lobed, with a
single style.
1a. Stamens 2 --2.
1b. Stamens 4 --15.
2a. Corolla regular or nearly so; flowers white, in dense axillary
clusters; plants usually of wet grounds (2-8 dm. high; summer
and autumn) --3.
2b. Corolla distinctly irregular and more or less 2-lipped --7.
3a. Calyx-teeth short, triangular, acute or obtuse (Bugle Weed) --4.
3b. Calyx-teeth narrow, acuminate or cuspidate (Water Hoarhound) --5.
4a. Stems and stolons bearing tubers
=Bugle Weed, Lycopus uniflorus.=
4b. Stems and stolons not bearing tubers
=Bugle Weed, Lycopus virginicus.=
5a. Leaves serrate; calyx-teeth sharp-pointed --6.
5b. Leaves coarsely incised; calyx-teeth awn-tipped
=Water Hoarhound, Lycopus americanus.=
6a. Corolla twice as long as the calyx; leaves narrowed at the base
=Water Hoarhound, Lycopus rubellus.=
6b. Corolla barely longer than the calyx; leaves sessile or nearly
so =Water Hoarhound, Lycopus lucidus var. americanus.=
7a. Corolla blue, 3-4 mm. long; flowers in loose axillary clusters (1-4
dm. high; summer) (Pennyroyal) --8.
7b. Corolla 8-40 mm. long --9.
8a. Leaves serrate =Pennyroyal, Hedeoma pulegioides.=
8b. Leaves linear, entire =Pennyroyal, Hedeoma hispida.=
9a. Lower lobe of the corolla fringed, very much longer than the upper
(5-15 dm. high; corolla pale-yellow; late summer)
=Horse Balm, Collinsonia canadensis.=
9b. Lower lobe of the corolla nearly or quite as long as the upper and
not fringed --10.
10a. Calyx narrowly tubular; its teeth about equal in size (5-10
dm. high; flowers in dense terminal heads, in summer) --11.
10b. Calyx campanulate, 2 of its teeth different in size from the
other 3 (4-8 dm. high; flowers pink-purple, in terminal
clusters in summer) --14.
11a. Corolla scarlet =Oswego Tea, Monarda didyma.=
11b. Corolla bright crimson or rose-red
=Wild Bergamot, Monarda fistulosa var. rubra.=
11c. Corolla white, pink, pale-purple, or yellowish --12.
12a. Flower-clusters all terminal --13.
12b. Flower-clusters both terminal and axillary
=Horse Mint, Monarda punctata.=
13a. Leaves and stem with soft spreading pubescence
=Wild Bergamot, Monarda fistulosa.=
13b. Leaves and stem grayish with fine appressed pubescence
=Wild Bergamot, Monarda mollis.=
14a. Upper calyx-teeth about 3 times as long as the lower
=Blephilia, Blephilia hirsuta.=
14b. Upper calyx-teeth but little longer than the lower
=Blephilia, Blephilia ciliata.=
15a. Calyx with a distinct protuberance on the back of the upper side
(Skullcap) --16.
15b. Calyx without a distinct protuberance --20.
16a. Corolla 5-8 mm. long; flowers in axillary racemes (3-8 dm.
high; flowers blue, in summer)
=Mad-dog Skullcap, Scutellaria lateriflora.=
16b. Corolla 6-10 mm. long; flowers axillary, solitary (1-3 dm.
high; flowers violet, early summer)
=Skullcap, Scutellaria parvula.=
16c. Corolla 12-30 mm. long; flowers axillary or in terminal
racemes (4-8 dm. high; flowers blue, summer) --17.
17a. Stem-leaves cordate =Skullcap, Scutellaria versicolor.=
17b. Stem-leaves not distinctly cordate --18.
18a. Stem-leaves sessile or nearly so; plant of swamps and
river-banks =Skullcap, Scutellaria galericulata.=
18b. Stem-leaves with petioles 1 cm. or more long; plants of dry or
moist woods --19.
19a. Stem glandular-pubescent toward the summit; corolla 16 mm. long or
less =Skullcap, Scutellaria pilosa.=
19b. Stem not glandular; corolla 20 mm. long
=Skullcap, Scutellaria incana.=
20a. Calyx-teeth 5, all equal or nearly so at the time of flowering
--28.
20b. Calyx-teeth 5, one of them different in size and shape from
the other four (2-6 dm. high; flowers light blue, summer)
=Dragon Head, Dracocephalum parviflorum.=
20c. Calyx-teeth 5, two of them different in size and shape from
the other three --21.
20d. Calyx-teeth 10, subulate (woolly plant 4-10 dm. high, with
whitish flowers in axillary clusters in summer)
=Hoarhound, Marrubium vulgare.=
21a. Corolla deeply split on the upper side and the stamens protruding;
upper lip of the calyx much shorter than the lower (5-10 dm. high;
flowers pink-purple, in terminal spikes, summer) (Wood Sage) --22.
21b. Corolla not deeply split on the upper side --23.
22a. Calyx canescent =Wood Sage, Teucrium canadense.=
22b. Calyx villous =Wood Sage, Teucrium occidentale.=
23a. Flowers in dense terminal head-like spikes, none axillary (1-5 dm.
high; flowers pink-purple or blue, in summer)
=Self-heal, Prunella vulgaris.=
23b. Some or all of the flowers in axillary clusters --24.
24a. Leaves linear, entire (1-4 dm. high; flowers purple, summer)
--25.
24b. Leaves oblong to ovate (summer) --26.
25a. Pedicels shorter than the calyx
=Summer Savory, Satureja hortensis.=
25b. Pedicels much longer than the calyx =Calamint, Satureja glabra.=
26a. Leaves 1 cm. long or less, entire (stems growing in mats, 1-3
dm. long; flowers purple, in summer)
=Wild Thyme, Thymus serpyllum.=
26b. Leaves dentate (flowers purple, summer) --27.
27a. Flowers subtended by bracts as long as the calyx (2-5 dm. high)
=Basil, Satureja vulgaris.=
27b. Flowers with minute bracts or none (1-3 dm. high)
=Basil-thyme, Satureja acinos.=
28a. Corolla 2-lipped or nearly regular, the upper lip flattened,
not conspicuously arched over the stamens --29.
28b. Corolla conspicuously 2-lipped, the stamens ascending under
the concave upper lip --42.
29a. Flowers in dense terminal spikes; corolla 2-lipped (8-15 dm. high;
summer) --30.
29b. Flowers peduncled, 1-4 in the axils of linear leaves --25b.
29c. Flowers in many-flowered whorls, which are axillary or terminal, or
aggregated into terminal spikes or racemes --31.
30a. Corolla yellowish =Giant Hyssop, Agastache nepetoides.=
30b. Corolla purplish
=Giant Hyssop, Agastache scrophulariaefolius.=
31a. Corolla distinctly irregular, the lower lip longer than the upper
--32.
31b. Corolla almost regular, the lobes nearly uniform in size --35.
32a. Stem-leaves sessile or very nearly so (flowers blue) --33.
32b. Stem-leaves long-petioled --34.
33a. Leaves linear-oblong, acute at both ends (3-8 dm. high; summer)
=Hyssop, Hyssopus officinalis.=
33b. Leaves oblong to ovate, rounded at the ends (2-4 dm. high; late
spring) =Bugle, Ajuga reptans.=
34a. Leaves ovate to oblong, acute; flowers pink, white, or pale
purple (6-15 dm. high; summer) =Catnip, Nepeta cataria.=
34b. Leaves nearly circular or kidney-shape; flowers blue
(creeping; flowers in spring and summer)
=Ground Ivy, Nepeta hederacea.=
35a. Flowers in terminal spikes, or the lower axillary (3-8 dm. high;
flowers pink-purple or white, summer) (Mint) --36.
35b. Flowers all in axillary whorls (flowers pink-purple or white,
summer) (Mint) --38.
35c. Flowers in terminal capitate corymbed clusters (4-8 dm. high;
flowers white or dotted with purple, summer) (Mountain Mint) --41.
36a. Leaves sessile or with very short petiole
=Spearmint, Mentha spicata.=
36b. Leaves with manifest petioles --37.
37a. Principal leaves less than half as broad as long
=Peppermint, Mentha piperita.=
37b. Principal leaves more than half as broad as long
=Bergamot Mint, Mentha citrata.=
38a. Stem glabrous; leaves ovate to obovate (4-8 dm. high)
=Downy Mint, Mentha gentilis.=
38b. Stem pubescent, at least on the angles (1-6 dm. high) --39.
39a. Principal leaves distinctly petioled and somewhat rounded at base
=Wild Mint, Mentha arvensis.=
39b. Leaves tapering to the base --40.
40a. Leaves and stem pubescent
=Wild Mint, Mentha arvensis var. canadensis.=
40b. Leaves glabrous; stem pubescent on the angles only
=Wild Mint, Mentha arvensis var. glabrata.=
41a. Leaves linear; calyx-teeth awl-shape
=Mountain Mint, Pycnanthemum flexuosum.=
41b. Leaves narrowly lanceolate; calyx-teeth triangular-ovate
=Mountain Mint, Pycnanthemum virginianum.=
42a. Stems decumbent to diffuse; leaves cordate to nearly circular
(stems 2-5 dm. long or high; flowers in spring and summer)
(Dead Nettle) --43.
42b. Stem erect; leaves palmately cleft; calyx-teeth spiny (6-15
dm. tall; flowers pink, in summer)
=Motherwort, Leonurus cardiaca.=
42c. Stems erect or ascending; leaves ovate-lanceolate to linear
(summer) --45.
43a. Upper leaves closely sessile (flowers red-purple)
=Dead Nettle, Lamium amplexicaule.=
43b. Leaves all petioled --44.
44a. Flowers red or purple =Dead Nettle, Lamium maculatum.=
44b. Flowers white =Dead Nettle, Lamium album.=
45a. Flowers 2-2.5 cm. long, in loose terminal spikes (5-10 dm. tall;
flowers rose-color) =False Dragon Head, Physostegia virginiana.=
45b. Flowers 1-2 cm. long, in axillary and terminal spiked whorls --46.
46a. Calyx-teeth spiny pointed (flowers pink or pale-purple) (Hemp
Nettle) --47.
46b. Calyx-teeth acute to awl-shape, but not spiny (3-10 dm. high;
flowers pale-purple) (Hedge Nettle) --48.
47a. Leaves ovate (3-8 dm. high) =Hemp Nettle, Galeopsis tetrahit.=
47b. Leaves linear to lanceolate (1-4 dm. high)
=Hemp Nettle, Galeopsis ladanum.=
48a. Leaves glabrous --49.
48b. Leaves distinctly pubescent --50.
49a. Leaves ovate-lanceolate, serrate
=Hedge Nettle, Stachys tenuifolia.=
49b. Leaves linear-oblong, entire or nearly so
=Hedge Nettle, Stachys hyssopifolia.=
50a. Stem pubescent on the angles alone; leaves petioled
=Hedge Nettle, Stachys tenuifolia var. aspera.=
50b. Stem pubescent on both sides and angles; leaves nearly sessile
--51.
51a. Leaves oblong or oblong-lanceolate, more than 1 cm. wide
=Hedge Nettle, Stachys palustris.=
51b. Leaves linear-lanceolate, 1 cm. wide or less
=Hedge Nettle, Stachys arenicola.=
VERBENACEAE, the Verbena Family
Herbs, with simple opposite leaves and slightly irregular flowers in
spikes or heads; petals 5, united and bearing the 4 stamens in the
corolla-tube; ovary 1, 2-celled or 4-celled, with 1 style.
1a. Plants prostrate or spreading --2.
1b. Plants erect (flowers in summer) (Vervain) --3.
2a. Leaves serrate; flowers in short dense spikes (flowers
pale-blue, summer) =Fog Fruit, Lippia lanceolata.=
2b. Leaves pinnatifid; flowers in loose bracted spikes (flowers
light-purple, summer) =Vervain, Verbena bracteosa.=
3a. Spikes dense, continuous (flowers purple or blue, varying to white)
--4.
3b. Spikes slender, interrupted, the flowers scattered (corolla white or
pale-blue) --6.
4a. Leaves lanceolate, manifestly petioled (1-2 m. high)
=Vervain, Verbena hastata.=
4b. Leaves sessile, not lanceolate (5-8 dm. high) --5.
5a. Leaves narrowly oblanceolate, tapering at the entire base
=Vervain, Verbena angustifolia.=
5b. Leaves oblong to obovate, not tapering at the base
=Vervain, Verbena stricta.=
6a. Leaves incised, tapering to a sessile base (5-10 dm. high)
=Vervain, Verbena, officinalis.=
6b. Leaves serrate, petioled (1-2 m. high)
=Vervain, Verbena urticaefolia.=
SOLANACEAE, the Nightshade Family
Herbs or shrubs, with alternate leaves and regular or slightly irregular
flowers; sepals 5, united; corolla of 5 united petals, bearing the 5
stamens attached; ovary 1, 2-5 (usually 2)-celled, with a slender style.
1a. Corolla rotate; anthers close together (flowers in summer) --2.
1b. Corolla not rotate; anthers separate --5.
2a. Stem and leaves prickly (3-8 dm. high) --3.
2b. Stem and leaves not prickly --4.
3a. Flowers white or bluish =Horse Nettle, Solanum carolinense.=
3b. Flowers yellow =Buffalo Bur, Solanum rostratum.=
4a. Climbing vine; leaves frequently lobed (flowers blue)
=Bittersweet, Solanum dulcamara.=
4b. Not climbing; leaves toothed (flowers white)
=Nightshade, Solanum nigrum.=
5a. Climbing or trailing shrub, with purplish, white, or greenish
flowers about 1 cm. wide (frequently thorny; flowers in summer)
=Matrimony Vine, Lycium halimifolium.=
5b. Herbaceous plants, not climbing --6.
6a. Flowers white, red, or blue, 2.5 cm. or more wide (summer) --7.
6b. Flowers yellow, yellowish-white, or greenish-yellow (summer)
--12.
7a. Corolla-tube 10 cm. long or more (5-12 dm. high) --8.
7b. Corolla-tube 5 cm. long or less --10.
8a. Stem finely pubescent; leaves entire or nearly so
=Thorn-apple, Datura metel.=
8b. Stem glabrous; leaves coarsely toothed (Jimson Weed) --9.
9a. Stem green; corolla white =Jimson Weed, Datura stramonium.=
9b. Stem purple; corolla light-blue or purple
=Jimson Weed, Datura tatula.=
10a. Corolla pale-blue (5-10 dm. high)
=Apple of Peru, Nicandra physalodes.=
10b. Corolla, red or violet (2-4 dm. high)
=Petunia, Petunia violacea.=
10c. Corolla white --11.
11a. Corolla all white (2-4 dm. high) =Petunia, Petunia axillaris.=
11b. Corolla with yellow center
=White Ground Cherry, Physalis grandiflora.=
12a. Corolla 30 mm. wide or more, somewhat irregular; stamens
declined to one side (3-6 dm. high)
=Henbane, Hyoscyamus niger.=
12b. Corolla smaller, strictly regular --13.
13a. Flowers in terminal panicles; corolla tubular, with slightly
spreading lobes (5-10 dm. high) =Wild Tobacco, Nicotiana rustica.=
13b. Flowers solitary in the axils; corolla short, widely spreading (3-8
dm. high) (Ground Cherry) --14.
14a. Annuals with branching slender roots --15.
14b. Perennials with thickened roots and rootstocks --16.
15a. Plants pubescent =Ground Cherry, Physalis pubescens.=
15b. Plants smooth, or with a few scattered hairs
=Ground Cherry, Physalis ixocarpa.=
16a. Stem viscid-pubescent =Ground Cherry, Physalis heterophylla.=
16b. Stem glabrous or slightly pubescent, not viscid --17.
17a. Leaves and stem distinctly pubescent
=Ground Cherry, Physalis virginiana.=
17b. Leaves and stem almost glabrous
=Ground Cherry, Physalis subglabrata.=
SCROPHULARIACEAE, the Figwort Family