Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Silphium perfoliatum

Silphium perfoliatum var. connatum

cup plant, cup-plant rosinweed
Photo is of parent taxon

cup plant
Habit Plants caulescent, 75–300 cm; fibrous rooted.
Stems

square, glabrous, hispid, or scabrous.

glabrous or sparsely scabrous.
Leaves

basal caducous;

cauline usually opposite, rarely whorled (in 3s), petiolate or sessile;

blades deltate, lanceolate, or ovate, 2–41 × 0.5–24 cm, bases attenuate or truncate (distal connate-perfoliate), margins entire, dentate, or bidentate, apices acuminate to acute, faces scabrous to hispid.

Peduncles

glabrous.
Ray florets

17–35;

corollas yellow.

Disc florets

85–150 (–200);

corollas yellow.

Phyllaries

25–37 in 2–3 series, outer appressed, apices acute to acuminate, abaxial faces scabrous or hispid.

Cypselae

8–12 × 5–9 mm;

pappi 0.5–1.5 mm.

2n

= 14.

Silphium perfoliatum

Silphium perfoliatum var. connatum
Phenology Flowering summer–early fall.
Habitat River bottoms
Elevation 50–500 m (200–1600 ft)
Distribution
from FNA
AL; AR; CT; IA; IL; IN; KS; KY; LA; MA; MI; MN; MO; MS; NC; ND; NE; NJ; NY; OH; OK; PA; SD; TN; TX; VA; VT; WI; WV; ON
[WildflowerSearch map]
[BONAP county map]
from FNA
NC; VA; WV
[BONAP county map]
Discussion

Varieties 2 (2 in flora).

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

Variety connatum is known only from New River Valley.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Key
1. Stems glabrous or sparsely scabrous; peduncles glabrous
var. connatum
1. Stems glabrous, hispid, or scabrous; peduncles usually scabrous to hispid
var. perfoliatum
Source FNA vol. 21, p. 79. FNA vol. 21, p. 79.
Parent taxa Asteraceae > tribe Heliantheae > subtribe Ecliptinae > Silphium Asteraceae > tribe Heliantheae > subtribe Ecliptinae > Silphium > Silphium perfoliatum
Sibling taxa
S. albiflorum, S. asteriscus, S. brachiatum, S. compositum, S. glutinosum, S. integrifolium, S. laciniatum, S. mohrii, S. radula, S. terebinthinaceum, S. wasiotense
S. perfoliatum var. perfoliatum
Subordinate taxa
S. perfoliatum var. connatum, S. perfoliatum var. perfoliatum
Synonyms S. connatum, S. perfoliatum subsp. connatum
Name authority Linnaeus: Syst. Nat. ed. 10, 2: 1232. (1759) (Linnaeus) Cronquist: Brittonia 29: 223. (1977)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers