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Sudden Oak Death Agriculture

Events


Events

Upcoming events

No events are scheduled at this time.


Past events

June 28-30 Preventing the spread of Phytophthora ramorum via water. Allmendinger Center, WSU Puyallup

July 29 2010

Stream monitoring pilot study meeting and lunch. We will discuss the results from 2010 and plan for the 2011 monitoring. Email Marianne if you plan to attend.

10 AM – 2 PM Allmendinger Center, WSU Puyallup

January 27, 2010

Planning meeting for stream monitoring pilot study

August 27, 2009

Establishing an Enhanced Monitoring Program for Phytophthora Pathogens in Western Washington Streams At this meeting we will determine the level of interest and plan a program of stream monitoring for Phytophthora ramorum and other Phytophthoras in Western Washington. This may also serve as a template for monitoring other plant pathogens that can be moved in water.

8:30 am – 3:00 pm Allmendinger Center, WSU Puyallup


2003 Sudden Oak Death Meeting at WSU Puyallup (Video archive)

Presentations

Download presentations from past events here for use in your own training sessions:

Detecting and Managing SOD in Nurseries and Landscapes – Presented at WSU Snohomish County Extension workshop on tree diseases Oct. 15, 2009 (pdf, 4 mb)
Sudden Oak Death, Madrone Canker, and Systemic Acquired Resistance – Presented at Target Specialty Products Fall Arbor Symposium, Tualatin, OR Oct. 14, 2009 (pdf, 5.6 Mb)
Sudden Oak Death in Washington State – Presented at the Seattle Pesticide Recertification Seminar Oct 2008 (Powerpoint presentation 5.5 Mb)
P. ramorum education for Master Gardeners (Powerpoint presentation, ~7 Mb)


What kind of education or research seminars would you like to see? Email suggestions for future events to Marianne Elliott (melliott2@wsu.edu).
Contact: Gary Chastagner, 253-445-4528 | WSU Puyallup Research & Extension Center, 2606 West Pioneer, Puyallup, WA, 98371-4998 USA Last updated January 2, 2013

Publications


Publications

Brochures

Drainage water
Drainage water

Posters

 

Contact: Gary Chastagner, 253-445-4528 | WSU Puyallup Research & Extension Center, 2606 West Pioneer, Puyallup, WA, 98371-4998 USA Last updated January 2, 2013

Foliar Symptoms-Photos


Foliar Symptoms Caused by Phytophthora ramorum

Leaf Blight examples
Leaf Blight examples

Contact: Gary Chastagner, 253-445-4528 | WSU Puyallup Research & Extension Center, 2606 West Pioneer, Puyallup, WA, 98371-4998 USA
Last updated January 2, 2013

Questions to determine the likelihood of P. ramorum infection


Questions to determine the need to submit a homeowner sample in Washington State

1) The plant displays leaf blight, defoliation, or stem die back symptoms similar to those shown in the photographs.
a. Yes- go to 2
b. No- Sample can be discarded
2) What plant is affected?
a. The plant is a camellia, rhododendron, pieris, kalmia, viburnum, or lilac purchased since 2002- Submit sample
b. The plant is growing next to a camellia, rhododendron, pieris, kalmia, viburnum, or lilac purchased since 2002- go to 3
c. None of the above- unlikely P. ramorum. Sample can be discarded.
3) Is the plant a known host of Phytophthora ramorum?
b. Sample can be discarded
 

Contact: Gary Chastagner, 253-445-4528 | WSU Puyallup Research & Extension Center, 2606 West Pioneer, Puyallup, WA, 98371-4998 USA
Last updated January 2, 2013

Plants photo gallery


Plants photo gallery

Confirm that nursery stock is purchased from a licensed, certified shipping nursery or that material is propagated on-site.

USDA APHIS
USDA APHIS
Inspect all incoming nursery stock (buy-ins, transfers, and returns) prior to introduction into the nursery facility. Avoid mixing incoming plants with existing stock until plants have been examined for disease symptoms by trained personnel. Plants to be inspected
For buy-ins of high risk plants, suspend the use of Phytophthora specific fungicides on 10% or 100 plants, whichever is smaller, for a 2 month period. This will show if fungicides used by the seller were suppressing symptoms prior to purchase.High risk plants for P. ramorum include rhododendron, camellia, pieris, kalmia, and viburnum. High Risk Phytophthora Plants
Arrange plants to minimize damage caused by P. ramorum should it enter the nursery.Avoid mixing high-risk genera (Rhododendron, Camellia, and Viburnum) with other host and non-host plants. It is recommended to keep a 2 meter break between high risk plants and other material. IMG_5475_2
Manage weeds on the nursery site as they could serve as alternate hosts for diseases or be potential reservoirs for disease organisms. weeds in gravel
 Back to Managing Phytophthora diseases in the nursery

Water management photos


Water management photo gallery

Phytophthora can spread from cull piles where diseased plants are disposed of, especially if the site is muddy with standing water. Spores can be tracked throughout the nursery on vehicle tires and workers shoes.Ensure that runoff from cull piles is directed away from areas such as roads, growing beds, soil components and mixing areas, and especially from areas containing high-risk host plants to prevent contamination by spores. Cull Pile
Avoid overhead irrigation. If you use overhead irrigation, ensure that leaf wetness of 12 hr or more is minimized. Irrigate in the morning to allow leaves to dry as soon as possible. smConifer Inoculum Production Study 035
Drip irrigation saves water and reduces the chances of infection. However, if the soil or media stays wet and in contact with the plant, infection may result.

Drip irrigation
Drip irrigation
Dirt roads are prone to flooding in the wet climate of the Pacific Northwest.Standing water in roadways is a good environment for Phytophthora and Pythium, whose spores can be spread on vehicle tires. Managing Water
To prevent flooded areas where waterborne diseases can accumulate, a level, graveled road is the best option. Level Graded Road
Avoid letting water accumulate under or around blocks of containerized nursery stock. Allowing plants to stand in water increases the chances for Phytophthora root infection. Plants in standing water
These plants are set out on a sloped area, allowing water to run off rather than accumulate.However, water should be diverted from hillsides populated with P. ramorum host plants since spores move in water. Place these plants at the bottom rather than the top of the slope.

sloped area
Plants on a sloped area
Disease can be spread throughout a nursery in recycled irrigation water.Irrigation water from any source other than well or municipal water should be monitored for P. ramorum if the pathogen is detected in or near the nursery grounds.

Dangers of recycled irrigation water
Dangers of recycled irrigation water
Retention ponds should be tested periodically for presence of Phytophthora and Pythium species. It is a good idea to monitor for Phytophthora species in general to reduce damage caused by these diseases.

Retention Pond Testing
Retention Ponds should be tested regularly
Water in ponds can be treated with chemicals, such as sodium hypochlorite, to eliminate disease organisms. Water Treatment
 Back to Managing Phytophthora diseases in the nursery

 

 

Contact: Gary Chastagner, 253-445-4528 | WSU Puyallup Research & Extension Center, 2606 West Pioneer, Puyallup, WA, 98371-4998 USA
Last updated January 2, 2013

Containers


Containers

Disease can be transmitted in a nursery via used containers, which may harbor spores in potting media and plant debris. It is important to use clean containers for high risk host material, such as Rhododendron, Camellia, and Viburnum, to prevent infection of new plants.Containers on mat

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Incoming Plant Material


Incoming Plant Material

Keep diseases out of your nursery by purchasing clean nursery stock from a trusted supplier. Monitoring incoming plant material is especially important in Washington since most is grown out of state.

Click here to see photos of situations involving plant material in nurseries.

Check plant material for disease symptoms before integrating it into the rest of the nursery stock using this guide to symptoms of Phytophthora ramorum and look-alikes on important PNW host plants.

High risk hosts in Washington are Rhododendron, Camellia, Viburnum, Pieris, and Kalmia species. Recently Vaccinium and Gaultheria spp. have been found with P. ramorum. These hosts are sold and planted in large quantities and have been connected to outbreaks of P. ramorum.

If you suspect P. ramorum on plant material, isolate it from other host plants. This key will help you determine the likelihood of P. ramorum infection. You can submit a sample to the WSU plant clinic for analysis.

Symptom ID and Scouting -Presentation from the Best Management Practices workshops in 2014

Click here to view the most recent APHIS list of regulated and associated hosts for P. ramorum.

Lists of certified shipping nurseries for the Pacific Northwest:

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Sanitation


Sanitation

Many Phytophthora diseases, including P. ramorum, can survive and be transmitted in soil, potting media, and leaf litter. Good sanitation is important in reducing the amount of disease in the soil. Once the soil becomes infested with Phytophthora, it is very difficult to eradicate.

Photos – Management of soil and potting media, as well as sanitation techniques.

Sanitation for Nurseries -Presentation from the Best Management Practices workshops in 2014

USDA-APHIS approved methods for treatment and disinfection in nurseries (Appendix 8, Confirmed Nursery Protocol 2007)

Biosecurity measures for nurseries (Appendix 9, Confirmed Nursery Protocol 2007)

Articles

Dart, N.L., Chastagner, G.A., Rugarber, E.F., and K. L. Riley. 2007. Recovery Frequency of Phytophthora ramorum and Other Phytophthora spp. in the Soil Profile of Ornamental Retail Nurseries. Plant Disease 91: 1419-1422

Shishkoff, N. 2007. Persistence of Phytophthora ramorum in soil mix and roots of nursery ornamentals. Plant Disease 91: 1245-1249.

Tjosvold, S. A., D. L. Chambers, E. J. Fichtner, S. T. Koike, S. R. Mori. 2009. Disease Risk of Potting Media Infested with Phytophthora ramorum Under Nursery Conditions. Plant Disease 93:4, 371-376

Steam boilers and soil steam sterilization systems. MSD AG (Möschle-Seifert-Dämpftechnik).

Steam Treating for Weed Control. Whitney Ridout, American Nurseryman 2012

Using heat to eradicate soil-borne plant pathogens from nursery potting media (“soil sterilization”). Elizabeth Bernhardt and Ted Swiecki, Phytosphere Research

Soil environmental factors and their relation to avocado root rot by John A. Menge and Lawrence J. Marais, Citrus Research Board

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Water


Water Management

Since Phytophthora diseases are waterborne, good water management practices are key in preventing plant losses.

Water management photos  – Examples of water management situations in nurseries in the Pacific Northwest.

Water Management for Nurseries -Presentation from the Best Management Practices workshops in 2014

Water Sampling Protocol (Appendix 7, Confirmed Nursery Protocol 2007)

The Water Education Alliance for Horticulture at the University of Florida has a comprehensive website on water management, mainly chemical and other treatments for water.

 Irrigation Pathogens and Water Quality – Learn how to recycle water without recycling pathogens at this Virginia Tech site.

A Short Introduction to Water Recycling for Plant Nurseries – this presentation provides a good summary of water treatments for nurseries, to prevent disease spread and reduce pollutant runoff.

Facts and Myths About Irrigation Water An overview of irrigation water treatments and uses in nurseries.

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