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blood milkwort, blood or purple or field milkwort, field milkwort, polygale sanguin, purple milkwort

milkwort, polygala

Habit Herbs annual, single-stemmed, (0.5–)1–4 dm, usually branched distally; from taproot (or rarely fibrous root cluster). Herbs, annual, biennial, or perennial, or subshrubs [lianas, shrubs, trees], single- to multi-stemmed.
Stems

erect, glabrous.

mostly erect, sometimes lax to decumbent or prostrate [mat-forming], usually not glaucous, usually glabrous, sometimes pubescent or glabrate.

Leaves

alternate;

sessile or subsessile;

blade spatulate proximally to linear or narrowly elliptic distally, (5–)10–20(–40) × (0.5–)1–3(–5) mm, base acute or obtuse, apex acute to acuminate, surfaces glabrous.

basal and/or cauline, sometimes rosulate; usually alternate, sometimes opposite or whorled;

sessile, subsessile, or petiolate; usually uniform;

blade surfaces glabrous or pubescent.

Racemes

capitate to densely cylindric, (0.5–)1–2(–4) × 0.5–1.4 cm;

peduncle 0.3–2.5(–3) cm;

bracts subpersistent to tardily deciduous, subulate.

Inflorescences

terminal [axillary or leaf-opposed], racemes, sometimes in cymose panicles, or nearly spikes, [corymbs, fascicles, or 1–5-flowered], usually not interrupted;

peduncle present or absent;

bracts deciduous or persistent.

Pedicels

0.4–1.5 mm, glabrous.

usually present, usually glabrous.

Flowers

usually pink, purple, or reddish purple, rarely white, sometimes greenish tinged, sepals sometimes pink or white, 4–6 mm;

sepals oval, elliptic-ovate, or lanceolate, 1–3 mm;

wings ovate to broadly elliptic, (2.6–)4.5–6.3 × (1–)2.5–3.5 mm, apex obtuse to broadly rounded, sometimes minutely apiculate, rarely acute;

keel 2.5–3 mm, crest 2-parted, with 2–4 lobes on each side.

white, cream, green or greenish, pink, purple, reddish purple, blue, yellow, or orange, chasmogamous (some cleistogamous in P. crenata, P. lewtonii, and P. polygama), 1–9(–10) mm;

sepals persistent, glabrous (pubescent in P. alba and P. vulgaris), margins entire, sometimes ciliate or ciliolate;

wings persistent, 1–9 mm, glabrous (pubescent in P. alba), margins entire, sometimes ciliolate;

keel crested, crest 2-lobed, often fimbriate (lobes subdivided into fingerlike lobes), glabrous (pubescent in P. alba);

stamens (6–)8 in chasmogamous flowers, fewer in cleistogamous flowers, not grouped;

ovary 2-loculed (sometimes 1 abortive).

Fruits

capsules, dehiscent [indehiscent], margins winged or not, entire (crenately winged in P. crenata, erose-crenulate in P. hemipterocarpa), glabrous [pubescent].

Capsules

usually with flattened, sterile base, cuneate-subglobose, 2.5–3 × 2–2.5 mm, margins not winged (sometimes with raised rim).

Seeds

1.3–1.7 mm, pubescent;

aril 1–1.3 mm, lobes usually (1/2–)2/3 to ± length of seed, rarely minute.

coat without pits (except in P. hemipterocarpa, P. scoparioides, and P. watsonii), usually pubescent (hairs glochidiate in P. glochidata), usually arillate.

Polygala sanguinea

Polygala

Phenology Flowering spring–summer.
Habitat Prairies, old fields, gravelly logging road margins, meadows, glades, bogs, flatwoods, open woods.
Elevation 0–300 m. (0–1000 ft.)
Distribution
from FNA
AL; AR; CT; DC; DE; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NM; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; NB; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
from USDA
North America; Mexico; Central America; South America; West Indies; Europe; Asia; Africa; Australia
[BONAP county map]
Discussion

Polygala sanguinea is the only species of the genus in the flora area with the wings to twice the length of the keel. Late season flowers can have much smaller wings, some as small as 2.6 × 1 mm.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Species ca. 725 (31 in the flora).

Five non-native Polygala species have been reported for the flora area. Only P. vulgaris is truly naturalized; the other four, P. longicaulis Kunth, P. myrtifolia Linnaeus, P. paniculata Linnaeus, and P. serpyllifolia Hosé are historic waifs. Polygala serpyllifolia has been reported from Greenland (J. Devold and P. F. Scholander 1933) based on a single depauperate individual. Additional material has never been seen. Polygala paniculata was reported for Maryland by the USDA Plants database, but no specimens are known. It was reported also from Texas (D. S. Correll and M. C. Johnston 1970) but remains undocumented apart from a single specimen (Eggleston 17398, NY) collected in 1920 from Fort Davis in Jeff Davis County. Polygala myrtifolia is cultivated, especially in California and Florida, and is naturalized in Australia, Hawaii, and New Zealand. The USDA Plants website record for California is based on F. Hrusa et al. (2002), which was based on C. F. Smith (1976); however, the species was not listed by Smith (1998). Polygala longicaulis was collected only once, in 1917 from Jackson County, Alabama (ROCH). All four excluded, non-native species of Polygala are easily recognizable as part of the genus based on their fimbriate crests. They can be distinguished from the native Polygala species based on the following characters. Polygala longicaulis is separated by its obconic seeds densely covered in silky hairs, as well as the large, reddish to orangish resin dots medially on the sepals. Polygala myrtifolia would be the only shrubby Polygala in North America with a fimbriate crest. Polygala paniculata would look most similar to a robust P. glochidata, but lacks the glochidiate hairs on the seeds, usually has only the most proximal nodes with whorled leaves (often caducous by anthesis), and the stems are finely stipitate-glandular. Polygala serpyllifolia is very much like P. vulgaris but the proximal leaves are opposite or subopposite.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Capsule margins on abaxial locule not winged, adaxial locule longer and winged (sometimes not or obscurely winged in P. watsonii); seed coats with rows of pits (0.05 mm diam.); flowers white; racemes loosely flowered, cylindric or subcapitate; Arizona, New Mexico, Texas.
→ 2
2. Stems glabrous (rarely with a few scattered hairs).
P. hemipterocarpa
2. Stems puberulent or glabrate.
→ 3
3. Wing sepals (2.4–)2.7–4.5 mm; racemes cylindric (flowering portion may appear subcapitate from deciduous fruit), (1–)1.5–7.8 × 0.4–0.8 cm.
P. scoparioides
3. Wing sepals (3.5–)4–6 mm; racemes subcapitate, 0.5–1.4(–2.5) × 1 cm.
P. watsonii
1. Capsule margins not winged or narrowly and equally winged on both locules; seed coats without pits; flowers usually cream, green or greenish, pink, purple, reddish purple, blue, yellow, or orange, seldom white; racemes often densely flowered, sometimes spikelike or nearly so, capitate or cylindric; mostly e, n North America.
→ 4
4. Pedicels winged; flowers usually yellow, orange, green, or greenish, rarely white; racemes in cymose panicles or capitate.
→ 5
5. Racemes in cymose panicles, ± flat-topped; basal leaf blades obovate, spatulate, narrowly elliptic, linear-lanceolate, or linear, sometimes withered or nearly so at anthesis.
→ 6
6. Corollas pale yellowish apically, wing sepals white, cream, or, sometimes, greenish tinged; pedicels 0.6–1.2 mm.
P. balduinii
6. Corollas and wing sepals bright yellow; pedicels (1–)1.3–4 mm.
→ 7
7. Basal leaf blades linear-lanceolate to linear, forming large, persistent rosette; biennials, 4–12 dm.
P. cymosa
7. Basal leaf blades obovate or spatulate to narrowly elliptic, usually absent at anthesis; annuals or biennials, 1.5–4(–5) dm.
P. ramosa
5. Racemes solitary (not in panicles), capitate; basal leaf blades usually obovate, oblanceolate, linear-oblanceolate, or spatulate, rarely elliptic, often persistent.
→ 8
8. Flowers bright yellow to orange, drying pale yellow to dark greenish brown.
→ 9
9. Flowers bright orange, usually drying pale yellow; racemes (0.8–)1.2–2 cm diam.
P. lutea
9. Flowers bright yellow, drying pale yellow to dark greenish brown; racemes 1.8–2.5 cm diam.
P. rugelii
8. Flowers lemon yellow, greenish yellow, or green, sometimes drying green or yellowish green.
→ 10
10. Flowers lemon yellow to greenish yellow; wing sepals elliptic to oblong- lanceolate, tips 0.7–1.6 mm, apices involute; seeds 0.8–1.8 mm.
P. nana
10. Flowers green or greenish yellow; wing sepals usually lanceolate, sometimes oblong-lanceolate, tips 0.5–0.9 mm, apices usually flat to slightly involute; seeds 1.9–2.3 mm.
P. smallii
4. Pedicels not winged; flowers white, cream, green or greenish, pink, purple, reddish purple, or blue, not bright yellow or orange; racemes solitary (not in cymose panicles), sometimes spikelike or nearly so, cylindric, cylindric-conic, or capitate.
→ 11
11. Seed hairs glochidiate; leaves whorled (at least proximally); Arizona.
P. glochidata
11. Seed hairs not glochidiate; leaves usually whorled or alternate, rarely opposite or subopposite; widespread.
→ 12
12. Leaves whorled, at least at proximalmost 1 or 2 nodes.
→ 13
13. Perennials, multi-stemmed, with thickened caudices; flowers white or greenish white.
→ 14
14. Capsules ovoid, ellipsoid, or oblong, 1.3–1.6 mm diam.; w North America.
P. alba
14. Capsules subglobose to broadly ellipsoid, (1.2–)2–3 mm diam.; se United States.
P. boykinii
13. Annuals, single-stemmed (usually branched distally), with slender taproots or fibrous roots; flowers mostly pink or purple, sometimes white, greenish, or greenish white.
→ 15
15. Racemes spikelike or nearly so, cylindric, cylindric-conic, or conic; bracts deciduous; pedicels 0–1(–2) mm.
→ 16
16. Seeds glabrous.
P. leptostachys
16. Seeds pubescent.
P. verticillata
15. Racemes mostly capitate or apically rounded, sometimes cylindric; bracts persistent; pedicels (0.7–)1–2.4 mm.
→ 17
17. Wing sepals ovate to deltate, apices acuminate, often strongly cuspidate.
P. cruciata
17. Wing sepals ovate to ovate-oblong or ovate-oblanceolate, apices acute, short-mucronate.
→ 18
18. Wing sepals 1.5–2.5 mm wide; leaf blades 1–4(–7) mm wide.
P. brevifolia
18. Wing sepals 1.3–2 mm wide; leaf blades 0.5–1 mm wide.
P. hookeri
12. Leaves mostly alternate, proximal leaves sometimes opposite or whorled (in P. incarnata, P. lewtonii, and P. polygama).
→ 19
19. Cleistogamous flowers present, usually below, rarely just above, soil surface, sometimes in proximal leaf axils later in season; racemes loosely cylindric; short-lived perennials, biennials, or annuals, usually multi-stemmed, sometimes single-stemmed.
→ 20
20. Capsule margins winged.
P. crenata
20. Capsule margins not winged.
→ 21
21. Capsules ellipsoid or oblong, 2.5–3.5 × 1–1.5 mm, length 2–3 times width; flowers 6–8 mm; non-wing sepals 0.8–1.1 mm.
P. lewtonii
21. Capsules ellipsoid or globose-ovoid, 2–4 × 2–3 mm, length less than 2 times width; flowers 4–6 mm; non-wing sepals 1.3–2.5 mm.
P. polygama
19. Cleistogamous flowers absent; racemes sometimes spikelike or nearly so, often densely capitate or cylindric, sometimes cylindric-conic; mostly annuals, single-stemmed, sometimes perennials and single- or multi-stemmed.
→ 22
22. Leaf blades (1.5–)8–35 mm wide, margins often appearing serrulate (toothlike projections associated with marginal cilia.
P. senega
22. Leaf blades 0.3–2(–5.5) mm wide (rarely more than 4 mm); margins entire.
→ 23
23. Capsule margins narrowly winged; short-lived perennials, usually multi-stemmed (rarely 1 or few-stemmed) from small caudices; British Columbia, Michigan, Oregon.
P. vulgaris
23. Capsule margins not winged; annuals (sometimes perennial in P. setacea), single-stemmed, from taproots; s, e North America.
→ 24
24. Wing sepals less than 1/2 as long as keel petals; stems glaucous; arils scarcely lobed.
P. incarnata
24. Wing sepals usually (sub)equaling or exceeding keel petals, rarely slightly shorter; stems not or seldom glaucous; arils usually lobed, rarely vestigial.
→ 25
25. Leaf blades subulate scales, 0.5–1.6(–2) mm.
P. setacea
25. Leaf blades linear, linear-oblong, spatulate, oblanceolate, elliptic, linear-subulate, or subfiliform, 3–25(–40) mm.
→ 26
26. Wing sepals 1.5–2 times longer than keel petals; aril lobes (1/2–)2/3–nearly as long as seed.
P. sanguinea
26. Wing sepals equaling or slightly longer than keel petals (shorter in P. chapmanii, sometimes slightly shorter in P. mariana and P. nuttallii); aril lobes to 1/8–1/2 length of seed or vestigial.
→ 27
27. Bracts persistent (P. chapmanii often also with scattered deciduous ones).
→ 28
28. Racemes 0.4–0.7 cm diam.; wing sepals 2–3 mm; pedicels 0.5(–1) mm.
P. nuttallii
28. Racemes 0.6–1.3 cm diam.; wing sepals 2.5–5 mm; pedicels 0.7–2.8 mm.
→ 29
29. Wing sepals 2.5–3.3(–3.8) mm; capsules 1.5–2.3 mm.
P. chapmanii
29. Wing sepals 3–5 mm; capsules (1.7–)2.5–3 mm.
P. curtissii
27. Bracts deciduous (rarely a few persistent and scattered).
→ 30
30. Flowers white.
P. verticillata
30. Flowers usually pink or purple, rarely white.
→ 31
31. Racemes cylindric, 1.5–13 × 0.5–0.6 cm; flowers 1.6–2.2 mm; pedicels 0.8–1 mm.
P. appendiculata
31. Racemes capitate, (0.5–)1–3.5 × 0.6–1.1 cm; flowers 4–5.7 mm; pedicels 1.5–3.5 mm.
P. mariana
Source FNA vol. 10. FNA vol. 10.
Parent taxa Polygalaceae > Polygala Polygalaceae
Sibling taxa
P. alba, P. appendiculata, P. balduinii, P. boykinii, P. brevifolia, P. chapmanii, P. crenata, P. cruciata, P. curtissii, P. cymosa, P. glochidata, P. hemipterocarpa, P. hookeri, P. incarnata, P. leptostachys, P. lewtonii, P. lutea, P. mariana, P. nana, P. nuttallii, P. polygama, P. ramosa, P. rugelii, P. scoparioides, P. senega, P. setacea, P. smallii, P. verticillata, P. vulgaris, P. watsonii
Subordinate taxa
P. alba, P. appendiculata, P. balduinii, P. boykinii, P. brevifolia, P. chapmanii, P. crenata, P. cruciata, P. curtissii, P. cymosa, P. glochidata, P. hemipterocarpa, P. hookeri, P. incarnata, P. leptostachys, P. lewtonii, P. lutea, P. mariana, P. nana, P. nuttallii, P. polygama, P. ramosa, P. rugelii, P. sanguinea, P. scoparioides, P. senega, P. setacea, P. smallii, P. verticillata, P. vulgaris, P. watsonii
Synonyms P. viridescens
Name authority Linnaeus: Sp. Pl. 2: 705. (1753) Linnaeus: Sp. Pl. 1: 701. (1753): Gen. Pl. ed. 5, 315. (1754)
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