Illinois Natural History Survey - University of Illinois

Silphium integrifolium
Rosin weed, SILPHIUM SPECIOSUM, ROSIN WEED, Wholeleaf rosinweed, Entire-leaf rosinweed
Taxonomy

Synonyms: Silphium integrifolium var. neglectum, Silphium integrifolium var. laeve, Silphium integrifolium var. integrifolium, Silphium integrifolium var. deamii, Silphium speciosum

Subspecific taxa:

Classification:

Other taxonomic & nomenclature sources: USDA Plants;  ITIS;  The Plant List;  IPNI

Images

   
View all images. View all at PhytoImages.
Species Distribution
If map does not appear refresh browser Refresh
Click map to view & download detailed occurrence records

More about map & occurrence records

County Map Legend
Absent:
Not known from county
Medium confidence:
Medium or unknown confidence;
often old records or unverifiable observations
Medium-high confidence:
Often observations by expert botanists
High confidence:
Often vouchered herbarium records
Planted / introduced:
Native species introduced outside historic range,
or only in planted locations within county (e.g., restorations)
Historic / extirpated:
Only historic records for the species; likely extirpated
(Note that this category is not yet functional)

North American distribution maps for this species: FLNA;  USDA Plants;  BONAP;  BISON

Collections, Observations & Flowering by Month [?]

J
0
F
0
M
0
A
0
M
0
J
0
J
0
A
0
S
0
O
0
N
0
D
0

Collections & Observations by Decade [?]

Species Status

Status/Listing: No Information

Notes:

Origin:

Species Description

General: Dicot-herb, perennial

Roots: adventitious, rhizomes

Shoots: opposite, basal leaf arrangment; simple leaf type; entire leaf margin; Pinnate leaf venation; oblong leaf shape

Inflorescence: panicle, corymb, head

Flowers: unisexual, monoecious; 5 merous; yellow; epigynous ovary position

Fruit: achene

Physiology: autotrophic

Reproduction: sexual

Ecology & Natural History

Habitat: Commonly with Andropocon gerordii and other Silphium species. Often survives severe degradation of prairies. Rocky, open woods. One collection - along Milwaukee railroad near Illinois Route 43.

ILPIN Notes: Plants with alternate leaves are suspected hybrids of S. integrifolium and S. astericus. Broad corymb, leaves scabrous on both surfaces - with a short woody rhizome - may also have creeping rhizomes. Achenes obovate, winged, with a deep, narrow apical sinus. Two varieties are recognized by some authors in Chicago area. This includes S. speciosum, or var. laeve. T. & G. Species introduced from the western states. Species is glaucous at least on stem; additionally the peduncles, involucral bracts, and lower leaf surface (except the midrib) are glabrous. Larger and broader bracts than S. integrifolium; with short woody rhizome; may also have creeping rhizomes.

Functional Relationships:

  • Pollinators:
  • Dispersal:
  • Mycorrhizae:
  • N2 fixation:

Human Relationships:

  • Edibility [?] :
  • Showy Flowers:

Wildlife and Livestock Information:

  • Food Value:
  • Cover Value:

Coefficient of Conservatism (C-value) [?] :

  • Entire State: 5
  • Chicago Area: 5

Post a Comment or Question About this Plant
Name

Email address (required)

Comment? Question? 300 word limit (required)




Enter the text code above (required)

Note: All submissions are moderated and only some are posted. Posted comments may be edited for length. An email address will not be posted, but it is required for communication with the site moderator. Comments focused outside of Illinois and neighboring states may be posted, but more attention will be given to Illinois centered information. Thanks for your interest.