Spermatophytes (seed plants): Angiosperms (flowering plants): Eudicots: Core Eudicots: Asterids: Campanulids: Asterales
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (4/24/22):
Silphium reniforme
FAMILY
Asteraceae
Go to FSUS key
Dig deeper at SERNEC, a consortium of southeastern herbaria.
Read more about Ragged Rosinweed at Vascular Plants of North Carolina.
SYNONYMOUS WITH
PLANTS NATIONAL DATABASE:
Silphium compositum var. reniforme
FAMILY
Asteraceae
INCLUDED WITHIN Flora of North America north of Mexico, vol. 19-20-21 (2006)
Silphium compositum
SYNONYMOUS WITH VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 179-54-002b:
Silphium compositum var. reniforme FAMILY Asteraceae
SYNONYMOUS WITH Manual of the Southeastern Flora (Small, 1933, 1938)
Silphium reniforme
COMMON NAME:
Ragged Rosinweed, Kidneyleaf Rosinweed
To see larger pictures, click or hover over the thumbnails.
)
USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913 pnd_sire9_001_lvd
)
JK Marlow jkm130718_448
July McDowell County NC
The hickory leaves provide an idea of scale.
)
JK Marlow jkm230717_4450
July Greenville County SC
Blue Wall Preserve
Heads relatively small (disk 8-15mm wide), with 6-12 ray flowers, per Weakley's Flora (2023).
)
JK Marlow jkm230717_4452
July Greenville County SC
Blue Wall Preserve
Bracts wide, acute or obtuse, glabrous, ciliate or erose, usually squarrose, per Vascular Flora of the Carolinas (Radford, Ahles, & Bell, 1968).
COMPARE
involucral bracts of Silphium
)
JK Marlow jkm230717_4454
July Greenville County SC
Blue Wall Preserve
Leaves unlobed, coarsely dentate, often to 40cm wide, per Vascular Flora of the Carolinas (Radford, Ahles, & Bell, 1968).
)
JK Marlow jkm230717_4455
July Greenville County SC
Blue Wall Preserve
Leaves usually as wide as long or wider, per Vascular Flora of the Carolinas (Radford, Ahles, & Bell, 1968).
)
Will Stuart wil_5984487318_1bf6dc0684
July Burke County NC
Table Rock
)
Will Stuart wil_5984487650_b0764288c
July Burke County NC
Table Rock
The smooth purple stems of the plant are nearly naked.. — Will Stuart
)
JK Marlow jkm151024_573
October Greenville County SC
Blue Wall Preserve
)
JK Marlow jkm151024_578
October Greenville County SC
Blue Wall Preserve
)
JK Marlow jkm151030_640b
October Greenville County SC
Blue Wall Preserve
Leaves usually pubescent, at least beneath, per Vascular Flora of the Carolinas (Radford, Ahles, & Bell, 1968).
)
JK Marlow jkm151030_641
October Greenville County SC
Blue Wall Preserve
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (4/24/22):
Silphium reniforme
FAMILY
Asteraceae
SYNONYMOUS WITH
PLANTS NATIONAL DATABASE:
Silphium compositum var. reniforme
FAMILY
Asteraceae
INCLUDED WITHIN
Flora of North America north of Mexico, vol. 19-20-21
Silphium compositum
SYNONYMOUS WITH
VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 179-54-002b:
Silphium compositum var. reniforme
FAMILY
Asteraceae
SYNONYMOUS WITH
Manual of the Southeastern Flora (Small, 1933, 1938)
Silphium reniforme
2113
Forb
Perennial
Habitat: Dry forests, woodlands, roadsides, per Weakley's Flora
Native to the Carolinas & Georgia
Uncommon (rare in GA)
CLICK HERE to see a map, notes, and images from Weakley's Flora of the Southeastern US.
LEAVES:
Simple
Alternate
FLOWER:
Summer/Fall
Rays: Yellow
Disc: Yellow
Flower heads with 6-12 ray flowers, notched at apex
Inferior ovary
Disc flowers functionally staminate/ Ray flowers pistillate & fertile
FRUIT:
Summer/Fall
Achene
TO LEARN MORE about this plant, look it up in a good book!
- Forest Plants of the Southeast and Their Wildlife Uses (Miller & Miller, 2005) p172?
- Wildflowers of Tennessee (Carman, 2005) p326?
- Wildflowers of Tennessee, the Ohio Valley, and the Southern Appalachians (Horn, Cathcart, Hemmerly, & Duhl, 2005) p377?
If a search such as "Carex leptalea var. leptalea" doesn't deliver the results you want, try "Carex leptalea".
Or, to minimize chances of a misspelling, try just "Carex le".
Less is more: If "pencil flower" doesn't deliver the results you want, try "pencil".