Ash Dieback in UK

This is not P. ramorum, but a new strain of an invasive fungal disease in the UK that is having a serious impact on a native tree species.

Ash dieback: Government faces possible legal action
A nursery forced to destroy 50,000 ash trees after a fungal disease was found is considering taking legal action against the government for failing to block imports sooner.

Read the article on BBC News

Nursery update

To date in 2012, the US has had 32 P. ramorum-positive nurseries in seven states (CA-6; OR-11; WA-10; NC-1; ME-1; NY-2; PA-1) as well as 4 positive residential/ landscape detections (CA, OR, WA, ME). Positive plants included: Rhododendron (51%); Camellia (13%); Viburnum (11%); Pieris (7%); Kalmia (3%); Gaultheria (4%); Loropetalum (3%); Magnolia (3%); Hamamelis (2%); Cornus (1%); Prunus (1%); and Trachelospermum (1%). Seventeen of the positive nurseries are interstate shippers (CA-2; OR-7; WA-7; NY-1) and 15 are retail facilities (CA-4; OR-4; WA-3; NC-1; ME-1; NY-1; PA-1). Collection ponds were positive at 2 retail nurseries (WA, NY) and 3 that ship interstate (2-WA, 1-NY). Soil was positive at 1 retail nursery (CA), 2 interstate shipping nurseries (CA, OR), and 1 landscape site (WA). Ten interstate trace-forward investigations were conducted this year: three with potentially infected plants shipped to 24-30 states and seven with potentially infected plants shipped to 1 to 3 states. As a result, P. ramorum was detected at retail nurseries in ME and PA that were shipped from OR, and from three residential/landscape sites in OR, WA, and ME that originated in WA. Confirmed Nursery and/or Residential Protocols are being implemented at all locations.

From September 2012 COMTF newsletter

Water treatment research at WSU

The Chastagner lab at Washington State University, Puyallup plans to develop a biofiltration testing facility and determine the effectiveness of several techniques for removing P. ramorum inoculum from water. Methods similar to those being used for remediating stormwater are being considered for removing pathogen inoculum from nursery runoff and will have the added advantage of removing pollutants. These methods will consist of biofilters using various organic substrates, constructed wetlands or rain gardens, and physical methods such as sand filtration or sedimentation. Pilot biofiltration systems will be installed at selected P. ramorum-positive nurseries in Washington and be part of a training program for nursery managers. A Best Management Practices workshop will also be held for nursery managers regarding the installation and maintenance of cost-effective biofiltration systems for removal of Phytophthora inoculum in water. Funding for the project has been made possible by the Farm Bill and the Washington State Department of Agriculture Nursery Research Program.

From Sept. 2012 COMTF newsletter

Questions? Comments? Email Marianne Elliott

Video - using steam to treat soils infested with P. ramorum

On youtube - an interview with Rick Bostock, UC Davis, on steam treatment of soils

http://www.youtube.com/watch?v=MQYrB4PNK4Q

New Article

The August 2012 IUFRO Pathology Newsletter featured the article “Communicating Forest Pathology Issues to a Broad Audience”.  The story discusses how forest diseases caused by Phytophthoras have become increasingly visible to the general public as trees within recreational areas have succumbed to disease.  Sudden Oak Death (California), kauri dieback (New Zealand), and P. cinnamomi (Australia) are cited as three examples of devastating disease involving Phytophthoras that have had good coordination among scientists and different levels of government, resulting in effective research programs and communications strategies being put in place to help understand each problem and raise public awareness in an attempt to reduce pathogen spread.

From August COMTF newsletter.

Read the rest of the newsletter to learn more about forest diseases worldwide.

Oregon nursery updates

To date this year, the Oregon Department of Agriculture (ODA) confirmed 11 P. ramorum-positive nurseries in Clackamas, Curry, Lane, Lincoln, Marion, Multnomah, Polk, Tillamook, and Washington Counties.  Infected plants have included Camellia japonica; C. japonica ‘Grand Prix’ and ‘Mrs. Tingley;’ Hamamelis virginiana; Kalmia latifolia; Pieris sp.; P. japonica; Rhododendron cultivars ‘Baden Baden,’ ‘Bessie Howell,’ ‘Black Sport,’ ‘Holden,’ and ‘Maximum Roseum;’ Rhododendron sp.; Viburnum sp.; V. davidii; and V. tinus.  The Confirmed Nursery Protocol is underway at all 11 nurseries.

The positive plants found in the Curry County nursery (now closed for business) were infected with the EU1 lineage.  No infected plants were found at the nursery during inspection last year; however, 13 infected plants were found this year.  This is the first report of the EU1 lineage in Curry County.  ODA has implemented a voluntary recall for all potentially infected plants sold from the nursery.  Follow-up inspections have been negative for the pathogen; ongoing monitoring is still underway.

P. ramorum was also detected at a private residence in Lane County (Oregon) based on trace-forward information received from USDA APHIS.  The pathogen was detected infecting Gaultheria shallon and G. procumbens plants that had been imported from Washington and were still in their containers.  The USDA Confirmed Residential Protocol has been implemented.  For more information, contact Nancy Osterbauer at nosterbauer@oda.state.or.us.

From August COMTF newsletter.

New P. ramorum area in Curry County

A new Phytophthora ramorum outbreak has been identified on the Rogue River-Siskiyou National Forest 10 miles east of Brookings, OR.  The site is ½ mile east of the current quarantine boundary; therefore, an emergency quarantine was put into effect, bringing Oregon’s Sudden Oak Death (SOD) quarantine area to 229 square miles.  The outbreak was found when two dead tanoaks were identified in the Wheeler Creek drainage near Chimney Camp during April aerial surveys conducted by the Oregon Department of Forestry and the USDA Forest Service.  Subsequent ground surveys in the area identified 16 trees that are culture-positive for P. ramorum.  A hiking trail close to the site has been closed to the public since early June while officials work to eradicate the infestation.  Approximately 50 acres are being treated.

From August COMTF newsletter.