Phytophthora ramorum management

[Jbear]

Hey guys,

 

Just wondering about your thoughts on control of Phytophthora ramorum in a woodland area and techniques on how to re-plant afterwards. Would a complete clear fell of the area be more beneficial than simply containing it in terms of ecological impact?

 

Thanks

 

Jim

[treeseer]

Diseases of Trees and Shrubs (sold by TCIA) comes from the same Cornell campus as Dr. Hudler. On pages 354-366, Dr. Sinclair describes many treatments for Phytphthora:

1. Fracturing subsoil to allow deep drainage, as without free water the disease cannot spread.

2. Amending soil to improve structure

3. Inoculating with microbes to outcompete or directly attack the pathogen.

4. Applying calcium fertilizers or soil amendment with gypsum. “…calcium calcium compounds interfere with sporangium formation and zoospore function and thus suppress infection."

5. Drenching with “Phytophthora-suppresive fungicides to limit damage."

6. Drenching with “…resistance-inducing chemicals such as potassium phosphate.”

7. Surgery to remove inoculum. “(Phytophthora sp.) derives nourishment from recently killed as well as living tissues, and it reproduces in the dead tissues."

8. Applying heat to kill pathogens and promote closure.

9. Injecting minerals or fungicides.

[Jarhead]

Organisations such as DEFRA enforce the slash and burn technique to be used on infected sites.

 

Is there a reason this is the only method that seems to be used? Does reduction in risk of spread outweigh the ecological impact on a woodland?

 

It seems to me that it's one of the newly introduced pathogens that will spread regardless of management techniques. These will just slow it down.

 

(If anyone knows a good piece of literature written about this I would be grateful)

[treeseer]

Olaf has published a "Sourcebook of the genus Phytophthora"(1978) 420 pp. Presently used in over 85 countries and is also co-author with Professor Don Erwin (University of California), of the book Phytophthora Diseases Worldwide published by APS Press (1996). 592 pp. 2nd printing 2005.

 

He spoke at one of the TEP sessions I believe. About

 

I thought nukeandfell was US habit, and the UK would have a broader perspective.

[Jarhead]

Thank you for the references.

 

The go-ahead is usually complete removal of Rhododendron in likely or already infected sites and removal of infected trees.

 

The woodland near me however had a large chunk fully removed. (no re-planting with heavy bracken growth )