Whorled Rosinweed

Scientific Name:   Silphium trifoliatum


In contrast to both False Sunflower and true sunflowers, only the ray florets of Silphium species produce seed, while their disk florets are seedless. Aster family (flower heads composed of multiple florets, often disk flowers or both disk and ray flowers).

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Whorled Rosinweed


Genus species: Silphium trifoliatum
Common Name: Whorled Rosinweed
Family Name: Asteraceae  
Flowers of two basic types: 1) disk florets with tubular corollas, and 2) ray florets with ligulate corollas. Heads are composed of exclusively one type or the other (discoid or ligulate), or typically with disk florets in the center and ray florets around the perimeter; fruit an achene (or cypsela).
Seed Type Angiosperm
Origin:  
Native: native to North America.
Non-native: not native to North America.
Introduced Native: native to North
America, but not Rowe Woods.
* Definitions based on the USDA
terminology
Native
Category:Wildflower
Flower Color:Yellow
Identified by:M. Becus
Months in Bloom  
The highlighted month(s) in this chart indicates the month(s) the plant has been observed blooming.
Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec

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