Plants scapiform, (40–) 100–250+ cm; taprooted. Stems terete, glabrous. Leaves: basal persistent, petiolate; cauline alternate, petiolate or sessile; blades cordate, deltate, lanceolate, ovate, or sagittate, 3–40 × 1–40 cm, sometimes (proximal) pinnately lobed, bases attenuate, cordate, hastate, round, or truncate, ultimate margins coarsely toothed or entire, apices acuminate, acute, or obtuse, faces glabrous or scabrous. Phyllaries 23–33 in 2–3 series, outer appressed, apices obtuse to acute, abaxial faces glabrous. Ray-florets 17–29; corollas yellow. Disc-florets 120–140; corollas yellow. Cypselae 7–13 × 4–10 mm; pappi 0–1 mm.

Distribution

• Generated Map
• Legacy Map

Ont., Ala., Ark., Ga., Ill., Ind., Iowa, Ky., Mich., Miss., Mo., N.C., N.Y., Nebr., Ohio, S.C., Tenn., Va., Wis.

Discussion

Varieties 2 (2 in the flora).

Selected References

None.

Lower Taxa

Silphium terebinthinaceum var. pinnatifidum, Silphium terebinthinaceum var. terebinthinaceum

Key

1	Leaves pinnately lobed	Silphium terebinthinaceum var. pinnatifidum
1	Leaves not lobed	Silphium terebinthinaceum var. terebinthinaceum

"broader" is not a number.