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Indian breadroot, large Indian breadroot, prairie turnip

Nashville breadroot, white-rim scurfpea

Habit Herbs usually caulescent, rarely subacaulescent to acaulescent, to 50 cm, eglandular and pubescent throughout. Herbs acaulescent or subacaulescent, to 20 cm, eglandular except leaves or rarely stipules and bracts, pubescent.
Stems

erect, usually unbranched, sometimes branched basally, leaves dispersed along stem and arising nearly perpendicular to it;

pseudoscapes 0.5–2 cm;

cataphylls 0.5–15 mm, striate.

absent, leaves clustered;

pseudoscapes erect, 3–10 cm, usually 1, sometimes to 6, rarely branched proximally;

cataphylls 10–20 mm (when present).

Leaves

palmately (3–)5-foliolate;

stipules persistent, broadly lanceolate proximally to linear-lanceolate distally, 10–20 × 2–8 mm, stramineous basally, eglandular, glabrate to sparsely pubescent, hairs semi-erect;

petiole not jointed basally, (2–)30–100(–150) mm;

petiolules 1.5–4 mm;

leaflet blades elliptic to oblanceolate, 2–4(–6) × 0.7–2.3 cm, base attenuate to cuneate, apex broadly acute to rounded or retuse, surfaces abaxially pubescent, adaxially glabrate except on midvein.

palmately 5–7-foliolate;

stipules often fragmented on plant, partly connate, ovate, 11–24 × 11–16 mm, scarious, usually eglandular, sparsely pubescent;

petiole jointed basally, 40–150(–190) mm, shorter than peduncle, hirsute-villous;

petiolules 1–2.5 mm;

leaflet blades oblanceolate to elliptic, 1.5–4.5(–6) × 0.5–1.3(–1.8) cm, base cuneate, apex acuminate to obtuse, surfaces glandular, abaxially pubescent, adaxially sparsely so, usually along margins.

Inflorescences

persistent (not disjointing at base of peduncle in fruit), elliptic to oblong;

rachis 1.6–7 cm, elongating slightly in fruit, nodes (6–)8–15, (2 or)3 flowers per node;

bracts persistent, oblanceolate to elliptic, 5–15 × (0.5–)4–9 mm, glabrate to sparsely pubescent, hairs semi-erect.

disjointing in age at peduncle base, long-ovoid;

rachis 2.5–9.5 cm, elongating through fruiting, nodes 4–11(–15), 3 flowers per node, internodes 1–5 mm, elongating to 25 mm in fruit;

bracts persistent, orbiculate to lanceolate, 7–14 × 2–7 mm, margins pubescent, apex sometimes caudate or emarginate, becoming papery and veined in age.

Peduncles

(0.5–)5–12(–15) cm, shorter than subtending petiole, pilose.

4–14 cm (8–19 cm in fruit), longer than subtending petiole, setose.

Pedicels

1–3 mm.

1–2 mm.

Flowers

12–20 mm;

calyx strongly gibbous-campanulate in fruit, 13–16 mm abaxially, 12–14 mm adaxially, eglandular, pubescent;

tube 5–6 mm;

lobes linear or linear-lanceolate to elliptic, abaxial 7.5–10 × 2–2.5 mm, adaxial 4–7 × 1–1.5 mm;

corolla violet to blue-purple, banner sometimes paler, oblanceolate, 17–18 × 6 mm with claw 7–8 mm, wings 15–16.5 × 3–3.5 mm with claw 6–6.5 mm, keel 12–12.5 × 3 mm with claw 6–6.5 mm;

filaments 11–14 mm;

anthers elliptic, 0.5 mm;

ovary pubescent apically, style glabrous apically.

10–15(–22) mm;

calyx weakly gibbous-campanulate in fruit, 6–10 mm abaxially, 5–8 mm adaxially, glabrate and eglandular on gibbous portion, sparsely setose and glandular distally;

tube stramineous, 4.5–6 mm;

lobes triangular, abaxial 2–4 × 2 mm, adaxial 1–2 × 1 mm;

corolla dark blue to purple, banner oblanceolate to oval, 13–23 × 4–5 mm with claw 5–6 mm, wings 12–18 × 2–3 mm with claw 5–7 mm, keel 10–15 × 2–3 mm with claw 2–3 mm;

filaments 10–12 mm;

anthers obovate, 0.3 mm;

ovary pubescent apically, style pubescent basally.

Legumes

oblong, 4–6 × 2.5–3.5 mm, eglandular, pubescent, beak 9–13(–16) mm, exserted beyond calyx.

globose to ovoid, 6–7 × 4–5 mm, eglandular, sparsely pubescent apically, beak triangular, 4–6 mm, exserted beyond calyx.

Seed

brown, reniform, 4 × 3 mm, somewhat rugose.

gray-brown to red-brown, obovoid-reniform, 5–6 × 3–4 mm.

2n

= 22.

= 22.

Pediomelum esculentum

Pediomelum subacaule

Phenology Flowering late spring–summer. Flowering spring.
Habitat Prairies, grasslands, open pine woodlands. Calcareous soils, cedar glades.
Elevation 500–2000 m. (1600–6600 ft.) 200–1500 m. (700–4900 ft.)
Distribution
from FNA
AR; CO; IA; IL; KS; MN; MO; MT; ND; NE; NM; OK; SD; TX; WI; WY; AB; MB; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; GA; TN
[WildflowerSearch map]
[BONAP county map]
Discussion

Pediomelum esculentum was once one of the main sources of starch for Native American tribes of the Great Plains, eaten fresh, boiled, dried, or ground into flour and used as a thickening agent. Use of the root for food and barter was documented by Lewis and Clark on their historic expedition across the United States (Mer. Lewis and W. Clark 2003).

Pediomelum esculentum ranges in morphology from strongly caulescent to acaulescent with no apparent geographical structuring in this most widespread species. J. W. Grimes (1990) placed this species in subg. Pediomelum due to its persistent inflorescences. Molecular phylogenetic and network analyses suggest a split affinity for P. esculentum between both subgenera, suggesting that this may be an intermediate form and bridge between his subgenera or the groupings suggested by D. J. Ockendon (1965) based on habit—groupings somewhat supported by molecular phylogenies (A. N. Egan and K. A. Crandall 2008, 2008b).

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

Pediomelum subacaule is known from Colbert and Franklin counties in Alabama, Catoosa County in Georgia, and Davidson, Maury, Rutherford, and Wilson counties in Tennessee.

Pediomelum subacaule is quite distinct and disjunct from its fellow members of subg. Disarticulatum, this evidenced by its large, partly connate stipules and short, broad calyx lobes, and by being the only species in the subgenus east of the Mississippi River. Pediomelum subacaule is restricted to limestone soil in open cedar glades. Although P. subacaule is well established in the protected cedar glades of Tennessee, its historical range is shrinking due to habitat loss. Several historical sites that were, or still are, active limestone quarries have no remaining evidence of P. subacaule, particularly in Alabama and Georgia.

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

Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Pediomelum Fabaceae > subfam. Faboideae > Pediomelum
Sibling taxa
P. argophyllum, P. aromaticum, P. californicum, P. canescens, P. castoreum, P. cuspidatum, P. cyphocalyx, P. digitatum, P. epipsilum, P. humile, P. hypogaeum, P. latestipulatum, P. linearifolium, P. megalanthum, P. mephiticum, P. palmeri, P. pariense, P. pentaphyllum, P. piedmontanum, P. reverchonii, P. rhombifolium, P. subacaule, P. tenuiflorum, P. verdiense
P. argophyllum, P. aromaticum, P. californicum, P. canescens, P. castoreum, P. cuspidatum, P. cyphocalyx, P. digitatum, P. epipsilum, P. esculentum, P. humile, P. hypogaeum, P. latestipulatum, P. linearifolium, P. megalanthum, P. mephiticum, P. palmeri, P. pariense, P. pentaphyllum, P. piedmontanum, P. reverchonii, P. rhombifolium, P. tenuiflorum, P. verdiense
Synonyms Psoralea esculenta Psoralea subacaulis, Lotodes subacaulis
Name authority (Pursh) Rydberg in N. L. Britton et al.: N. Amer. Fl. 24: 20. (1919) (Torrey & A. Gray) Rydberg in N. L. Britton et al.: N. Amer. Fl. 24: 20. (1919)
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