Key - FSUS

Colors

Account

Support the Flora of the Southeastern US

2024 has been a banner year for making the best flora we can imagine. We've created:

Keys with embedded images of diagnostic features
Clickable glossary terms with illustrated definitions
FloraQuest: Carolinas & Georgia mobile app
Heliophily and Wetland Statuses
Direct links to Flora of North America
17,730 new high quality diagnostic photos and counting

With financial support from people like you, we are aiming even higher in 2025. Together we can accomplish all this: Vote on our 2025 priorities

Add Global Conservation Ranks (GRanks) vote
Professional graphic keys (polyclaves) to individual families/genera vote
2 new FloraQuest apps: Florida & Mid-South vote
Image overlays highlighting diagnostic characters with arrows vote
iNaturalist integration in FloraQuest vote

Write-in vote: vote

We've set a goal of recruiting 200 ongoing supporters to donate $15 or more each month in 2025. Please help us reach this goal and make next year's flora even better:

Donate $15 per month
(0.06¢/key line)

Donate $30 per month
(0.13¢/key line)

Donate $50 per month
(amazing!)

Donate another
or one-time amount

No key was found for the requested taxon, but it is the only child of Eriogonum. Showing where it is keyed below.

Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.

Key to Polygonaceae

Copy permalink to share

https://fsus.ncbg.unc.edu/main.php?pg=show-key.php&keyid=40201

1 Woody vine, climbing by tendrils; [subfamily Polygonoideae, tribe Coccolobeae].
2 Leaf base deeply cordate Antigonon leptopus
2 Leaf base truncate to broadly cuneate Brunnichia ovata
1 Herb (sometimes very robust and rather woody), herbaceous vine, tree or shrub (Coccoloba), or woody (Muehlenbeckia) or somewhat woody (Fallopia baldschuanica) vine lacking tendrils.
3 Tree or large shrubs (> 2 m tall when mature); bark of medium to mature trees peeling.
4 Leaves ovate to orbicular or sometimes lanceolate-elliptic (as in C. diversifolia); floral tube becoming fleshy, fruit not winged; [common in sandy coastal habitats, c. and s. FL] Coccoloba
4 Leaves long elliptic to widely lanceolate; floral tube not becoming fleshy; fruit 3-winged [rare escape, disturbed areas in s. FL] Triplaris melaenodendron
3 Herbs, herbaceous vines, woody vines, or small shrubs (< 2 m tall); stem not exfoliating.
5 Stem leaves (in our species) whorled; flowers in involucrate heads; ocreae absent; stamens 9; leaves densely white-tomentose on the lower surface; [of xeric situations of shale barrens and sandhills]; [subfamily Eriogonoideae, tribe Eriogoneae] Eriogonum
5 Stem leaves alternate; flowers in various inflorescences (not involucrate); ocreae present; stamens (3-) 5-8 (-9); leaves glabrous or variously pubescent, but not densely white-tomentose; [of various habitats, including xeric ones]; [subfamily Polygonoideae].
6 Tepals 6, in 2 series of 3 each; plants with leaves basally disposed, the largest basal (these withering in some species later in the season); [tribe Rumiceae].
7 Tepals (the outer series) spinose Emex spinosa
7 Tepals foliose.
8 Fruit 3-winged; basal leaves very large, 20-40 cm wide; inner and outer tepals similar; [plant cultivated, rarely persistent or escaped] Rheum rhabarbarum
8 Fruit 3-angled; basal leaves small to medium in size, 0.5-15 cm wide; inner tepals wider than the outer tepals; [plants common, mostly weedy]
9 Leaf blades of well-developed leaves (at least) hastate or sagittate; plants dioecious (rarely polygamo-monoecious), the flowers mostly unisexual; fresh foliage pleasantly acid to taste Acetosa
9 Leaf blades not hastate or sagittate; plants synoecious (rarely with some dioecious or polygamo-monoecious individuals), the flowers normally bisexual (sometimes bisexual and unisexual flowers in the same inflorescence); fresh foliage “green” or bitter to taste Rumex
6 Tepals mostly 5 in a single whorl; plants with leaves along the stem, lacking well-developed basal leaves.
10 Flowers in small clusters or very reduced racemes of 1-5 flowers, borne in the axils of normally sized or reduced leaves; plants erect or sprawling herbs with stems < 1 m long, from taproots; leaves jointed at base; [tribe Polygoneae].
11 Stems with 4 obscure ribs or angles (or lacking apparent ribs); leaf venation parallel, with inconspicuous secondary veins, longitudinally plicate; anthers pink-purple Duravia
11 Stems with 8-16 distinct ribs; leaf venation pinnate, the secondary veins apparent; anthers whitish yellow Polygonum
10 Flowers in diffuse axillary panicles, or in terminal or long-peduncled axillary racemes, corymbs, or heads; plants various, either erect or sprawling herbs, or erect, robust, and suffrutescent herbs, or climbing herbaceous, suffrutescent, or woody vines, or suffrutescent bushy herbs; leaves not jointed at base (except Polygonella).
12 Leaves cuneate at the base, either linear, spatulate, or oblanceolate, mostly < 4 cm long and < 5 mm wide; leaves jointed at the base; pedicels jointed at the base; [tribe Polygoneae] Polygonella
12 Leaves cuneate, cordate, or hastate at the base, either lanceolate or ovate, mostly > 5 cm long and > 8 mm wide; leaves not jointed at the base; pedicels not jointed at the base.
13 Inflorescence corymbiform, terminal; achenes strongly exserted at maturity; tepals almost free, horizontally spreading, white, 3-4 mm long; [erect annual, uncommonly cultivated and rarely persistent or escaped]; [tribe Persicarieae] Fagopyrum
13 Inflorescence paniculate, racemiform, or headlike, terminal and axillary; achenes enclosed in the perianth at maturity; tepals fused for much of their length, ascending, pink, green, or white.
14 Plants wiry-stemmed, woody vines with small leaves (< 2 cm long); flowers unisexual, the tubes of the pistillate flowers becoming fleshy in fruit Muehlenbeckia axillaris
14 Plants herbs or with thick, suffrutescent to woody, stems with larger leaves; flowers bisexual or unisexual (if unisexual, then the tubes of the pitillate flowers not becoming fleshy).
15 Outer tepals neither keeled nor winged at maturity; inflorescence of spikelike racemes, heads, or sparse, interrupted racemes; [tribe Persicarieae] Persicaria
15 Outer tepals keeled or winged at maturity; inflorescence a compound panicle of racemes; [tribe Polygoneae].
16 Plants erect, robust (1-4 m tall), woody, the stems generally over 1 cm in diameter, hollow; perianth enlarging in fruit; stigma fimbriate Reynoutria
16 Plants climbing or sprawling, herbaceous to somewhat woody, the stems slender; perianth usually not enlarging in fruit; stigma capitate or peltate
17 Ocreae smooth; perianth greenish to yellowish or pinkish; achene glossy or dull black; [mostly of lower elevations]. Fallopia
17 Ocreae reflexed bristly at the base; perianth white; achene glossy black; [of high elevation openings and woodlands] Parogonum ciliinode

Key P1: herbaceous dicots with alternate, simple, and unlobed leaves on the stem

Copy permalink to share | Check for keys that lead to this key

https://fsus.ncbg.unc.edu/main.php?pg=show-key.php&keyid=40740

1 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 Asteraceae
1 Inflorescence, flower, and fruit structure various, but not with the combination of features as above (sometimes the flowers in a head, e.g. Eryngium in APIACEAE, but then with other features differing, such as stamens 4, or green calyx present, or fruit a schizocarp of mericarps, etc.).
2 Perianth uniseriate (represented only by undifferentiated tepals or sepals) or completely absent; flowers usually unisexual, less commonly bisexual).
3 Inflorescence a cyathium, consisting of a single pistillate flower (reduced to a single 3-carpellate pistil) and 2 or more staminate flowers (each reduced to 1 stamen), borne in a cup-like involucre, the involucre bearing pointed or rounded glands, these sometimes brightly colored and petaloid, mimicking an individual flower (the cyathia then secondarily arranged in terminal cymes, or solitary and axillary, etc.); fresh plants with milky juice; fruit a 3-lobed, 3-locular capsule Euphorbia
3 Inflorescence not a cyathium (and staminate or bisexual flowers with > 1 stamen; fresh plants lacking milky juice (except Stillingia in EUPHORBIACEAE); fruit various, not as above.
4 Leaf margins toothed in some manner (serrate, dentate, crenate, etc.)
5 Leaf teeth rounded to subacute, resembling shallow lobes, irregular, few (mostly < 6 per leaf side).
6 Fruit a single-seeded achene or utricle; [plants of various disturbed or saline, usually sunny habitats] Chenopodiaceae
6 Fruit a 3-lobed, circumscissilely dehiscent capsule; [plants native of rich moist shaded forests or exotics in suburban woodlands] Pachysandra
5 Leaf teeth sharp to crenate, not lobe-like, regular, many (mostly > 10 per leaf side).
7 Leaf bases cuneate Euphorbiaceae
7 Leaf bases cordate to rounded.
8 Styles 3; fruit a 3-lobed, 3-carpellate capsule (1 carpel sometimes aborting); inflorescence either a terminal or leaf opposed raceme, or a dense axillary condensed cyme with conspicuous toothed bracts subtending the flowers Euphorbiaceae
8 Styles 1 or 2; fruit either an achene or a multiple of achenes; inflorescence either an axillary dense cyme (almost a head), or an axillary spike with glomerules, or a terminal or axillary panicle.
9 Styles 2; inflorescence a dense axillary cyme (almost a head); fruit a multiple of achenes; plant lacking stinging hairs; [exotic plant of weedy situations] Fatoua villosa
9 Style 1; inflorescence an axillary spikes with glomerules, or a terminal or axillary panicle; plant either with stinging hairs or not; [plant a rare exotic (Boehmeria nivea) or a native of moist forests (Boehmeria cylindrica, Laportea)] Urticaceae
4 Leaf margins entire.
10 Ovary inferior or half-inferior.
11 Leaf base cordate; calyx 3-lobed, fused into a bilaterally symmetrical, curved brown or yellowish tube; fruit a capsule Aristolochiaceae
11 Leaf base cuneate, rounded, or truncate; calyx of 3-4-5 distinct sepals, radially symmetrical, white or yellow; fruit a dry, nutlike drupe or an achene.
12 Leaves subsessile or very short petiolate, elliptic or narrowly elliptic, broadest near the middle; [native] Comandra
12 Leaves distinctly petiolate, rhombic, widest near the base; [rarely naturalized exotics].
13 Inflorescence of a single axillary flower Tetragonia tetragonoides
13 Inflorescence terminal, spikelike Beta
10 Ovary superior.
14 Inflorescence a leaf-opposed (sometimes apparently terminal) spike or raceme; flowers visually white from white petaloid sepals, white bracts, or white stamens.
15 Sepals present, 4 or 5; petaloid, white; carpels 1 to many (-12); stamens 4 to many (-25); fruit a berry or an apically 2-lobed achene (as in Petiveria); leaf bases cuneate or rounded (but not cordate); [Eudicots].
16 Sepals 4; carpels 1; fruit subglobose berries or apically lobed achenes Petiveriaceae
16 Sepals 5; carpels 6-12, distinct; fruit an oblate berry Phytolacca
15 Sepals absent; carpels 3-4; stamens 2-6 (-8); fruit a capsule, a 1-seeded drupe, or a schizocarp of 3-4 mericarps; leaf bases cordate or subcordate; [Basal Angiosperms].
17 Fruit a 1-seeded drupe; stamens 2; plants terrestrial or epiphytic Peperomia
17 Fruit a capsule or schizocarp with 3-4 mericarps; stamens 3 or 6-8; plants terrestrial Saururaceae
14 Inflorescence not leaf-opposed, either simpler (single axillary or glomerules of flowers) or more complexly branched (axillary or terminal panicles or complex cymes); flowers white, reddish, scarious, or greenish.
18 Stipules tubular, sheathing (= ocreae); flowers subtended by tubular, sheathing bracteoles (= ocreolae); nodes usually prominently swollen; perianth usually of 5-6 white to pink tepals Polygonaceae
18 Stipules not tubular or sheathing; flowers not subtended by ocreolae; nodes not swollen; perianth absent or of 3-5 sepals.
19 Inflorescence an terminal involucrate cluster; flowers bisexual; stamens 9 Eriogonum
19 Inflorescence axillary, or a terminal panicle or raceme that is not involucrate; stamens 3-6.
20 Ovary 3-locular; styles 3, each bifid; fruit a capsule, with 6 seeds Phyllanthaceae
20 Ovary 1-locular; styles 1-3, not bifid; fruit a utricle or achene (1-seeded).
21 Styles 1, stigma 1; flowers unisexual Parietaria
21 Styles 1-3, if style 1, then stigmas 3; flowers bisexual or unisexual.
22 Tepals acute, scarious Amaranthaceae
22 Tepals usually blunt, herbaceous Chenopodiaceae
2 Perianth biseriate (represented by differentiated whorls of sepals and petals, the sepals usually green or drab in color, the petals often brightly colored); flowers nearly always bisexual (there are exceptions).
23 Ovary inferior or half-inferior.
24 Petals connate.
25 Inflorescence leaf-opposed, a dense, cylindrical spike Sphenoclea zeylanica
25 Inflorescence various, either a terminal head, or axillary and solitary, or variously axillary or terminal and more diffuse.
26 Leaves toothed; flowers blue to white Campanulaceae
26 Leaves entire; flowers white Samolus
24 Petals distinct.
27 Petals 5; stamens 5; inflorescence a head; fruit a schizocarp of 2 mericarps Eryngium
27 Petals 4 7; stamens 6 or more; inflorescence various, not a head; fruit a capsule.
28 Petals 4-7; stamens 1× or 2× as many as the petals, 4-7, 8, 10, 12, or14; leaves herbaceous in texture Onagraceae
28 Petals 5 (or sometimes doubled in horticultural forms); stamens 6-40 (or more); leaves fleshy in texture Portulaca
23 Ovary superior.
29 Corolla bilaterally symmetrical, petals connate (except distinct in VIOLACEAE); fruit a capsule or legume (except a 1-seeded indehiscent spinose pod in Krameria in KRAMERIACEAE).
30 Petals distinct, 5; carpels 3; fruit a 3-loculed capsule Violaceae
30 Petals connate (at least basally), 4, 5, 6, 7, or 8; carpels 1, 2, 4, 5, or 6 (rarely 3 in Reseda in RESEDACEAE); fruit a legume or 1-, 2-, or 5-loculed capsule (except a 1-seeded indehiscent pod in Krameria in KRAMERIACEAE).
31 Stamens 6-10 (-25), more than the number (4 or 5) of petals and the number (4 or 5) of the sepals; fruit a legume or a 1-6-carpellate capsule.
32 Stamens fused, monadelphous or diadelphous.
33 Stamens 10, monadelphous or diadelphous; fruit a legume Fabaceae
33 Stamens 6-8, monadelphous; fruit a capsule Polygalaceae
32 Stamens distinct.
34 Carpel 1; fruit a legume Baptisia
34 Carpels 3-6; fruit a capsule Reseda
31 Stamens 4-5, less than the number (5) of the petals; fruit a 2-5-carpellate capsule.
35 Pistil 5-carpellate; capsule 5-locular, explosively dehiscent; inflorescence axillary, small clusters of flowers Impatiens
35 Pistil 2-carpellate; capsule 2 locular, opening gradually or not at all; inflorescence a terminal spike, raceme or panicle (or solitary, axillary flowers in Chaenorrhinum in PLANTAGINACEAE and Krameria in KRAMERIACEAE).
36 Fruit 1-seeded, indehiscent; sepals petaloid, red-purple; petals dimorphic, the upper 3 long-clawed, the lower 2 small, thickened, and glandlike Krameria
36 Fruit > 2-seeded, dehiscent; sepals sepaloid, green; petals not dimorphic.
37 Stamens 5; corolla not spurred; capsule septicidal; pubescence of the stem and leaves either gland-tipped or dendritically branched Verbascum
37 Stamens 4; corolla with a distinct spur or sac at the base between the the 2 lower calyx lobes (except not spurred in Digitalis and Schwalbea); capsule loculicidal (only at the summit in Antirrhinum and Chaenorrhinum, and septicidal in Schwalbea); pubescence of the stem and leaves neither gland-tipped (except in Antirrhinum and Chaenorrhinum) nor dendritically branched.
38 Capsule septicidal; corolla not spurred Orobanchaceae
38 Capsule loculicidal; corolla spurred (except Digitalis) Plantaginaceae
29 Corolla radially symmetrical, petals connate or distinct; fruit various (including a capsule).
39 Petals distinct; stamens 5-many.
40 Pistils 4-10 (each 1-carpellate) in a ring, these sometimes fused basally, each with its own style/stigma; fruit either an aggregate of achenes or follicles or a 5 (-7) locular capsule.
41 Pistils 5 (-7); inflorescence a compound terminal cyme.
42 Fruit an aggregate of follicles; leaves fleshy in texture; inflorescence; leaves entire of sparsely and coarsely serrate, with < 12 points per leaf; [plants primarily of dry habitats] Crassulaceae
42 Fruit a 5 (-7) locular capsule; leaves membranaceous in texture; leaves serrate, with > 20 points per leaf; [plants of wet habitats] Penthorum sedoides
41 Pistils many; inflorescence of solitary flowers, or diffuse.
43 Leaves cuneate at the base; flowers in a diffuse inflorescence Ranunculus
43 Leaves cordate at the base; flowers solitary, on long pedicels Dalibarda repens
40 Pistil 1, with 1-to many carpels (in many MALVACEAE, the carpels loosely united in a ring [of more than 5] around the single style/stigma); fruit either a 1-, 2-, 3-, 5-, 6-, or 10-locular capsule, or a silique/silicle, or a ring of mericarps.
44 Petals 4; sepals 4; stamens 6; fruit a silique/silicle Brassicaceae
44 Petals 5 (rarely 4 or 6); sepals 5 (rarely 4 or 6); stamens 5 (or multiples of 5), 6, or 12; fruit a capsule or a ring of mericarps.
45 Stamens many, connate into a staminal tube; carpels 5-many; fruit a capsule or ring of mericarps; leaves usually serrate Malvaceae
45 Stamens 5-many, distinct; carpels 2-5; fruit a capsule; leaves entire (serrate in Croton in EUPHORBIACEAE).
46 Flowers unisexual; leaf vestiture of peltate scales and/or stellate hairs Croton
46 Flowers bisexual; leaf vestiture simple or stellate.
47 Flowers 6-merous (the petals and sepals 6, the stamens 6 or 12); corolla pink or purplish (rarely white); fruit a septicidal capsule Lythrum
47 Flowers 5-merous (the petals and sepals 5, stamens 5 or various multiples of 5); corolla yellow, reddish, or blue; fruit a loculicidal or septicidal capsule.
48 Stamens 5; corolla yellow or blue; capsule either 10-locular and septicidal or 1-locular (with 3 carpels) and loculicidal.
49 Capsule 10-locular (with 5 carpels) and septicidal Linum
49 Capsule 1-locular (with 3 carpels) and loculicidal Turneraceae
48 Stamens (5-) 10, 15, 20, 30 (-many); corolla white, pink, yellow, or reddish; capsule 3-, 5- (-10)-locular, loculicidal.
50 Stamens (5-) 10, 15, 20, 30 (-many); corolla yellow or reddish; capsule 3 (-10)-locular, loculicidal Cistaceae
50 Stamens 10; corolla white or pink; capsule 5-locular Chimaphila
39 Petals fused; stamens (4-) 5 (-7).
51 Pistils 2, united only by the style and stigma; fruit a schizocarp of 2 follicles (often single by abortion); plant with milky juice when fresh; leaves entire; inflorescence an umbel Apocynaceae
51 Pistil 1 (of 2 or 3 fused carpels); fruit a capsule; plant lacking milky juice; leaves entire or serrate; inflorescence various (but not an umbel).
52 Ovary slightly to deeply 2-4-lobed; fruit a schizocarp of 4 mericarps or a drupe.
53 Ovary deeply 4-parted; style gynobasic; fruit a schizocarp of 4 mericarps Boraginaceae
53 Ovary slightly 2-4-lobed, or not at all lobed; style terminal or reduced to a sessile terminal stigma; fruit a schizocarp of 4 mericarps, or a drupe Heliotropiaceae
52 Ovary not lobed; fruit a capsule or berry.
54 Leaves scale-like, 1-4.5 mm long, appressed to the stem; petals 4; stamens 4 Bartonia
54 Leaves larger (or only 2-8 mm long in Pyxidanthera in DIAPENSIACEAE, but then spreading); petals 5-7; stamens 5-7.
55 Plant a creeping subshrub (keyed here as a failsafe); leaves either 0.2-0.8 cm long and acicular, or 2-10 cm long and broadly ovate or elliptic.
56 Leaves 0.2-0.8 cm long and acicular Pyxidanthera
56 Leaves 2-10 cm long and broadly ovate or elliptic Epigaea repens
55 Plant an herb, erect or sprawling; leaves > 1.5 cm long.
57 Leaves cordate at the base; plant a twining vine Convolvulaceae
57 Leaves cuneate to rounded at the base; plant an erect, sprawling, or reclining herb (twining in Solanum dulcamara in SOLANACEAE).
58 Inflorescences (solitary or of several flowers) terminal on the stem.
59 Corolla lobes longer than the fused corolla cup, blue, pink, or white; styles 2; herbage lacking stipitate glands; fresh plants not aromatic.
60 Flowers in axillary cymes; capsule subglobose; leaves 2-12 cm long Hydrolea
60 Flowers solitary or paired in the leaf axils; capsule cylindrical; leaves 0.5-8 cm long Nama
59 Corolla lobes very short, much shorter than the corolla cup or tube, sometimes barely perceptible and represented only by teeth on the edge of the corolla limb, white or pink; style 1; herbage often with stipitate glands; fresh plants often rankly aromatic Solanaceae
58 Inflorescences (of solitary or several flowers) axillary or lateral on the stem.
61 Flowers sessile or very-short pedicelled, solitary in the leaf axils.
62 Stamens alternate with the corolla lobes; flower ca. 10 mm in diameter Evolvulus
62 Stamens opposite the corolla lobes; flower ca. 1 mm in diameter Lysimachia
61 Flowers either solitary and obviously pedicelled, or several in an axillary or lateral inflorescence.
63 Corolla lobes longer than the fused corolla cup, blue Hydrolea
63 Corolla lobes very short, much shorter than the corolla cup or tube, sometimes barely perceptible and represented only by teeth on the edge of the corolla limb, white, yellow, pink, various other colors (rarely including blue).
64 Fruit a capsule, 4-seeded Convolvulaceae
64 Fruit a berry or capsule, many-seeded Solanaceae

Key Q: herbaceous dicots with whorled leaves on the stem {add [Platycodon] CAMPANULACEAE}