| diffuse knapweed | USDA PLANTS Symbol: CEDI3 U.S. Nativity: Exotic Habit: Forbs/Herbs |
| Centaurea diffusa Lam. |
Jump to: Resources | Images | Distribution Maps | Sources
|
Taxonomic Rank: Magnoliopsida: Asterales: Asteraceae |
|
| Synonym(s): white knapweed | |
| Native Range: Temp. Asia, Europe (GRIN); | |
Diffuse knapweed is an annual, biennial, or short-lived perennial that is 8-40 in. (20-101.6 cm) tall. The basal leaves are lobed and stalked. The leaves become sessile, smaller, and less divided as they move up the stem. Flowering occurs from July to September, when white flowers develop in urn-shaped heads, in clusters, at the ends of the branches. The heads are subtended by leathery bracts. The lower and middle bracts have brown margins with spreading spines at the tips. Diffuse knapweed is native to southern Europe and north central Ukraine and prefers well-drained soils, roadsides, gravel pits, pastures and trails. |
|
Identification, Biology, Control and Management Resources
|
| Selected Images from Invasive.org | View All Images at Invasive.org |
 Plant(s); Sara Rosenthal, USDA Agricultural Research Service, Bugwood.org Additional Resolutions & Image Usage |
 Plant(s); Cindy Roche, , Bugwood.org Additional Resolutions & Image Usage |
 Flower(s); Steve Dewey, Utah State University, Bugwood.org Additional Resolutions & Image Usage |
 Flower(s); Steve Dewey, Utah State University, Bugwood.org Additional Resolutions & Image Usage |
 Flower(s); USDA APHIS PPQ Archive, USDA APHIS PPQ, Bugwood.org Additional Resolutions & Image Usage |
 Flower(s); Cindy Roche, , Bugwood.org Additional Resolutions & Image Usage |
 Flower(s); Close-up view of a flower head and flower bud of diffuse knapweed (Centaurea diffusa), showing the spiny bracts. L.L. Berry, , Bugwood.org Additional Resolutions & Image Usage |
 Seedling(s); Joseph M. DiTomaso, University of California - Davis, Bugwood.org Additional Resolutions & Image Usage |
 Plant(s); Steve Dewey, Utah State University, Bugwood.org Additional Resolutions & Image Usage |
| EDDMapS Distribution: This map is incomplete and is based only on current site and county level reports made by experts and records obtained from USDA Plants Database. For more information, visit www.eddmaps.org Alternative content
|
 State(s) Where Reported invasive. Based on state level agency and organization lists of invasive plants from WeedUS database. Alternative content
|
