Information

Agent

Puccinia jaceae var. diffusae Savile

Class: Pucciniomycetes
Order: Pucciniales
Family:

Agent Name References:
- Coombs, E.M. 1997. Biological control of weeds in Oregon. Annual Report. Project summaries 1996. Oregon Department of Agriculture, Noxious Weed Control Program, Salem, Oregon, USA. 33 pp.
- Joley, D.B., D.M. Woods, and C.E. Turner. 1996. Biological control of diffuse knapweed, Centaurea diffusa. In L.G. Bezark, Ed. Biological Control Program 1995 Annual Summary. California Department of Food and Agriculture, Division of Plant Industry, Sacramento, California. pp. 24.
- Kirk, P.M., P.F. Cannon, D.W. Minter, and J.A. Stalpers, Eds. 2008. Dictionary of the Fungi, 10th edition. CABI Publishing, U.K. 784 pp.

Weed

Centaurea diffusa Lam.

Family: Asteraceae
Common Name: diffuse knapweed

Origin: Eurasia

Weed Name References:
- Seastedt, T.R., D.G. Knochel, M. Garmoe, and S.A. Shosky. 2007. Interactions and effects of multiple biological control insects on diffuse and spotted knapweed in the Front Range of Colorado. Biological Control 42: 345-354.
- Story, J.M., G.L. Piper, and E.M. Coombs. 2004. Knapweeds. In E.M. Coombs, J.K. Clark, G.L. Piper, and A.F. Cofrancesco, Eds. Biological Control of Invasive Plants in the United States. Oregon State University Press, Corvallis, Oregon. pp. 196-232.

Weed Common Name References:
- Seastedt, T.R., D.G. Knochel, M. Garmoe, and S.A. Shosky. 2007. Interactions and effects of multiple biological control insects on diffuse and spotted knapweed in the Front Range of Colorado. Biological Control 42: 345-354.
- Story, J.M., G.L. Piper, and E.M. Coombs. 2004. Knapweeds. In E.M. Coombs, J.K. Clark, G.L. Piper, and A.F. Cofrancesco, Eds. Biological Control of Invasive Plants in the United States. Oregon State University Press, Corvallis, Oregon. pp. 196-232.

Weed Origin References:
- Seastedt, T.R., D.G. Knochel, M. Garmoe, and S.A. Shosky. 2007. Interactions and effects of multiple biological control insects on diffuse and spotted knapweed in the Front Range of Colorado. Biological Control 42: 345-354.
- Story, J.M., G.L. Piper, and E.M. Coombs. 2004. Knapweeds. In E.M. Coombs, J.K. Clark, G.L. Piper, and A.F. Cofrancesco, Eds. Biological Control of Invasive Plants in the United States. Oregon State University Press, Corvallis, Oregon. pp. 196-232.

Release and Source Information

List: 3 - Previously Used or Potential Agents Found in Exotic Ranges where their Deliberate Release is not Recorded

Year First Recorded: 1996
Region: North America
Country Found: United States of America
Subregion of Country: CA, OR
Subregion specific:

Source: Ex. Unknown via Canada
Deliberate Redistribution?: No
Year Redistributed:
Country: United States of America
Subregion of Country:
Subregion specific:

Release History: First recorded in CA OR 1996

Release Notes: Spread to USA via Canada, though original mode of entry into Canada unknown.

Source Information References:
- Coombs, E.M. 1997. Biological control of weeds in Oregon. Annual Report. Project summaries 1996. Oregon Department of Agriculture, Noxious Weed Control Program, Salem, Oregon, USA. 33 pp.
- Joley, D.B., D.M. Woods, and C.E. Turner. 1996. Biological control of diffuse knapweed, Centaurea diffusa. In L.G. Bezark, Ed. Biological Control Program 1995 Annual Summary. California Department of Food and Agriculture, Division of Plant Industry, Sacramento, California. pp. 24.
- Woods, D. and V. Popescu. 2009. Diffuse knapweed biological control in California: 1976-2008. In D.M. Woods, Ed. Biological Control Program 2008 Annual Summary. California Department of Food and Agriculture, Plant Health and Pest Prevention Services, Sacramento, California. pp. 43-46.

Original Host Species

Unknown

Establishment

Established: Yes
Established in Subregion of Country: CA, OR
Established in Subregion specific:

Establishment References:
- Coombs, E.M. 1997. Biological control of weeds in Oregon. Annual Report. Project summaries 1996. Oregon Department of Agriculture, Noxious Weed Control Program, Salem, Oregon, USA. 33 pp.
- Woods, D. and V. Popescu. 2009. Diffuse knapweed biological control in California: 1976-2008. In D.M. Woods, Ed. Biological Control Program 2008 Annual Summary. California Department of Food and Agriculture, Plant Health and Pest Prevention Services, Sacramento, California. pp. 43-46.

Abundance

Limited

Abundance References:
- Woods, D. and V. Popescu. 2009. Diffuse knapweed biological control in California: 1976-2008. In D.M. Woods, Ed. Biological Control Program 2008 Annual Summary. California Department of Food and Agriculture, Plant Health and Pest Prevention Services, Sacramento, California. pp. 43-46.

Agent Impact

Impact: Slight
Geographic Scale of impact: Localized
Impact Notes: Erratically infects from 1-62% of plants. Although most infected plants remain vigorous, some plants become severely infected and debilitated. Overall impact on population minor.

Impact References:
- Joley, D.B., D.M. Woods, and C.E. Turner. 1996. Biological control of diffuse knapweed, Centaurea diffusa. In L.G. Bezark, Ed. Biological Control Program 1995 Annual Summary. California Department of Food and Agriculture, Division of Plant Industry, Sacramento, California. pp. 24.
- Woods, D. and V. Popescu. 2009. Diffuse knapweed biological control in California: 1976-2008. In D.M. Woods, Ed. Biological Control Program 2008 Annual Summary. California Department of Food and Agriculture, Plant Health and Pest Prevention Services, Sacramento, California. pp. 43-46.

Limiting Factors

None

Other Attack

Were other species attacked?: No
Other Species Attacked Notes:

Research Organizations

Notes