Interview with P. ramorum

The Don’t Move Firewood campaign has posted an “Interview with Sudden Oak Death Pathogen” to its website at http://www.dontmovefirewood.org/videos/interview-sudden-oak-death-pathogen.html.  In the humorous video, Sudden Oak Death and a talk show host have an informative “talk” about what plants are affected, how to prevent the spread, and more. The video was developed by the Don’t Move Firewood campaign, along with assistance from the COMTF and funding from the USDA FS Pacific Southwest Research Station.

From the December COMTF newsletter

Two treatments for P. ramorum infested nursery soil

Research at the National Ornamental Research Site at Dominican University of California (NORS-DUC) has provided two Green technology P. ramorum soil remediation deliverables that have been approved by the USDA Animal and Plant Health Inspection Service on a case by case basis for use in destroying P. ramorum in the soil substrate at contaminated nurseries.  Both technologies (steaming and the use of a biological control agent) have been successfully tested at a contaminated retail nursery and a contaminated wholesale nursery (ships interstate) in CA.  Follow-up sampling for the pathogen at both nurseries was negative, allowing each site to be released from the P. ramorum federal quarantine.

Technology transfer of these NORS-DUC successes to a wider national nursery audience is underway in a proposed multi-state Farm Bill proposal spearheaded by the Oregon Department of Agriculture, Washington State Department of Agriculture, WA State University and CA Department of Food and Agriculture.

From the December COMTF newsletter

Research - it's kid stuff

A citizen science project involving middle school students:

Bias in ecology and climate studies? How leaves shrink as they dry out is often overlooked

These kinds of projects get the public involved and provide them with a better understanding of the issues, in our case, surrounding SOD and P. ramorum.

UC: Buying local firewood helps prevent spread of pests

There is plenty of firewood left from last years ice storm in western WA. Remember to burn it where you buy it.

DAVIS, Calif. - University farm advisors here are urging consumers to use local firewood this winter to avoid moving pests and plant diseases into and around California.

Article from Capital Press

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.

Washington nursery update

Washington has had 10 confirmed positive nurseries to date in 2012, the most in a single year since 2006. Counties with detections include King, Pierce, Thurston, Lewis, Clark, Clallam, and Skagit. Eight of the nurseries are repeat positives and six are certified interstate host shippers, three of which have shipped host and associated host plant material in the past six months. Positive plants have included Rhododendron, Viburnum, Camellia, Magnolia, two Pieris, and one Gaultheria. With most of the positive nurseries in Washington catering to the landscape trade, and the housing industry slow, at least four of the 10 sites have had some of the currently positive plants in the nursery yard for over a year. It is unknown how long they have been infected on site.

From the July 2012 COMTF newsletter

Stream monitoring update

A stream in western Washington and one in northern Georgia have been found P. ramorum positive for the first time as a result of the National Early Detection Survey of Forests, bringing the total number of positives to date for this year to 14. Both new stream positives are in urban areas with current or formerly positive nurseries in the vicinity. Stream baiting will continue in an effort to identify the inoculum sources. In addition, the eight eastern sites in MS, AL, GA, FL, and NC found positive in the past have been confirmed positive again in 2012.

from the July COMTF newsletter

Fourth genetic lineage of Phytophthora ramorum pathogen identified

The increasing intensity of the P. ramorum outbreaks in the UK led researchers to analyze samples from the new findings further, which resulted in the discovery of a fourth genetically distinct lineage of the pathogen.
Announcing this at the Fifth Sudden Oak Death Symposium in California recently, Clive Brasier, an emeritus professor with the Forestry Commission's Forest Research agency, said he believed, based on genetic analysis, that the previously unknown European Type 2 (EU2) lineage had been recently introduced into south-west Scotland and Northern Ireland.

Read the full article here

Natural stem infection of Lawson cypress (Chamaecyparis lawsoniana) caused by Phytophthora ramorum

This is the first report of C. lawsoniana as a natural host of P. ramorum. In November 2010, P. ramorum was isolated from a 4 m long by 60 cm wide aerial phloem lesion on another mature C. lawsoniana in a park near Clydebank, Scotland. There was heavy resinosis at the top of the lesion. Adjacent rhododendrons were also infected with P. ramorum. Ten other large C. lawsoniana at the Clydebank site had dieback and aerial or collar lesions caused by the recently introduced Phytophthora species, P. lateralis (SA Green, CM Brasier and JF Webber, unpublished). Such an overlap between P. ramorum and P. lateralis on C. lawsoniana on the same site is likely to lead to direct physical contact between the two species. Since they are closely related phylogenetically and produce similar fruiting structures (e.g. Brasier et al., 2010), such novel contact could result in their hybridisation (Brasier, 2000). This possibility is under investigation.

Read the full article here.

Webinar - Scheduling Lawn and Garden Watering on your Smartphone or Web Browser

Learn how to plan your watering to eliminate flooding and Phytophthora problems. Attend this free webinar:

“Scheduling Lawn and Garden Watering on your Smartphone or Web Browser”

When do I turn the water on?  How long do I leave it on?  These are simple questions with difficult answers.  This webinar will describe how to use a new irrigation scheduling tool that runs equally well on a Smartphone or any web browser to greatly simplify making these decisions in a way that will result in green lawns and healthy gardens, save you work, and most importantly save on your water bill!

Tuesday May 29^th at 7:00 PM go to breeze.wsu.edu/rain and log in as a guest. Dr. Troy Peters, WSU Extension Irrigation Specialist will guide viewers  through the process and answer questions.

History is Key Factor in Plant Disease Virulence

A study of P. ramorum isolated from different hosts shows changes in virulence:

"The virulence of plant-borne diseases depends on not just the particular strain of a pathogen, but on where the pathogen has been before landing in its host, according to new research results.
Scientists from the University of California System and the U.S. Department of Agriculture's Agricultural Research Service (USDA ARS) published the results today in the journal PLoS ONE.
The study demonstrates that the pattern of gene regulation--how a cell determines which genes it will encode into its structure and how it will encode them--rather than gene make-up alone affects how aggressively a microbe will behave in a plant host.
The pattern of gene regulation is formed by past environments, or by an original host plant from which the pathogen is transmitted."

Read more in the press release from the National Science Foundation

Forest Insects and Diseases Arrive in US Via Imported Plants

ScienceDaily (Apr. 9, 2012) — The trade in live plants from around the world has become a major industry in the United States, with new imports now valued at more than $500 billion annually. According to a study conducted by researchers at UC Santa Barbara's National Center for Ecological Analysis and Synthesis, however, what has proved to be a boon for the economy has also been shown to have devastating effects on the environment.

(read more)

New website about invasives

Learn about emerging invasive species (including P. ramorum) in the US at the USDA Hungry Pests site:

http://www.hungrypests.com/index.php

Increased risk of damage from Phytophthora diseases under climate change

Sudden Oak Death and other Phytophthora tree diseases are predicted to be the most damaging of all tree diseases if climate change makes conditions in Western North America wetter and warmer.  This finding is one of the conclusions from "A Risk Assessment of Climate Change and the Impact of Forest Diseases on Forest Ecosystems in the Western United States and Canada," by John Kliejunas.  Drawing on a large body of published research, the report details the effects of eight forest diseases under two climate-change scenarios – warmer and drier conditions, and warmer and wetter conditions. The likelihood and consequences of increased damage to forests from each disease as a result of climate change were analyzed and assigned a risk value of high, moderate, or low.  The risk value is based on available biological information and subjective judgment.  Free copies of the report are available via download or by mail at http://www.fs.fed.us/psw/publications/documents/psw_gtr236/.  Funded by the USDA Forest Service's Western Wildland Environmental Threat Assessment Center and the Pacific Southwest Research Station, the risk assessment was conducted as part of the Climate Change and Western Forest Diseases initiative.
Kliejunas, J.T. 2011. A risk assessment of climate change and the impact of forest diseases on forest ecosystems in the Western United States and Canada. Gen. Tech. Rep. PSW-GTR-236. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 70 p.

From COMTF April Report

Not even celebrities are exempt

Linda McCartney memorial wood is destroyed by disease

When hundreds of trees were planted in remembrance of Linda McCartney, it was hoped that they would grow to be a living and lasting memorial to the first wife of Sir Paul McCartney.

Now, however, all the larch trees in Linda’s Wood have had to be chopped down because of a deadly disease sweeping the country.

The trees were the victim of Phytophthora ramorum, or sudden oak death, which has jumped species and is infecting other trees including larch and the Douglas fir.

Read more here - The Telegraph

 

Washington stream monitoring updates

The Washington State Department of Agriculture will no longer be monitoring waterways in the state as of 2012. Nursery-level monitoring required under the Confirmed Nursery Protocol will continue. Stream baiting efforts are still be conducted by the Washington Department of Natural Resources (DNR); however, with 2012 sampling having commenced in late January in 5 counties and 10 watercourses. The first (of likely six) round of samples has been retrieved for analysis. In addition to leaf baiting, DNR will be working with the USDA Forest Service on “Bottle of Bait” protocols to assay each of the streams for P. ramorum. More baiting stations will likely be added to the survey over the course of the sampling period if P. ramorum is detected at any of the sites.

from the March COMTF newsletter

Boxwood blight - a new disease

Boxwood blight, a fungal plant disease new to North America, has been detected in Oregon for the first time, prompting state officials to take measures to eradicate it. However, unlike the pathogen that causes sudden oak death, the newly-reported disease is no threat to the state’s environment and only affects boxwoods, a plant species that is not native to Oregon.

Boxwood blight, Cylindrocladium buxicola, has now been found in eight states and a Canadian province. It has previously invaded Europe and New Zealand. Boxwoods are commonly grown and sold by nurseries. The Oregon Department of Agriculture discovered boxwood blight disease at a Washington County nursery in December. ODA is working with the nursery to destroy all the infected blocks by bagging and burying the plants. The nursery is also voluntarily taking other actions to get rid of the disease.

 Read more at naturalresourcereport.com

New website shares information about deadly tree pathogens

Sudden oak death, Port-Orford-cedar root disease and other deadly tree diseases caused by Phytophthora species (pronounced fy-TOF-ther-uhs) are threatening forest ecosystems worldwide. These microorganisms, which are related to algae and diatoms, spend part of their life cycle in soil or water but once they infect trees, they can kill them. A new web site, developed jointly by the USDA Forest Service Pacific Southwest Research Station and Oregon State University, hopes to put knowledge and resources in the hands of scientists and land managers as they look for ways to fight these deadly diseases.

website: www.forestphytophthoras.org/

Read the rest of the article at www.physorg.com 

Bloedel Reserve horticulturists trained to detect serious pests and pathogens

Bloedel Reserve has joined the Sentinel Plant Network (SPN), a partnership of the American Public Gardens Association (APGA) and the National Plant Diagnostic Network (NPDN), an organization funded by the U.S. Department of Agriculture. The SPN is focused on engaging public garden professionals, volunteers, and visitors in the early detection of high-consequence plant pests and pathogens.

Full article at KPBJ.com