Washington SOD Blog

Ho! Ho! Ho! - Toxic Christmas Trees?

2011-12-19T11:17:00.000-08:00

By Nate Seltenrich Courtesy of the Sierra Club

The Fraser fir is the ideal Christmas tree. Fragrant, strong-limbed and long-lasting when cut, it has found its way to the White House's Blue Room more than any other tree over the past 50 years. It is also a vector to the most destructive plant pathogen you've never heard of.

The shapely Fraser fir, a southern Appalachian native now farmed extensively in nurseries, is a common carrier - and victim - of Phytophthora cinnamomi, a deadly water mold wreaking havoc on ecosystems around the world. When infected Frasers are replanted, the disease gets an opportunity to spread to new farms and neighboring plant life.

Read the rest of the article in the Bandera County Courier

Buy Local, Buy Green: Holiday Greenery and Christmas Trees Should Come From Local Sources

2011-12-12T10:42:00.000-08:00

Informed purchases and adherence to state and federal regulations can prevent spread of forest pests

ARLINGTON, Va., Dec. 8, 2011 /PRNewswire-USNewswire/ -- Buying freshly-cut evergreen trees and greenery to decorate during the holiday season is a time-honored and favorite tradition. Unfortunately, harmful non-native insects and diseases can hitchhike on these trees and branches, starting new infestations in communities that were previously pest-free. This has become such a serious problem that federal and state governments now regulate the movement of Christmas trees, holiday wreaths, and related material. Buying locally cut trees from established vendors is better for the economy and the environment.

More than 450 non-native forest insects are now established in the United States. Federal and state regulations require certain conditions be met in order to move Christmas trees and wreaths out of areas quarantined due to pest infestations. These regulations are aimed at stopping the spread of gypsy moth, pine shoot beetle, sudden oak death (a tree disease), and other forest pests, which can be transported on holiday plant material.

Read more here:

Other items of interest

2011-12-12T10:39:00.000-08:00

Check out the December COMTF newsletter for these and other articles:

Patterns of Firewood and Forest Pests Brought to California in 2011, By Matthew Bokach, USDA Forest Service, Pacific Southwest Region Forest Health Protection

Alder Phytophthora: Native or Exotic? –Surprising New Findings

Canada/United States bilateral talks on P. ramorum policy

2011-12-12T10:35:00.000-08:00

The USDA Animal and Plant Health Inspection Service P. ramorum program manager and trade director for Canada attended a meeting hosted by CFIA (Canadian Food Inspection Agency) in Vancouver, British Columbia (BC) November 8 – 9, 2011 to discuss certification processes for shipments of P. ramorum host plants from Canada as well as other international commerce concerns. Regulatory survey data in addition to protocols and harmonization of regulations and host lists were reviewed, and visits were conducted to three propagation nurseries in BC under the Canadian Nursery Certification Institute (CNCI) Program. To date, P. ramorum detections in BC have only been in retail establishments and not in propagation nurseries which are the major shippers of host plants to the US.

From the December COMTF newsletter

The hidden cost of trade: Invasive species as a trade “externality”

2011-11-14T13:43:00.001-08:00

by Faith Campbell

Importation of invasive species is an intrinsic risk of international trade. As trade volumes rise, so do introductions. Preventing introductions is widely recognised as preferable to responding after they occur. Prevention measures require exporters and importers, as well as national governments and trade-promoting and managing entities such as the World Trade Organization, to implement steps aimed at ensuring that the exchange of goods is not accompanied by the dispersal of damaging organisms.

Nursery Pr positives

2011-10-20T13:11:00.000-07:00

The USDA APHIS P. ramorum Program 2011, 3rd Quarter Summary (posted at: http://www.aphis.usda.gov/plant_health/plant_pest_info/pram/downloads/updates/2011/3rdqtr-Sept2011.pdf) reported 25 nursery-related P. ramorum confirmations from January to September 30, 2011 in the following states: CA(12), OR (6), WA (5); SC (1); and CT (1 residential). Fourteen of the nurseries were interstate shippers and nine were retail. Positive plant detections were from the following plant species: Camellia (31%); Rhododendron (34%); Pieris (5%); Viburnum (5%); Magnolia (5%); Osmanthus (3%); Gaultheria (3%); Cinnamonum (3%); and 7 other species (11%).

From the COMTF October 2011 newsletter

Oak death creeps north

2011-10-20T13:07:00.000-07:00

Despite a multimillion-dollar control program, sudden oak deathhas spread six miles north of its quarantine zone in Curry County-- closer to Coos County.

UK government launches tree biosecurity plan

2011-10-20T13:00:00.000-07:00

The UK government has said that it will invest £7m to tackle tree diseases, amid fears that millions of trees could be lost unless urgent action is taken.

The Tree Health and Plant Biosecurity action plan was launched as scientists confirmed the arrival of a deadly disease in England among urban trees.

Phytophtora lateralis was recorded in Devon on a Lawson cypress, a popular species in parks and gardens.
Ministers hope the plan will tighten biosecurity measures and protect trees.

Read the entire article on BBC News.

Tree ailment could slam Oregon industries

2011-09-19T11:13:00.000-07:00

Researchers guess sudden oak death has cost Californialandowners several million dollars. The cost to Oregon could be fargreater.
While California's infestation is widespread, it mostly has hitsemi-urban areas, where it has damaged property values. The diseaseis only beginning to reach Northern California's timberindustry.

Read more: http://theworldlink.com/news/local/article_d95df55e-e0fc-11e0-8254-001cc4c002e0.html#ixzz1YQJR3fHl

This article by the same author has more background information and is worth reading:

Knock on wood
Thanks for sending this, Simon.

Investigating the Spread of Infectious Diseases With NSF, NIH, U.K. Funding

2011-09-19T11:09:00.000-07:00

How diseases are transmitted among humans, other animals, the environment is focus.

New research aimed at controlling the transmission of diseases among humans, other animals and the environment is being made possible by grants from a collaboration among U.S. and U.K. funding agencies.

By improving our understanding of the factors affecting disease transmission, the projects will help produce models to predict and control outbreaks.Funding is from the U.S. National Science Foundation (NSF) and U.S. National Institutes of Health (NIH) Ecology and Evolution of Infectious Disease (EEID) Program.It is also being provided by the U.K. Ecology of Infectious Diseases Initiative of the Biotechnology and Biological Sciences Research Council (BBSRC), and U.K. Economic and Social Research Council (ESRC).

Among the systems being studied is SOD:

Title: Interacting disturbances: leaf to landscape dynamics of emerging disease, fire and drought in California coastal forests
PI: David Rizzo, University of California - Davis

Summary: This research aims to better understand how the interaction of multiple factors like wildfire, drought, biodiversity and nutrient cycles can interact to regulate disease dynamics. Using long-term studies of sudden oak death, estimated to have killed millions of trees in the western U.S., scientists hope to gain new insights about how the emergence, persistence and spread of a pathogen is controlled by environmental disturbance.

Job posting

2011-09-12T11:58:00.001-07:00

This job is available to a qualified person with an interest in SOD:

A plant pathologist research position is available at NORS-DUC. Responsibilities include working collaboratively with NORS-DUC scientists, training undergraduates using NORS-DUC research as a teaching tool, developing and carrying out new projects based on NORS-DUC P. ramorum research priorities, and assisting with NORS-DUC-related grant writing. Review of applications will begin immediately and continue until the position filled. For more information, contact Sibdas Ghosh by email or at (415) 482-3583.

Current Research at NORS-DUC

2011-09-12T11:55:00.001-07:00

The mission of the National Ornamentals Research Site at Dominican University of California is to identify, prioritize, facilitate and conduct research related to pests and diseases of nursery stock while safeguarding plant health and the environment.

NORS-DUC is the first research site in the United States dedicated to the study of pests and diseases affecting the health of ornamental plants. The facility is funded by a grant from the 2008 Farm Bill, administered through the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) Plant Protection and Quarantine (PPQ) Center for Plant Health Science and Technology (CPHST).

Visit this link to see this years research projects at the National Ornamentals site at Dominican University of California (NORS-DUC).

http://www.dominican.edu/academics/hns/sciencemath/community-partnerships-and-initiatives/norsduc/research-at-nors-duc.html

Research article: Phytophthora ramorum in England and Wales: which environmental variables predict county disease incidence?

2011-09-12T11:51:00.001-07:00

Chadfield, V. and Pautasso, M. 2011. Phytophthora ramorum in England and Wales: which environmental variables predict county disease incidence? Forest Pathology. DOI: 10.1111/j.1439-0329.2011.00735.x.

Abstract: Phytophthora ramorum is the oomycete pathogen responsible for Sudden Oak Death on the West Coast of the USA and Sudden Larch Death in the British Isles. It also causes twig dieback and leaf blight on a series of ornamental hosts (e.g. Rhododendron, Viburnum, Pieris and Camellia) commonly grown in plant nurseries, traded by garden centers and cultivated in public and private gardens. The role of the plant trade in the dispersal of P. ramorum has been well documented, but there is a need for regional analyses of which environmental variables can predict disease expression in the trade and in the wild, so as to be able to better predict the further development of this worldwide plant health issue. In this study, we analyze data on the incidence of P. ramorum (2002–2009, thus before the reports in Japanese larch plantations) in counties in England and Wales as a function of environmental variables such as temperature and rainfall, controlling for confounding factors such as county area, human population and spatial autocorrelation. While P. ramorum county incidence in nurseries and retail centers was positively related to county area and human population density, county incidence in gardens and the wild did not show such correlations, declined significantly towards the East and was positively correlated with disease incidence in the trade. The latter finding, although not conclusively proving causation, suggests a role of the trade in the dispersal of this pathogen across English and Welsh landscapes. Combined together, P. ramorum county incidence in the trade and in the semi-natural environment increased with increasing precipitation and with declining latitude. This study shows the importance of environmental variables in shaping regional plant epidemics, but also yields results that are suggestive of a role of people in spreading plant diseases across entire countries.

P. ramorum in water workshop now on the web

2011-09-12T11:48:00.000-07:00

Preventing the spread of Phytophthora ramorum via water was the focus of a 2 ½ day workshop in Puyallup, WA, June 28-30, 2011. Attended by over 50 regulators, researchers, and industry representatives from the western and southeastern US, as well as Washington, DC, the workshop's mission was to coalesce research, management, and regulations for effective, economical, and environmentally acceptable ways of limiting P. ramorum spread via contaminated nursery water runoff. The group began the meeting with a visit to the site of a previously positive Gig Harbor retail nursery (where P. ramorum-infested water had escaped the nursery and infected riparian salal plants) to review treatments and mitigations implemented. Meeting presentations addressed the incidence and distribution of P. ramorum detections in waterways, water baiting techniques, risks and impacts for WA, and treatments to reduce the risk of spreading inoculum in water. Research and education/outreach needs were identified, with group exercises and discussion concentrated on nursery treatments as well as water management, monitoring, and notification of downstream users of contaminated water. More information on the workshop can be found at: http://www.puyallup.wsu.edu/ppo/sod/extension/workshops/Pr_water_jun_2011/index.html. The meeting was organized by Gary Chastagner, Washington State University, and Susan Frankel, USDA-Forest Service, Pacific Southwest Research Station, and sponsored by Washington State University and the California Oak Mortality Task Force.

Officials shift approach to sudden oak death

2011-09-12T11:44:00.000-07:00

Ten years after initiating a campaign to eradicate sudden oak death in Oregon forests, state officials are moving to Plan B."There is more to treat now than we have resources to treat," administrator of the Oregon Department of Agriculture's Plant Division Dan Hilburn said at a recent Oregon Board of Agriculture meeting. "The program has to change. There is no way we can treat this as an eradication program."The change in strategy -- from eradication to containment -- comes at a time when the disease is spreading rapidly and funding for controlling it is shrinking. Capital Press Posted: Tuesday, September 06, 2011 10:39 AM

Colourful allure of sudden oak death

2011-09-12T11:41:00.000-07:00

Sudden oak death doesn't sound pretty but snap it with the right camera, from the right angle, and it can look alluring.This forest in Cheshire, UK is one that's already known to suffer from sudden oak death, or Phytopthora ramorum. The firm APEM in Manchester used one of only two Leica RCD30 cameras in the world to photograph it from an aeroplane. With the ability to capture visible light and near-infrared, the 60 megapixel, £35,000 camera being tested as a method of diagnosing diseased trees.See it here: http://www.newscientist.com/blogs/shortsharpscience/2011/09/camera-reveals-tree-disease.html

UC Berkeley Research Links Tree Die-Offs to Climate Change

2011-08-08T11:34:00.000-07:00

An interesting idea:

Fungus-related plant diseases are wiping out forests across the world – and new research indicates a similar phenomenon emerged as a result of radical climate change some 250 million years ago. That in turn suggests that scourges such as sudden oak death, Dutch elm disease, and the collapse of eucalyptus stands in Australia could be linked to contemporary climate change.

Source: The Bay Citizen (http://s.tt/12YHN)

Agri-fos treatments to prevent SOD spread

2011-07-25T12:38:00.000-07:00

Scientists Battle Sudden Oak Death

A swath of uninfected forest on the Peninsula could hold the key to stemming the tree-killing disease

By John Upton

Source: The Bay Citizen (http://s.tt/12RB9)

On a hot summer day in 2008, a pair of plant disease researchers made an extraordinary discovery as they toured a hillside forest in San Mateo County: a stand of trees that had not been infected by the killer disease known as sudden oak death.

The healthy swath of forest, located on watershed lands owned by the San Francisco Public Utilities Commission, is now being used as a laboratory for the largest experiment ever conducted in the wild on a promising preventive treatment for this fast-spreading scourge.

P. ramorum found in Georgia stream

2011-07-25T12:30:00.000-07:00

Georgia trees threatened by disease
By April Reese Sorrow
University of Georgia

"In 2005, the Georgia Forestry Commission began monitoring selected Georgia waterways by floating rhododendron leaves in sample bags. They were looking for black spots on the leaves. They found them in 2009.

“We’ve detected the disease in a stream in Forsyth County,” she said. “But we can’t pin down the source. It was repeatedly detected since 2009, and all of the known affected areas have been fumigated. Stream water moves, so it is picking it up all over again from somewhere.”

Pathogens flushed into streams through runoff can lead experts to the source. They’re focusing on streams located in urban areas and around nurseries"

Read the whole article here

USDA funding for P. ramorum related projects

2011-07-11T12:13:00.000-07:00

The USDA is allocating $50 million in fiscal year 2011 Farm Bill funding for projects that prevent the introduction or spread of plant pests and diseases that threaten U.S. agriculture and the environment. Of those funds, nearly $2 million will be provided to P. ramorum efforts, including survey and analysis of nurseries in 17 participating states, safeguarding nursery systems, and enhanced mitigation through monitoring the efficacy of treatments in wildland areas. To access the FY 2011 funding plan and list of projects, click here.

From the July COMTF newsletter.

Washington received some of this funding to develop biofiltration systems for reducing inoculum of Phytophthora in nursery water.

New water finds of P. ramorum in Washington

2011-07-11T12:03:00.000-07:00

Washington had two new and one repeat P. ramorum-positive waterway detections in June. One of the new positives was detected upstream from a 2010 positive site. The positive stream feeds into the Sammamish River. The other new positive was detected in a watershed sub-basin adjoining the Sammamish River. The repeat detection site has been positive since 2010 and is in a stream that feeds into the Sammamish. While the exact source of the inoculum remains unknown, genetic evidence points toward previously positive nurseries in the associated watershed.

From the July COMTF newsletter

'Super sand' to help clean up dirty drinking water

2011-06-24T09:15:00.000-07:00

And Phytophthora-infested water?

Contaminated water can be cleaned much more effectively using a novel, cheap material, say researchers.

Dubbed "super sand", it could become a low-cost way to purify water in the developing world.

The technology involves coating grains of sand in an oxide of a widely available material called graphite - commonly used as lead in pencils.

Read the rest of the article on BBC News

Updated USDA Regulations Effective June 27 Will Help Stem the Tide of Harmful Non-Native Plants and Pests

2011-06-24T09:13:00.000-07:00

Revised rules will help prevent future infestations of non-native invasive insects, diseases, and plants

ARLINGTON, Va., June 15, 2011 /PRNewswire-USNewswire/ -- The U.S. Department of Agriculture (USDA) has finalized changes to regulations governing international trade in plants used in gardening and landscape design, which will go into effect on June 27, 2011. The Nature Conservancy has encouraged the USDA to revise these antiquated regulations to improve the ongoing efforts by the Department's Animal and Plant Health Inspection Service (APHIS) to prevent potentially invasive plants and pests from entering the country. As was recently discussed in a controversial article in the June 9th edition of Nature magazine, the threat of invasive species is easily – and wrongly – confused as the incrimination of all non-native species. In fact, the regulations finalized by USDA-APHIS have put in place new systems that allow imported materials to be judged by their invasiveness potential, not simply by their non-native status.

Originally adopted in 1918 to protect U.S. agriculture from threats like the plant disease that caused the Irish Potato famine, plant importation regulations have remained largely unchanged. During the intervening 90 years, U.S. imports of plants have mushroomed to 1.4 billion live plants and cuttings and bulbs each year. Between just 1995 and 2002, the volume of seed imported to the United States doubled.

The newly revised regulations will give APHIS needed flexibility to act quickly when it detects a potentially invasive plant or pest that is poised to enter the country and cause economic or environmental damage. The rule change, which has been in process for more than six years, will create a new category called "Not Authorized for Importation Pending Pest Risk Assessment," or NAPPRA. Under this new regulation, APHIS can quickly restrict the import of plants suspected of being invasive or carrying pests until the risks they may pose are properly understood and protective measures can be put into place.

Controlled burn planned in Gig Harbor area

2011-06-07T14:20:00.000-07:00

6/3/11

Controlled burning is scheduled for June 7-8 on Wollochet Drive NW in the vicinity of Fillmore Street near Gig Harbor. The burning is necessary to prevent the spread of the plant pathogen Phytophthora ramorum, commonly known as Sudden Oak Death (SOD).

Sudden Oak Death is a serious plant disease that attacks many types of plants and trees common to the Pacific Northwest. The disease cannot be contracted by humans.

read more here on the Pierce County website

This story is also in

6/8/11 KOMO News

Road crews battling sudden oak death in Gig Harbor

6/3/11 Tacoma News Tribune

Controlled burn planned in Gig Harbor area June 7-8

Slow Sand Filtration Project

2011-06-07T14:16:00.000-07:00

Slow Sand Filtration Project for South Carolina P. ramorum-Positive Nursery – The Clemson University Department of Plant Industry strives to protect SC's agricultural resources and natural ecosystems from the introduction and spread of invasive species such as P. ramorum. One nursery in SC has had positive detections of P. ramorum for three consecutive years. While surveys indicate that eradication efforts have eliminated P. ramorum from nursery stock, the pathogen continues to be found in the nursery's water and soil; however, perimeter forest surveys and stream baiting of the river associated with this nursery have all been negative to date.

In an effort to maintain the pathogen-free status of the natural area outside of the nursery, Clemson University researchers and the nursery owner are installing a slow sand filtration system in which all runoff will be directed into a vegetated ditch that will lead to a small retention pond for sediment dispersal. The water from the pond will be pumped into a slow sand filtration system and then drain to another vegetated area for diffusion before entering the river. Each component of the system will be monitored by Clemson University researchers. The nursery and river will continue to be tested for P. ramorum according to USDA CNP protocol and the state compliance agreement. For more information, email Christel Harden.

From the June COMTF Report

P. ramorum in Washington nurseries

2011-06-07T14:10:00.000-07:00

A Snohomish County wholesale/production nursery was confirmed P. ramorum positive on May 27^th during an Annual Compliance Inspection. The nursery was previously positive in 2008 and 2010. The Confirmed Nursery Protocol, including delimitation of all stock and collection of trace-forward and trace-back information is underway. Though they are under compliance agreement as an interstate host shipper, the nursery has not made an interstate shipment in the past 12 months. Positive species include Mahonia aquifolium, Gaultheria shallon and Arctostaphylos uva-ursi.

From the June COMTF Report

P. ramorum in Washington waterways

2011-06-07T14:08:00.000-07:00

Washington had two repeat P. ramorum-positive waterway detections in May. One of the sites has been positive since 2009 and the other since 2010. Each positive stream feeds into the Sammamish River. Both sites have had positive samples recovered upstream from the confluence of the water course and the Sammamish (baiting by WSDA and WA DNR); the inoculum source for each is unknown.

from the June COMTF report

Oregon nurseries stave off SOD pathogen despite wet weather

2011-05-23T12:33:00.000-07:00

Detections down despite cooler, wetter spring weather

By MATEUSZ PERKOWSKI

Capital Press

Damp and cool conditions are typically conducive to sudden oak death, but Oregon nurseries haven't seen a surge in the fungal-like pathogen despite the dreary weather this spring.

The disease has been detected at three Oregon nurseries so far in 2011, which is the same number as at this point last year, according to the Oregon Department of Agriculture.

During the entire 2010 season, the ODA's testing program found phytophthora ramorum, which causes the disease, at nine nurseries. That's roughly half as many detections as during the peak years of 2004 and 2005.

WSU monitoring on Clarks Creek

2011-05-19T11:04:00.001-07:00

A link to a page on WSU stream monitoring for Phytophthora on Clarks Creek, Puyallup, WA:

http://www.cityofpuyallup.org/services/development-services/puyallups-stormwater-management-program/clarks-creek-initiative/current-restoration-efforts/

Department gives update on Phytophthora ramorum Monitoring

2011-04-14T12:11:00.000-07:00

The Department of Agriculture, Food and the Marine is continuing to survey forests and control outbreaks of the EU regulated plant disease Phytophthora ramorum, a fungus like organism that can damage and kill infected trees and plants. Under EU requirements, annual forest surveys for Phytophthora ramorum have been ongoing since 2003. Until last year, there had been no findings on tree species and P. ramorum had only been detected in forest areas on wild invasive rhododendron shrubs. Following the initial findings in Japanese larch in Ireland in July 2010, an extensive national aerial and ground survey was conducted. These forest surveys have now confirmed the disease in Japanese larch at eleven forest locations in five counties.

Japanese larch appears to be particularly susceptible to the disease, affecting all age classes and locally causing significant dieback and deaths. Noble fir, beech and Spanish chestnut growing in close proximity to the infected Japanese larch have also been found to be infected at a number of the sites and it is likely that the Japanese larch is the source of the infection. The infected trees are being removed to prevent the disease spreading.

Killer disease found in two new species of Irish tree

2011-04-04T12:11:00.000-07:00

Two thirds of Northern Ireland's forests are under threat from a killer tree disease.

The fungal disease P. ramorum (often called Sudden Oak Death) has already infected tens of thousands of Japanese larch trees.

This has led to the felling of over 200 hectares across nine woodlands.

The disease may have jumped species and has infected a Sitka spruce in the Republic of Ireland and several beech trees in County Down, in the north.

If the disease spreads to other Sitka trees it could be a disaster for the Northern Ireland Forestry Service. The species makes up two thirds of all government-owned forests in Northern Ireland.

The disease was already known to be able to infect beech trees. It has also been confirmed that the infection has been found in European larch in England.

BBC News

Read more here

Sudden Oak Death is not going away

2011-03-28T12:14:00.000-07:00

A good description of SOD in California, its hosts, and behavior:

Earlier this month I had the pleasure of visiting the campus at UC Berkeley to attend a training session on Sudden Oak Death (SOD), the disease that has killed many thousands of trees in California and other parts of the world. Losses include many coast live oaks here in Napa County.

To see for yourself, take a short drive up Partrick Road, where the woods are dense. You are likely to spot a number of dead coast live oak trees in this area where SOD was confirmed fairly early in the onset of the epidemic.

The UC Berkeley Forest Pathology and Mycology Lab, which originally identified the disease when it was new to California, continues to refine our understanding of it while it also leads community volunteer efforts to map and mange the disease. The lab sponsors ongoing training for those who are interested in the problem or directly involved in its management.

The March 9 training session, held in the shadow of a large coast live oak by the Tolman Hall portico, was led by lead researcher Matteo Garbelotto, the associate extension specialist and associate adjunct professor who heads the lab research. The lab also sponsors a unique community involvement effort known as “SOD Blitz” days, one of which will be held in Napa on June 4.

Prof. Garbelotto summarized the history of the disease in California from its beginnings to the current state of the research on its biology and management.

Read more here - Trees & People by Bill Pramuk, Napa Valley Register, Saturday, March 26, 2011

Oregon bill targets firewood pests

2011-02-14T09:37:00.000-08:00

Officials want to ensure that ruinous insects aren’t inadvertently imported into the state
By David Steves

--------------------------------------------------------------------------------

SALEM — One way to keep forest-ravaging insects and diseases from hitching a ride into Oregon is to make sure they don’t hide out in firewood brought by out-of-state campers.

That’s the idea behind a proposal that got its first hearing Monday. House Bill 2122 would give the Department of Agriculture authority to regulate out-of-state firewood. Imported wood would have to be treated, most likely with insect- and disease-killing heat. Labels on commercial firewood would have to list the source of the wood and describe its anti-pest treatment if it’s from outside Oregon.

The Register-Guard
Published: Tuesday, Feb 8, 2011 05:01AM

Estimated losses from Sudden Oak Death in CA, USA

2011-02-14T09:32:00.000-08:00

Predicting the economic costs and property value losses attributed to sudden oak death damage in California (2010-2020)

Kovacs et al. 2011. Predicting the economic costs and property value losses attributed to sudden oak death damage in California (2010-2020) Journal of Environmental Management Volume 92, Issue 4, April 2011, Pages 1292-1302. doi:10.1016/j.jenvman.2010.12.018

Abstract

Phytophthora ramorum, cause of sudden oak death, is a quarantined, non-native, invasive forest pathogen resulting in substantial mortality in coastal live oak (Quercus agrifolia) and several other related tree species on the Pacific Coast of the United States. We estimate the discounted cost of oak treatment, removal, and replacement on developed land in California communities using simulations of P. ramorum spread and infection risk over the next decade (2010-2020). An estimated 734 thousand oak trees occur on developed land in communities in the analysis area. The simulations predict an expanding sudden oak death (SOD) infestation that will likely encompass most of northwestern California and warrant treatment, removal, and replacement of more than 10 thousand oak trees with discounted cost of $7.5 million. In addition, we estimate the discounted property losses to single family homes of $135 million. Expanding the land base to include developed land outside as well as inside communities doubles the estimates of the number of oak trees killed and the associated costs and losses. The predicted costs and property value losses are substantial, but many of the damages in urban areas (e.g. potential losses from increased fire and safety risks of the dead trees and the loss of ecosystem service values) are not included.

UK House of Lords debate on SOD

2011-02-14T09:23:00.000-08:00

Trees: Sudden Oak Death — Question
House of Lords debates, 10 February 2011, 11:21 am

Lord Greaves (Liberal Democrat)

To ask Her Majesty's Government what action they are taking to counter the spread of sudden oak death in trees.

Lord Henley (Parliamentary Under Secretary of State, Environment, Food and Rural Affairs; Conservative)

My Lords, the Forestry Commission and the Food and Environment Research Agency, working in partnership with other organisations, are delivering a five-year programme in England and Wales against Phytophthora ramorum. The Government take this very seriously. Infected Japanese larch is being cleared from 7,920 acres of woodland in an effort to halt the spread of the disease.

The rest of the debate

First Report of Phytophthora ramorum Infecting California Red Fir in California

2011-02-10T11:23:00.000-08:00

G. A. Chastagner and K. L. Riley, Department of Plant Pathology, Washington State University Research and Extension Center, Puyallup 98371

September 2010, Volume 94, Number 9
Page 1170
DOI: 10.1094/PDIS-94-9-1170B

Read the article in Plant Disease

First Report of Phytophthora ramorum Infecting Mistletoe in California

2011-02-10T11:03:00.000-08:00

Riley, K. L., and Chastagner, G. A. 2011. First report of Phytophthora ramorum infecting mistletoe in California. Online. Plant Health Progress doi:10.1094/PHP-2011-0209-02-BR.

Read the article here.

An Ecological Approach to Sudden Oak Death Prevention

2011-02-07T10:07:00.000-08:00

In workshops offered recently by Hidden Villa, ecologist Lee Klinger demonstrated ways to prevent Sudden Oak Death. If you've driven through our hills and noticed whole oaks turned brown and dead, you may be looking at an example of this blight on our oak trees.
Klinger's method mimics the effects of forest fires. His theory is that oaks are fire-adapted and thus need periodic fires to remain healthy.

“Fire replenishes minerals, removes competition and reduces sources of acidity such as mosses and lichens.” With Sudden Oak Death, the plant pathogen, phytophthora ramorum, attacks the trees through the trunks.

To mimic the effects of forest fires, he recommends cutting back underbrush that crowds the tree, removing mosses and lichens from the trunk of the oaks, spraying the tree trunk with lime, adding minerals to the soil and topping with compost and mulch.

Read more in the Los Altos Patch

Red alert in Britain's forests as Black death sweeps in

2011-02-07T10:02:00.000-08:00

Just before Christmas, you could stand at the top of Crynant Forest in South Wales and not have a clue that there was a village in the valley below. Today, the view down to the little white houses is uninterrupted. Where in mid-December there were thousands of larch trees, now there is a mass of stumps and branches.

Read the rest of the article in The Telegraph. Ignore the parts about P. ramorum being "a lethal virus from Asia".

Sudden Oak Death Plus Wildfire: A Natural Experiment

2011-02-07T09:54:00.000-08:00

From Oregon to Big Sur, potentially millions of trees have been killed by Sudden Oak Death, or SOD. In 2006 and 2007, researchers from UC Davis set up a large-scale study in the coastal forests near Big Sur to examine the spread of the disease and its impact on forest dynamics. The area was one of the first to be affected by SOD. Members of the Rizzo Lab at UC Davis had established 280 plots across the region, carefully counting and measuring each tree and checking for SOD infection. Then, in June 2008, the Basin Complex Fire ripped through Big Sur, burning over 95,000 hectares of forest. By the time the fire was contained, over a month after it began, one third of the team’s plots were crisp and blackened.

Read more: KQED QUEST Community Science Blog

Forget trees, Welsh uplands needed for growing food

2011-02-07T09:52:00.000-08:00

BRITAIN’S hill and upland areas could be the answer to tackling the growing threat of food shortages, according to a Mid Wales beef and sheep farmer.

John Pugh is calling on the Assembly Government to reconsider its ambitious tree planting strategy, which aims to create 100,000ha of new woodlands over the next 20 years, mainly on marginal hill land.

And he said any plantations cleared to combat Sudden Oak Death should be returned to farmland rather than replanted.

SOD host notification required

2011-02-07T09:37:00.000-08:00

The USDA as of March 1 will require nurseries in certain counties of Oregon, Washington and California to provide advance notice to receiving states when shipping some sudden oak death host material.

Read the rest of the article in the Capitol Press

Sudden oak death now threatens more of Britain's trees

2011-01-18T11:32:00.000-08:00

After destroying millions of oaks in California, the infection spread to Britain – then suddenly jumped species

In woodlands around the UK, just as here in Afan Valley, south Wales, the race is on to fell thousands of trees in a desperate effort to contain a new disease which poses a threat to British forests on a scale not seen since Dutch elm disease wiped out millions of trees, changing the landscape of the country for ever.

Read the article here: The Guardian

Comprehensive report on SOD

2011-01-03T10:22:00.000-08:00

Now available.

Synthesizing more than 10 years of cooperative research on the exotic invasive, quarantine sudden oak death pathogen, the USDA Forest Service's Pacific Southwest Research Station (PSW) recently published "Sudden Oak Death and Phytophthora ramorum: A Summary of the Literature." This 181-page comprehensive report covers a wide range of topics, including a history of sudden oak death, identification and distribution of the disease, epidemiology and modeling, management and control, and economic and environmental impacts.

read the rest of the press release.

Information on how to download or order a free copy of the report, "Sudden Oak Death and Phytophthora ramorum: A Summary of the Literature" can be found at: http://www.fs.fed.us/psw/publications/documents/psw_gtr234/.

Smartphone app for reporting SOD

2011-01-03T10:20:00.000-08:00

And other invasive species too:

Apps are allowing for coordinated monitoring, efficient data collection, and increased communication and cooperation between scientists and the agriculture industry.

Read more: Western Farm Press

Tree deaths affect disease-carrying ticks: Scientists study whether there is a link between tree deaths and Lyme disease

2010-12-20T09:06:00.000-08:00

Over the past 15 years, an invasive plant disease has left a patchwork of dead and dying trees in California's majestic coastal forests. But the loss of trees is changing more than just panoramic views: The number of ticks that can carry a disease that causes painful joint swelling, fatigue and even neurological damage is growing - a result of the gaps created in the forest when trees die, a recent study found.

To determine how the loss of trees affects ticks, their hosts and the Lyme disease they might carry, researchers at UC Berkeley, UC Santa Barbara and the Cary Institute of Ecosystem Studies in New York have embarked on a multi-year study of animal populations in a North San Francisco Bay forest infected with Sudden Oak Death.

read more in the San Jose Mercury-News

Oregon oak disease fight faces federal aid loss

2010-12-13T12:52:00.000-08:00

BROOKINGS, Ore. (AP) — In 2001, U.S. Forest Service plant pathologist Ellen Goheen took to the air to see if sudden oak death was in Oregon.

The disease, which in two years can kill an otherwise healthy oak tree, earlier that year was identified as the causal agent killing huge swaths of oak trees in northern California.

The leading edge of the infestation was more than 100 miles from the Oregon-California border, but Goheen thought it possible that sudden oak death had entered Curry County.

Moments after starting her aerial survey, Goheen's suspicions were realized.

"The 'oh, shoot' factor was pretty high," she said.

Her discovery set off what has become a decade-long, $10 million battle with the fungal disease that threatens much of the West's timber and nursery industries.

http://www.necn.com/12/07/10/Oregon-oak-disease-fight-faces-federal-a/landing_health.html?&blockID=3&apID=5150b7d10ce24702947c0dc2d42fdbb2

More global trade means more forest pests

2010-12-13T12:47:00.000-08:00

Along with U.S. manufacturing jobs, you can count another victim of global trade: American trees.

The most destructive forest pests from abroad are arriving at an accelerated pace, according to a new study. Between 1990 and 2006, new ones were discovered in the U.S. at an average rate of 1.2 per year, or nearly three times the detection rate during the previous 130 years.

The jump coincides with a rise in imports, leading the authors of a paper published in the December issue of BioScience to conclude that current rules and inspections to keep forest pests out of the country aren't that effective.

http://latimesblogs.latimes.com/greenspace/2010/12/foreign-forest-pests-on-the-rise-.html

Public Concern About Invasive Tree Killing Insects and Diseases Remains Strong

2010-12-13T12:40:00.000-08:00

Poll results indicate most Americans are concerned about non-native forest pests and they support measures to stop their spread

ARLINGTON, Va., Dec. 8, 2010 /PRNewswire-USNewswire/ -- Most Americans live near trees, and consider them very important to their quality of life. Recent polling by The Nature Conservancy shows that the American public is well aware of invasive forest pests that kill trees, and are willing to take steps to protect trees from this threat. According to the poll, conducted in September, knowledge of the spread of forest pests such as the Asian longhorned beetle and emerald ash borer, and of diseases like sudden oak death and thousand cankers disease, has increased by 13 percent, from 41 percent in 2005 to 54 percent in 2010. When asked about the issue of forest pests in the most general terms, 93 percent of poll respondents expressed concern. This high level of concern has not changed since 2005, despite the changing economic situation.

http://www.prnewswire.com/news-releases/public-concern-about-invasive-tree-killing-insects-and-diseases-remains-strong-111535019.html

Massive gene loss linked to pathogen's stealthy plant-dependent lifestyle

2010-12-13T12:13:00.000-08:00

An international team of scientists, which includes researchers from Virginia Tech, has cracked the genetic code of a plant pathogen that causes downy mildew disease. Downy mildews are a widespread class of destructive diseases that cause major losses to crops as diverse as maize, grapes, and lettuce. The paper describing the genome sequence of the downy mildew pathogen Hyaloperonospora arabidopsidis, which attacks the widely studied model plant Arabidopsis thaliana, is the cover story of this week's edition of the journal Science.

In the paper, the sequence of H. arabidopsidis is compared with other fully sequenced genomes of destructive plant pathogens to shed light on the differences in the ways microbes interact with their host and how those differences evolve. The payoff could be new ways to investigate how these pathogens wreak havoc and, in the long-term, finding how to prevent billions of dollars of losses for farmers growing crops across the globe.

http://www.eurekalert.org/pub_releases/2010-12/vt-mgl120610.php

Characterizing Douglas-fir Tissue Colonization by the 'Sudden Oak Death' Pathogen, Phytophthora ramorum.

2010-12-07T15:58:00.000-08:00

Characterizing Douglas-fir Tissue Colonization by the 'Sudden Oak Death' Pathogen, Phytophthora ramorum.
By Kathleen McKeever, M.S. and Dr. Gary Chastagner; Department of Plant Pathology, Washington State University Puyallup Research and Extension Center.

In 2001, Koch's Postulates confirmed Douglas-fir as a host for P. ramorum. Naturally-infected saplings have been observed in California forests, and studies on artificially inoculated Douglas-fir stems and shoots have established susceptibility parameters. Although naturally occurring stem infections in the U.S. have been limited to smaller diameter seedlings and saplings, P. ramorum stem cankers were recently observed on 8-year-old plantation grown Douglas-fir in Great Britain in 2009. All previous research has served to substantiate the importance of performing studies to characterize the behavior of P. ramorum in Douglas-fir and assess the potential risk that this pathogen poses to Douglas-fir ecosystems.

Artificial inoculation experiments were carried out to provide a thorough analysis of the colonization of Douglas-fir by P. ramorum. Goals of this research included determining which tissues are colonized by the pathogen, whether woody tissues are able to support sporulation, the likelihood of stem infections occurring on Douglas-fir with intact bark, and the viability of the pathogen in foliage. Methods employed included isolation, ELISA, and histological examination of stem tissues; qPCR and isolation to determine colonization efficacy and viability of the pathogen in needle tissues; and baiting studies to determine the ability of Douglas-fir bark to inhibit colonization of Rhododendron leaves by the pathogen.

ELISA results showed that proteins of the pathogen were detectable in the phloem, cambium, and superficial xylem, with infrequent detection in asymptomatic tissues. The pathogen was able to be isolated from all symptomatic woody tissues tested, but not from non-discolored tissues. ELISA and isolation techniques produced results that were highly positively correlated (r2=0.62, p=0.78), and histological observations paralleled information derived from these techniques. Douglas-fir bark reduced infection on Rhododendron leaf baits by up to 83 percent in the presence of inoculum. Results from foliage inoculations indicated that pathogen DNA is detectable using qPCR methods, but there was an inability to isolate the pathogen from needle tissue. Evidence of spore formation in woody stem tissues has not been observed.

It was concluded that the pathogen may be able to infect into the shallow xylem tissues of Douglas-fir in the presence of wounding, but there was no evidence of sporulation in tissues. The inability to isolate the pathogen from non-discolored tissues suggests that the proteins detected by ELISA outside of the lesion may be elicitins that are secreted in advance of hyphal colonization. The inability to isolate the pathogen from colonized needles may indicate the presence of chemical inhibitors that render the pathogen non-viable subsequent to initial infection. Finally, the ability of Douglas-fir bark to suppress infection of Rhododendron leaf baits suggests that the bark is inhibitory to P. ramorum and that infection of woody stem tissues through intact bark may be limited. Further research is required to identify the nature of this inhibition.

Characterization of P. ramorum colonization of Douglas-fir tissues is relevant to our current understanding of the behavior of the pathogen in different hosts and may enhance our ability to assess risk and create adequate regulations to thwart the spread of this exotic pathogen.

from the December COMTF newsletter

Soil positive for P. ramorum in WA

2010-12-07T15:55:00.000-08:00

A Gig Harbor, Pierce County, WA landscape site adjacent to a previously positive repeat nursery has been found to have P. ramorum-positive soil. The confirmed site is along a drainage that had been found positive with infected salal plants in the summer of 2009. Soil sampling has been ongoing since the initial confirmation; however, this is the first time a positive sample has been recovered. The nursery associated with the site closed in August 2010, yet the retention ponds and outlet for the ponds continue to be positive for the pathogen. The nursery site is currently up for sale. The county has volunteered to remove the remaining host plants and material on the drainage banks where the previous salal find was confirmed in an effort to eliminate the pathogen's ability to become established. Survey work will also continue in the area. For more information, contact Michael Schell at michael.r.schell@aphis.usda.gov.

From the December COMTF newsletter

New research on mating hormone for control of P. infestans

2010-12-07T12:24:00.000-08:00

ScienceDaily (Nov. 17, 2010) — Scientists are reporting a key advance toward development of a way to combat the terrible plant diseases that caused the Irish potato famine and still inflict billions of dollars of damage to crops each year around the world. Their study appears in ACS' journal Organic Letters.

Read the whole article at Science Daily

Battle against Sudden Oak Disease tough, but essential

2010-12-07T11:22:00.000-08:00

As you may have read in the Curry Coastal Pilot, the Oregon Board of Forestry recently met in Brookings and toured areas affected by Sudden Oak Death (SOD), the tree disease caused by the non-native pathogen Phytophthora ramorum. SOD is a relatively new disease to Oregon. Since its discovery in the Brookings area in 2001, forest managers in the public and private sectors have been working together to locate infected trees, eradicate the pathogen from infested sites, and slow the spread of the disease.

Cutting and burning infected and nearby trees may seem crude but it is the best disease management tool available to us. There is nothing we can spray to kill the pathogen or prevent trees from becoming infected. Cutting and burning infected trees, many of them still green, destroys the pathogen and reduces the potential for spread of air-borne spores. Unfortunately, it doesn’t always work as planned. Inconsistent funding often has delayed treatment and allowed the disease to spread before we can destroy it.

http://www.currypilot.com/20101124116570/Opinion/Public-Forums/Battle-against-Sudden-Oak-Disease-tough-but-essential

Plant disease threatens traditions of California tribes

2010-12-07T11:17:00.000-08:00

From 2009:
Mary Larson Bishop gazes at the folds and peaks of the Santa Lucia Range with longing. "I used to go deep into the woods looking for herbs," says the Salinan tribal elder, who is known for her knowledge of medicinal plants such as yerba santa, traditionally used to heal skin inflammation. Now, she no longer roams the Central California coastal hills. "I'm afraid of bringing anything out of the woods that might spread to other trees," says Bishop. "I don't want to track that crud out of the hills."

The "crud" is Phytophthora ramorum, a minuscule waterborne mold that weakens and kills many species of native trees and plants. The pathogen, which causes both Sudden Oak Death and Ramorum blight, was first discovered in the mid-1990s. Since then, it has spread to 14 California counties along the Pacific Coast, and even to Washington and Oregon. It travels by clinging to boots, hands, pant legs and tires.

http://www.hcn.org/issues/41.12/cultural-blight

Deadly P lateralis tree disease found at Loch Lomond

2010-12-07T11:12:00.000-08:00

A deadly tree disease never seen in Britain before has been detected on the shores of Loch Lomond.

P. lateralis is a close relative of P. ramorum and is a root pathogen on Port Orford Cedar.

Read the rest of the article here:

http://www.bbc.co.uk/news/uk-scotland-11879891

OAN makes case to Oregon congressional delegation for action during lame duck session

2010-12-07T11:10:00.000-08:00

OAN supports funding continued efforts to contain and control Phytophthora ramorum, the pathogen that causes sudden oak death. Additionally, our delegation must pressure USDA not to implement its damaging and discriminatory prenofitication rule, requiring all nurseries to notify receiving states of host material shipped from Oregon.

http://oangovernmentrelations.blogspot.com/2010/12/oan-makes-case-to-oregon-congressional.html

Phytophthora ramorum's threat to the East Coast

2010-11-08T16:43:00.000-08:00

Phytophthora ramorum's threat to the East Coast was discussed at the Address P. ramorum Initiative breakout session held at Brandeis University, October 6, 2010, as part of the sixth meeting of the Continental Dialogue of Non-native Insects and Diseases. A poster and handout summarized what is known: The Sudden Oak Death pathogen has been detected in eight rivers in Mississippi, Alabama, Georgia, Florida, and North Carolina. These contaminated waterways are near P. ramorum-positive nurseries. Several of the streams are in areas identified by the USDA Forest Service as "high risk" for infestation due to the presence of susceptible vegetation and suitable climate. The group discussed preliminary plans for 2011, which may include a meeting for interested parties to learn more about the Forest Service "Sudden Oak Death Framework" and recommendations to the USDA Animal and Plant Health Inspection Service from interagency work groups on current P. ramorum regulations. The Address P. ramorum Initiative's goal is to prevent the spread of P. ramorum and work in a collaborative, proactive, cooperative manner. For more information, contact the Initiative co-leads: Ken Rauscher, Jerry Lee, or Susan Frankel.

Buy It Where You Burn It campaign covers OR, WA & ID

2010-10-18T09:52:00.000-07:00

Moving firewood also moves invasive species, including P. ramorum

Buying local firewood protects Oregon forestry and ag
– Imported firewood is a major pathway for invasive species
By Oregon Department of Agriculture

Buy local has a whole new meaning when it comes to protecting Oregon from invasive species this fall and winter. Consumers are urged not to purchase firewood from out-of-state and all the insects and diseases it might carry. Instead, buying local firewood can help keep invasive species from gaining a foothold in the Oregon environment.

“Firewood is a major pathway for moving invasive species, and that’s not a good thing,” says Dan Hilburn, administrator of the Oregon Department of Agriculture’s Plant Division and member of the Oregon Invasive Species Council (OISC). “The take home message to Oregonians is to buy their firewood locally and burn it locally.”

Whether it is used at a campground or at home, people are transporting firewood great distances these days, taking with them any bugs or diseases that might not be native to that area.

http://naturalresourcereport.com/2010/10/buy-it-where-you-burn-it-campaign-covers-or-wa-id/

New nursery research projects at NORS-DUC

2010-10-11T15:30:00.000-07:00

Pending California Department of Pesticide Regulation approval, the following five projects will soon be underway at the National Ornamentals Research Site at Dominican University of California (NORS-DUC). All projects have been funded through the fiscal year federal Farm Bill. For more information on the projects or the NORS-DUC program, contact Sibdas Ghosh at sibdas.ghosh@dominican.edu.

Bostock, R.M. and Roubtsova, T. Episodic abiotic stress and ramorum blight in nursery ornamentals: impacts on symptom expression and chemical management of Phytophthora ramorum in Rhododendron.

Chastagner, G. and Elliott, M. The risk of asymptomatic Phytophthora ramorum infection on fungicide treated rhododendrons.

Jeffers, S.; Meadows, I.; Hwang, J.-S. Studies on Soil Mitigation of Phytophthora ramorum.

Tjosvold, S.; Chastagner, G.; and Elliott, M. Effect of fungicides and biocontrol agents on inoculum production and persistence of Phytophthora ramorum on nursery hosts.

Widmer, T. and Shishkoff, N. Use of Trichoderma spp. to remediate Phytophthora ramorum-infested soil.

Helping to map the SOD outbreak in California

2010-10-11T15:22:00.000-07:00

Sudden oak death: Plotting trail, testing leaves

A map plotting the path of destruction that the tree-strangling pathogen known as sudden oak death is taking through the Bay Area shows new infestations in and around neighborhoods throughout the region.

The effort to track the wily killer's movements is the result of a major effort to involve citizens in the battle against the mysterious pathogen, which has killed tens of thousands of oak trees from Big Sur to southern Oregon.

Read more: San Francisco Chronicle, Oct. 4 2010

Citizen Science

2010-08-30T13:07:00.000-07:00

Citizen science has been around for centuries, with lay people collecting data and making observations for scientists in a variety of fields. And, citizen scientists are contributing to discoveries as much in the 21st century as ever before.

Read more here:
NSF Science Nation -The online magazine that's all about science for the people

and if you're interested in joining WSU's stream monitoring for Phytophthora program, let Marianne know.

P. ramorum spread to Northern Ireland

2010-08-25T12:13:00.000-07:00

Tree killing disease spreads to NI

A private woodland and two government-owned forests in Northern Ireland have been devastated by an outbreak of a killer disease.

It has become known as Sudden Oak Death, but it is really a fungal-like infection that kills Japanese larch trees.

Read the rest of the article here:
BBC News

Research on SOD at Fort Detrick

2010-08-25T12:10:00.000-07:00

Fort Detrick USDA unit a quiet but important part of global food security

On opposite ends of Fort Detrick, overshadowed by the mammoth infectious disease laboratories that sit in between, are two sets of greenhouses belonging to the U.S. Department of Agriculture.
The diseases studied inside aren't as infamous as the anthrax and Ebola tested elsewhere at Fort Detrick, but the USDA research in the greenhouses saves plants vital to the farming, lumber and tourism industries.

Read the rest of the article here:
The Frederick News-Post Online

"Sudden Larch Death" in the UK

2010-08-16T10:28:00.000-07:00

Plant pathology: Sudden larch death
Clive Brasier & Joan Webber
Nature 466:824–825
Date published:(12 August 2010)

doi:10.1038/466824a

An aggressive and unpredictable fungal pathogen is devastating larch plantations in Britain. Its remarkably broad host range, and the possibility of further geographical spread, give heightened cause for concern.

read the whole article here

Adorn fungicide registered for use in California

2010-08-09T10:04:00.000-07:00

Valent’s new chemistry provides control of key diseases, resistance management.

WALNUT CREEK, Calif. – Valent Professional Products announced that Adorn fungicide has been registered for use on ornamentals in California. Adorn is a new chemistry that controls downy mildew, Phytophthora and Pythium in greenhouse, nursery and outdoor landscape settings.

Available for use as a spray or drench, Adorn is effective against a number of diseases affecting California ornamentals, including sudden oak death (SOD) or Phytophthora ramorum. With a new mode of action, Adorn is also an excellent addition to fungicide rotations and plays a key role in resistance management programs when used as part of a tank mix.

Adorn has low-use rates of 1 to 2 ounces per 100 gallons as a drench and 2 to 4 ounces per 100 gallons as a spray. With its translaminar activity, Adorn provides enhanced plant coverage to help ensure growers and LCOs get more from their fungicide.

Lawn & Landscape

Download the label for Adorn Fungicide

Swansea Bay rally halted after tree disease

2010-08-09T09:59:00.000-07:00

The Swansea Bay Rally, postponed last month due to a tree disease, has been cancelled for 2010, say organisers.

The event, due to start and finish outside Swansea Museum on 17 July, was called off at short notice.

The route, near Resolven and Rhondda, went through areas that have been hit by the Phytophthora ramorum infection, also known as as "sudden oak death".

Rally organisers said the event could not be re-scheduled to take other qualifying rounds into account.

The rally, which has been running for almost 40 years, is part of the MSA National Gravel Rally Championship.

Around 80 semi-professional and club drivers were due to take part.

read the whole article on BBC News

Research projects funded by USFS

2010-08-03T13:08:00.000-07:00

Including some at WSU:

The USDA Forest Service, Pacific Southwest Research Station Sudden Oak Death/P. ramorum research program list of 2010 funded projects is now available at http://www.fs.fed.us/psw/programs/sod/funding/FY2010PSWSODFunding.pdf.

Thirteen new projects as well as 14 continuing projects were funded, for a total of $1,401,441. For more information, contact Susan Frankel at sfrankel@fs.fed.us.

Nursery update for WA and OR

2010-08-03T13:04:00.000-07:00

A King County, Washington retail nursery was found to have six
P. ramorum-positive rhododendrons in July. This nursery was also found positive for the pathogen in 2004, 2005, and 2006. CNP is underway. To date in 2010, the Washington State Department of Agriculture has processed more than 13,000 samples and detected P. ramorum at eight nurseries. For more information, contact Brad White at bwhite@agr.wa.gov.

A Washington County, Oregon retail nursery was found with two
P. ramorum-positive Rhododendron plants in mid-July. The nursery requested a survey after identifying a potential out-of-state customer. Prior to the confirmation, the nursery had not shipped interstate. This is the first time P. ramorum has been detected in this nursery. The USDA Retail CNP has been enacted.

As of 7/21, the Oregon Department of Agriculture has completed testing for the 2010 P. ramorum Federal Order Survey on 15,670 samples collected from 392 nursery grower locations. So far, P. ramorum has been detected in seven Oregon nurseries, with three nurseries having completed the CNP. For more information, contact Nancy Osterbauer at nosterba@oda.state.or.us.

From the August COMTF newsletter

SOD situation in Britain

2010-08-03T13:00:00.000-07:00

Britain's Forestry Commission is continuing to try to minimize the spread of P. ramorum by felling tens of thousands of Japanese larch (Larix kaempferi), first found to be a sporulating host in southwest England in fall 2009. Since then, thousands of trees have died. Follow-up aerial surveys in southwest England and Wales, and up into western Scotland, have identified 203 suspicious sites in a mix of privately owned and Forestry Commission public woodlands in England and Wales. Of these, 42 sites in southwest England and eight in Wales have confirmed infestations. More than 30 hectares of trees were felled last winter, with an additional 250 hectares planned for removal this summer and fall. Felling is continuing in the southwest England counties of Devon and Cornwall, including Plym Woods, a popular forest for public recreation near the city of Plymouth, and is getting under way in Wales. The Forestry Commission hopes that by taking decisive action in southwest England and south Wales it can prevent the pathogen from spreading further into Britain.

Affected forests are remaining open to visitors, except for areas where felling is taking place, due to safety reasons. Visitors are being asked to stay on stone paths, keep dogs on short leads, and clean shoes and bikes before leaving infested areas. Private landowners are also being asked to regularly inspect woodlands where larch is present and to report any suspected P. ramorum outbreaks to the Forestry Commission. For more information, go to http://www.forestry.gov.uk/pramorum.

From the August COMTF newsletter

Key Finding: Many Pathogenic Fungi Use the Same Entrance to Invade Host Cells

2010-07-26T09:25:00.000-07:00

Some crop--and even human--diseases might be stopped dead in their tracks if researchers can harness a new discovery about how pathogens first infect their hosts.

Like a burglar with a universal lock pick, many deadly pathogens use the same protein to gain access to the cells of a potential host, researchers have discovered. The new findings could have implications for blocking infections by agents ranging from wheat rust to malaria.

Pathogenic fungi, such as flax rust and soybean rust, and similar pathogens known as oomycetes, such as the organism behind the Irish potato famine and sudden oak death, make similar proteins to disarm their hosts' defenses. But to work, these effector proteins need to first make their way inside of a cell. And until now, scientists did not know, in the first place, how these compounds were able to break in.

A new study, published online July 22 in Cell describes how these blights do it.

Read the full article in Scientific American

2010-07-12T09:50:00.001-07:00

Schmidt, D. and Garbelotto, M. 2010. Efficacy of phosphonate treatments against Sudden Oak Death in tanoaks. Phytopathology 100:S115.

Pytophthora ramorum, the causal agent of Sudden Oak Death (SOD), has killed hundreds of thousands of trees in California and Oregon. Tanoaks (Lithocarpus densiflorus) are both stem and foliar hosts and, as such, die from SOD and help spread the disease. Phosphonate treatments are routinely used in agricultural and orchard crops affected by Phytophthora diseases. We have developed a detached-leaf bioassay for studying the effectiveness of phosphonate treatments for SOD in tanoaks. The assay involves infecting the petioles of tanoak leaves with agar plugs of P. ramorum in culture. SOD infection is analyzed by examining the spread of P. ramorum down the midrib of the leaf. This assay has shown that tanoaks in wildland settings, treated with phosphonates, are resistant to SOD infection. In addition, we are maintaining long-term studies of tanoaks treated with phosphonates in SOD infected forest areas. Paired 20mx20m treatment and control plots were established near existing SOD infections. The trees were evaluated for disease symptoms and general health prior to the initial treatment and each subsequent year. The results show that phosphonate treatments are effective at slowing and preventing the spread of the disease in the treated areas. Treatments at the leading edge of SOD infected areas were less effective, confirming that phosphonate treatments are significantly more effective as preventative rather than curative treatments.

Phytophthora species in streams

2010-07-12T09:48:00.000-07:00

Hwang, J.; Jeffers, S.N.; and Oak, S.W. 2010. Aquatic habitats—A reservoir for population diversity in the genus Phytophthora. Phytopathology 100:S150.

Occurrences of oak decline and sudden oak death in forests of Europe and the west coast of the U.S.A., respectively, have focused attention on the species of Phytophthora present in natural ecosystems. We have been investigating the diversity of species of Phytophthora present in forest streams in the eastern U.S.A. Phytophthora spp. are well adapted to aquatic environments and can be recovered from stream water by baiting and filtration. Extensive surveys in multiple states revealed that a diversity of species occurs naturally in forest streams. In one study, five forest streams in western North Carolina were monitored monthly for a year. Seven species—P. cambivora, P. cinnamomi, P. citricola, P. citrophthora, P. gonapodyides, P. heveae, and P. pseudosyringae—and seven morphologically and genetically distinct groups of isolates were detected. Samples of stream-side soils and plants with symptoms also were collected, but only three species were detected: P. cinnamomi and P. heveae in soils and P. citricola and P. heveae on plants. Species of Phytophthora consistently were detected in streams during winter months when air temperatures were near or below freezing, which are not conducive to lesion development and sporulation. These results suggest that the native population of Phytophthora spp. in stream water is different from those in terrestrial habitats. The species of Phytophthora present in streams may occupy a unique niche—i.e., they appear to be aquatic inhabitants and not transient visitors.

Genetic diversity of P. ramorum population in Canada

2010-07-12T09:46:00.000-07:00

Goss, E.M.; Larsen, M.; Vercauteren, A.; Werres, S.; Heungens, K.; and Grunwald, N.J. 2010. Genotypic diversity of Phytophthora ramorum in Canada. Phytopathology 100:S42.

Characterization of the genetic structure and diversity of the sudden oak death pathogen, Phythophthora ramorum, in ornamental nurseries in the United States has shown that all three known clonal lineages of the pathogen are present. The most common clonal lineage in U.S. nurseries has been the NA1 clonal lineage, which has the wider distribution in the United States as a result of interstate shipments of infected nursery stock. British Columbia (BC), Canada is also known to have nursery infestations of P. ramorum, and shipments of infected plants between the United States and BC have occurred. We investigated the genotypic diversity of P. ramorum in BC nurseries and compared this population to U.S. and European nursery populations. All three of the P. ramorum clonal lineages were found among Canadian nursery isolates, but the most common was the NA2 lineage. The NA1 clonal lineage was found infrequently in comparison to the United States. The EU1 lineage was observed almost every year and shared multilocus genotypes with isolates from Europe and the United States. Appropriate markers for the characterization of the NA2 lineage are needed.

Stream in NC positive for P. ramorum

2010-07-12T09:43:00.000-07:00

Water draining an infested nursery in Mecklenburg County (Charlotte), NC has been found to have Phytophthora ramorum as a result of the 2010 National P. ramorum Early Detection Survey of Forests. The rhododendron leaf baits were deployed by survey cooperators in the NC Forest Service and diagnosis made from several baiting periods via PCR by the survey's Eastern Regional Diagnostic Lab at the Pennsylvania Department of Agriculture. This brings the total number of positive waterways to 10 in six states outside areas where P. ramorum is found in California and Oregon forest areas (WA [2], AL [4], MS [1], GA [1], FL [1], and NC [1]). Cooperative streamside vegetation surveys are being planned for the fall by the USDA Forest Service, NC Forest Service, and NC Department of Agriculture and Consumer Services to determine if the pathogen has become established in terrestrial ecosystems.

from COMTF July newsletter

Agency delays plan targeting sudden oak death

2010-06-28T09:13:00.000-07:00

Nurseries say APHIS order provides more paperwork, but not more protection

By MITCH LIES

Capital Press

Federal officials provided West Coast nurseries breathing room this week when they delayed a new requirement for shipping nursery stock that can host sudden oak death.

But the delay falls short of easing industry concerns.

USDA Animal and Plant Health Inspection Service officials earlier this month told West Coast agriculture officials they planned to delay by as much as three weeks implementation of the federal order. It was initially scheduled to start June 21.

The order requires nurseries in Oregon, Washington and California to notify receiving states in writing when they ship nursery stock that can host Phytophthora ramorum, the fungus associated with sudden oak death.

Read the full article here - http://www.capitalpress.com/orewash/ml-sod-federal-order-062510

Two nurseries positive for P. ramorum in May

2010-06-17T11:17:00.000-07:00

Washington was found to have two P. ramorum-positive nurseries in May. (1) On 5/3 a Thurston County wholesale/production nursery was found to have P. ramorum-positive Mahonia nervosa and Viburnum tinus as a result of a nursery compliance inspection. This nursery ships interstate and was previously positive for P. ramorum in 2008. Trace-forward and -back investigations are underway. (2) A Snohomish County wholesale nursery was determined to have P. ramorum-positive Rhododendron sp. on 5/6 as a result of a nursery compliance inspection. This nursery ships interstate and was previously positive for P. ramorum in 2008. Trace-forward and -back investigations are underway.

A Tale of Three Nurseries

2010-06-14T12:43:00.000-07:00

A heartwarming (or frightening) tale of three nurseries, reposted from the Oregon Invasive Species blog:

Once upon a time there were three nurseries. As long as people could remember, these nurseries had been growing and selling plants to satisfied customers. The nurseries were called: Clean and Green, Pretty Good Plants, and Cuttin Corners....

read the whole story here:
http://oregoninvasivespecies.blogspot.com/2010/06/tale-of-three-nurseries.html

SOD found in South Wales on larch

2010-06-14T12:31:00.000-07:00

Forestry Commission experts are working to contain the spread of Phytophthora ramorum infection to Japanese larch trees in South Wales.

Phytophthora ramorum (P. ramorum) is a fungus-like pathogen that kills many of the trees and plants that it infects. Japanese larch trees infected by P. ramorum were first found in South West England last year, the only place in the world where it has attacked large numbers of a commercially grown species of conifer tree.

This development was a step change in the pathogen’s behaviour. Since first being identified in Britain in 2002, on a viburnum plant in a garden centre, it had affected mostly shrub and ground-cover plants such as rhododendron, viburnum and bilberry. Fewer than 100 infected trees – mostly beech - had been found, and most of those were standing close to infected rhododendron bushes.

Although it has been confirmed in only one area of larch forest in Wales so far, Forestry Commission Wales expects to find more as ground inspections follow up the aerial surveys that have pinpointed suspect areas of woodland. Scientists at the Commission’s Forest Research arm believe it likely that the spores that spread the disease have been spread to the larch forests in rain, mists and air currents carried across the Bristol Channel from the South-west, where it was confirmed in Japanese larch last September.

Roddie Burgess, Head of the Forestry Commission’s Plant Health Service, said the Commission and its partners are taking the development very seriously, but hope to be able to contain it.

Read the complete article here:

http://www.forestry.gov.uk/newsrele.nsf/AllByUNID/11FB60906B36B2C68025773D005CD276

How pathogens can survive in aquatic environments

2010-05-05T13:02:00.000-07:00

This article may give some insights into how P. ramorum can persist in a stream environment:

Islands of Germs: Researchers Discover Pathogens Floating on Tiny Clumps of Aquatic Detritus

Researchers have found evidence that "marine snow"--aggregates of organic material floating in water bodies--may act as microscopic, island-like refuges for pathogens, or disease-causing organisms. This detritus may skew water sampling procedures and mathematical models used to predict the transmission of waterborne diseases to humans.

(follow the link above to read the whole article)

WSU stream monitoring program

2010-05-05T12:58:00.000-07:00

The Washington State University, Puyallup (WSU-P) SOD community-based stream monitoring program was piloted in March 2010 in Washington's Puget Sound region. In addition to increasing the number of streams monitored for P. ramorum throughout the state by the Washington State Department of Agriculture (WSDA) and Washington Department of Natural Resources (WADNR), the new program also has potential to increase community awareness about the spread of P. ramorum and other Phytophthoras in streams. WSU-P received two years worth of funding from the USDA Forest Service to manage this program, which involves Master Gardeners, high school and college students, and other volunteers. Baiting sites were chosen based on discussions with WSDA and WADNR, and also volunteer availability. In 2010 four sites are being monitored for six two-week intervals and three sites for one two-week interval. The two-week interval sites are part of class projects for UW-Tacoma and Pierce College. Some students are also doing projects in the lab related to disinfectant use and survival in saline conditions. The program will be expanded in 2011. No P. ramorum has been detected at any of the sites so far. For more information, go to http://www.puyallup.wsu.edu/ppo/sod/monitoring/stream%20monitoring.htm or contact Marianne Elliott at melliott2@wsu.edu.

From the May COMTF newsletter

WSDA survey results

2010-05-05T12:55:00.000-07:00

The Washington State Department of Agriculture (WSDA) has surveyed 30 host and non-host nurseries to date this year for P. ramorum, all of which have been negative for the pathogen. Some shippers in the state have greatly reduced the amount of high-risk genera (Camellia, Rhododendron, Pieris, Viburnum, and Kalmia) inventory for sale in an effort to reduce the risk of a P. ramorum find. However, two nurseries continue to yield positive water samples - one in Pierce County and one in King County. These sites continue to be monitored as no infected plants have been found in association with the positive water and the inoculum source is unknown. February and April surveys of plants downstream from the Pierce County positive nursery perimeter salal find in 2009 found no positive plants, and the Rosedale Stream has been continuously baited since January 2010, with no positive water finds. WSDA also followed up on trace-forward investigations from a Pennsylvania positive nursery, of which all 160 Laurus nobilis imported plants were free of P. ramorum.

From the May COMTF newsletter

A new invasive species on the landscape

2010-04-16T12:47:00.001-07:00

Not a Phytophthora, but still -beware!

Gnome Management in the Garden

'PC' disease devastating African palm plantations

2010-04-15T15:37:00.000-07:00

Another destructive Phytophthora disease (P. palmivora) attacking oil palms in the tropics:

http://seattletimes.nwsource.com/html/nationworld/2011597413_palmoil14.html

Nursery news

2010-04-08T09:25:00.000-07:00

A Clark County, WA production nursery was found to have P. ramorum infested soil on 3/10/10. A delimiting survey was conducted. This nursery was also found P. ramorum positive in 2008 and 2009.

From the April COMTF newsletter

Update on conifer hosts of P. ramorum in the UK

2010-04-08T09:20:00.000-07:00

This is of interest to Washington because Douglas-fir and western hemlock are important forest species here:

"The 2009 UK sites where Japanese larch (Larix kaempferi) were found with Phytophthora ramorum foliar and stem infections, yet not in close proximity to Rhododendron ponticum, have more recently been found to have a range of other woodland and commercial plantation species affected by the pathogen (primarily bole canker infections). Tests conducted by UK Forest Research have shown that the Japanese larch foliage strongly supports P. ramorum sporulation, possibly even to the extent seen on California bay laurel (Umbellularia californica). Foliar infections on larch appear to be able to generate hundreds and even thousands of sporangia on a single infected needle. This inoculum load high in the crowns of affected Japanese larch has likely lead to widespread local infection on the foliage and boles of nearby susceptible tree and understory species, as well as caused bole infections on the larch.
Affected species of the larch understory include beech (Fagus sylvatica), sweet chestnut (Castanea sativa), and oak species (Quercus spp), all of which are known to suffer from bole cankers, as well as birch (Betula pendula), which has not previously been found as a bole host. Over the past 6 months a number of conifer species have also emerged as bole hosts, including western hemlock (Tsuga heterophylla), Port Orford cedar (Chamaecyparis lawsoniana), and Douglas-fir (Pseudotsuga menziesii); however, only one or two individuals of these conifer hosts have so far been confirmed P. ramorum positive. Western hemlock has also been confirmed as a foliar host of the pathogen.
This upsurge in P. ramorum and the many new hosts that are emerging is strongly correlated with proximity to larch exhibiting crown dieback. The number of sites where this is known to be occurring is limited. Control measures are now underway, which includes felling the larch to prevent further sporulation following budburst in the spring. For more information and details of symptoms, go to http://www.forestry.gov.uk/forestry/INFD-7XVEWH and http://www.forestry.gov.uk/website/forestry.nsf/byunique/infd-5vfmzu "

from the April COMTF newsletter

HERB GARDENING ENTHUSIASTS CAN HELP DETECT INVASIVE PLANT DISEASE

2010-04-08T09:12:00.000-07:00

HERB GARDENING ENTHUSIASTS CAN HELP DETECT
INVASIVE PLANT DISEASE

Since destructive pests are often impossible to control once established, early detection is key to stopping their spread

ARLINGTON, VA—April 7, 2010 – Until proposed revisions to the regulations governing international plant trade, currently under review, are approved by the U.S. Department of Agriculture (USDA), homeowners can play an important role in detection and reporting of invasive insects and diseases. New non-native plant pest introductions are detected at a rate of one every 12 days, adding to the burden of the approximately 400 tree pests already established in the United States. These pests can wreak havoc in homeowners’ yards, and then move through neighborhoods and to nearby forests, causing costly and widespread destruction.

The Nature Conservancy, along with nursery industry partners and scientists, is supporting these revamped regulations in its ongoing efforts to block non-native insects and diseases. If implemented, the USDA rules would create a new category called NAPPRA (Not Authorized for Importation Pending Pest Risk Assessment), under which the nation could quickly stop the import of some plants suspected of harboring pests until procedures can be implemented to ensure they are safe.

“Vigilant homeowners and gardeners have been the ones to detect the presence of foreign pests that had previously gone undetected in many areas,” says Faith Campbell, senior policy representative in the Conservancy’s Forest Health Program. “A Massachusetts homeowner, who found a strange-looking bug in her backyard and reported it to the appropriate government agency, helped prevent the Asian long-horned beetle from spreading through the United States.”

Earlier this year, an alert greenhouse owner in Pennsylvania saw odd symptoms on his seedling bay laurel or sweet bay (Latin: Laurus nobilis). Experts confirmed that the plants were infected by the pathogen that causes “sudden oak death” (Latin: Phytophthora ramorum), a disease that has killed over a million trees in California. This is not the first detection of the pathogen in Pennsylvania or the eastern United States; however, to date, there have been no detections of the pathogen in the forestry environment on the East Coast.

This disease is known to attack several kinds of oaks, magnolias, rhododendrons, and mountain laurel. Bay laurel is a popular herb often grown by gardeners. If homeowners have recently bought bay laurel seedlings or seeds, they should examine these plants carefully. If the plants have dead or dying leaf tips or the entire plants are dead or dying, those symptoms may be caused by:
· too much water
· too little water
· too much fertilizer
· chilling or freeze damage
· infection by the sudden oak death pathogen or some other disease agent

If homeowners rule out all the causes except for the presence of a disease, they should contact their state department of agriculture to find out where to send a sample of it and how it should be packaged to ensure spores cannot escape during shipment. A state’s chief plant pest regulator can be found at www.nationalplantboard.org/member/index.html.

Additionally, as homeowners nationwide begin their general yard clean-up and spring gardening, they should be aware that other plants and trees might be carrying a damaging insect or disease. If they notice any insects or a blight or disease they don’t recognize, they can take a photo or specimen of it to their local nurseries or use Internet resources such as http://invasivepests.org/photosmore.html to help them identify it. If they suspect they may have found an invasive pest or pathogen, they should contact the local government department that oversees agriculture or forestry to alert them to the discovery and gain assistance in confirming its identity.

Following are some of the most prevalent invasive insects and diseases, and the regions which are currently threatened by their encroachment.

Non-Native Pest Regions at risk
hemlock woolly adelgid ---- Appalachian Mountain region

laurel wilt & ambrosia beetle ---- coastal regions from South Carolina to Mississippi; Florida

sudden oak death ---- coastal regions of California and Oregon

Asian longhorned beetle ---- New England; New York and New Jersey; Chicago metropolitan area

More detailed information about and photos of these and other invasive pests can be found at http://www.invasivepests.org/.

###
The Nature Conservancy is a leading conservation organization working around the world to protect ecologically important lands and waters for nature and people. The Conservancy and its more than one million members have been responsible for the protection of more than 18 million acres in the United States and have helped preserve more than 117 million acres in Latin America, the Caribbean, Asia and the Pacific. Visit us on the Web at http://www.nature.org/.

The Continental Dialogue on Non-Native Forest Insects and Diseases is a group of organizations and individuals that cultivates and catalyzes collaborative action among diverse interests to abate the threat to North American forests from non-native insects and diseases.

Phytophthora ramorum has been detected in Pennsylvania on Bay (Laurus nobilis)

2010-04-01T11:14:00.000-07:00

Another pathway by which P. ramorum can be introduced is described below:

"On Feb. 18, 2010 the Penn State Plant Disease Clinic received a sample of Laurus nobilis, known commonly as bay laurel, true laurel, sweet bay,laurel tree, Grecian laurel, or bay tree. Some people use its leaves in cooking. The tips of the leaves submitted were dead or dying and it was reported by the grower that 95% of well rooted plants in 12 or so flats exhibited the symptoms. The United States Department of Agriculture-Animal Plant Health Inspection Service (USDA-APHIS) confirmed the plants to be infected with Phytophthora ramorum, the Sudden Oak Death pathogen known to occur in trees and shrubs on the west coast of the U.S. and in Europe. The sample came from a commercial, primarily wholesale, greenhouse in eastern Pennsylvania. Phytophthora ramorum can infect many important ornamental trees and shrubs under the right conditions. There is a great deal of concern that this fungus-like organism could cause significant economic damage to eastern forests and landscapes if not excluded from the region.The’ bay laurel’ submitted was not Umbelluiaria californica, the California bay or California bay laurel that grows on the west coast and is a major host of Phytophthora ramorum that then spreads to oaks. However, Laurus nobilis is known to be a host of Ph. ramorum.The actual source of the Ph. ramorum in Pennsylvania is still under investigation and is very much in question. The infected plants had been grown in Pennsylvania from seed obtained from a source in California. As yet, there are no known cases of Ph. ramorum being seedborne. I learned recently that the ‘seed’ is sometimes received not as cleaned seed but as seed still in the drupe (fruit). That raises the possibility that the pathogen may have been in parts of the fruit other than the actual seed. It is also possible that the pathogen was infecting other plants in the greenhouse and spread to the Laurus. APHIS is doing ‘trace backward’ investigations to determine where the pathogen may have come from and‘trace forwards’ to determine whether various plants sold by the Pennsylvania greenhouse are carrying the pathogen.

Phytophthora ramorum has, to date, been excluded from the eastern U.S. but this occurrence may indicate that the plant pathogen is now or will soon be in the region from multiple sources. In 2009, Laurus nobilis was named as the Herb of the Year by the International Herb Association (IHA). Laurus nobilis seed can be purchased from a number of sources including through Amazon.com. Web information indicates that the seed is difficult to germinate. It is my understanding that people have been encouraged to grow this plant and that it has been used in various Master Gardener projects. If seed or tissue associated with seed is actually the source of the pathogen, it is possible that Phytophthora ramorum has arrived in the east with seed purchased bybackyard gardeners, etc. Where is the ‘failed to germinate’ material discarded? Where are plants with dying leaf tips discarded? The photo below (and attached) is of the actual sample as it arrived at Penn State. It is not very impressive. If you are presented with Laurus nobilis plants with dead or dying leaf tips or entire plants dead or dying…those symptoms may be caused by:

too much water

too little water

too much fertilizer

chilling or freeze damage

Phytophthora ramorum infection

There is much we don’t know about the circumstances surrounding this occurrence and, therefore, we can’t release specifics such as the name of the greenhouse. But, the information above can be used in newsletters,training sessions, news releases, grower presentations, etc."

Gary W. Moorman, Prof. of Plant Pathology

The Pennsylvania State University, Department of Plant Pathology

Shift in Phytophthora ramorum populations in Washington State

2010-03-03T12:06:00.000-08:00

The EU1 strain is now the most common P. ramorum lineage detected in WA state nurseries and non-nursery sites, with a concurrent rise in NA2 and decrease in NA1. Evaluation of genotypes over the past 5 years by Gary Chastagner, Katie Coats, and Marianne Elliott at Washington State University shows the reversal in genotype frequency occurred in 2008 and persisted into 2009. They detected EU1 in 99 positive samples at seven locations, NA1 in 17 samples at four sites, and NA2 in 48 samples at three sites in 2009. In contrast, the first year of the study (2005) identified four EU1 samples at one site, 103 NA1 samples at 14 sites, and 12 NA2 samples at five sites.
Of the 46 Washington nurseries found positive since 2003, five had infected plant detections in 2009. Twenty nurseries have been confirmed positive at least two years. Two of these sites were found to have positive plants three different years and two sites were positive four years. Genotype analysis has been performed on samples from 31 nurseries since 2005. Of the nurseries with multiple confirmed years, six had various combinations of two lineages for one or two years and one had a year with all three lineages followed by two other years with two lineages present each year.
Nine Washington non-nursery sites (landscapes, water, soil or trace-forward landscape plants) have also been identified P. ramorum positive since 2005, with seven sites having been positive in 2008 and/or 2009. Of the seven sites, the Rosedale Stream (Pierce County) has been found positive for four years (NA1) and the Sammamish River (King County) has been confirmed positive for three years (several lineages). A Pierce County site with NA2-positive salal plants was also found adjacent to nursery property, and four residential sites have been found in the past two years, all of which have been identified with the EU1 strain (two residences were found with the EU1 strain in 2008 and 2009, one with plants and soil, and one with just soil). These four residential sites were trace-forwards from the same EU1-positive nursery.
In 2009, a new systematic sampling method was implemented, which involved not only genotyping the original DNA sample, but also a second round of sampling using the same plant and/or bait material from which the DNA positive was detected. In addition, through a cooperative effort with the Washington State Department of Agriculture and the USDA Animal and Plant Health Inspection Service (APHIS), a third round of sampling was performed on whole plants or plant material collected from most of the nurseries prior to destruction of the plant material. This duplicate and triplicate sampling allowed for a better representation of the genetic distribution of the P. ramorum population.
In total, 450 samples from 31 nurseries, three water sites, and six landscape locations have been analyzed. For more information on the study and its findings, contact Gary Chastagner at chastag@wsu.edu.

From the COMTF March newsletter

New species added to the host list

2010-03-03T11:58:00.000-08:00

Ten species have been added to the list of federally regulated P. ramorum associated host plants. The USDA Animal and Plant Health Inspection Service (APHIS) issued the on 2/22/10, adding Mexican-orange (Choisya ternate), kousa dogwood (Cornus kousa), Daphniphyllum glaucescens, European holly (Ilex aquifolium), Japanese-oak (Lithocarpus glaber), Magnolia cavalieri, Magnolia foveolata, bayleaf currant (Ribes laurifolium), bilberry (Vaccinium myrtillus), and lingon berry (Vaccinium vitis-idaea) to the list. Symptoms for each of the new hosts other than bilberry were leaf necrosis. Tip dieback occurs in infected bilberry as well as Daphniphyllum glaucescens These species were identified as susceptible by the Canadian Food Inspection Agency (CFIA) and the United Kingdom's Food and Environment Research Agency (FERA).
Nurseries currently operating under an APHIS P. ramorum compliance agreement are able to continue shipping hosts and associated plants, including the newly listed plants; however, any nurseries not currently under a compliance agreement that contain these new species must be properly inspected, sampled, tested, and placed under a Compliance Agreement by 3/31/10 in order to be able to move any plants interstate.

From the COMTF March newsletter

News from California and the rest of the US

2010-02-15T09:23:00.000-08:00

Warm, wet weather caused by El Nino is a "free ticket to Disneyland" for P. ramorum in California, providing an environment in which the disease can spread:

http://www.napavalleyregister.com/lifestyles/home-and-garden/columnists/bill-pramuk/article_60416e9e-184e-11df-bfaf-001cc4c002e0.html

Researchers at University of North Carolina are developing a model to predict spread of P. ramorum if it were to get loose in the eastern US:

http://www.newsobserver.com/news/local_state/story/314528.html

NA2 lineage found on salal, additional positive nurseries

2010-02-09T09:15:00.000-08:00

As part of the perimeter survey conducted at a P. ramorum-positive retail nursery in Pierce County, Washington last summer, the Washington State Department of Agriculture identified infested salal (Gaultheria shallon) plants in the natural landscape (as reported in the COMTF August 2009 Newsletter). Follow-up analysis of the samples by the Chastagner lab at Washington State University has resulted in the isolation of the NA2 lineage from the salal. This is the first detection of the NA2 lineage on native forest vegetation. For more information on this development, contact Gary Chastagner at chastag@wsu.edu.

Washington had two P. ramorum-positive locations identified in January. Both sites have previously been found positive for the pathogen. One positive find was in retention pond water at a Pierce County retail nursery. Treatment of the pond (located on nursery property) is optional as it is not used for irrigation or fire suppression. The second site was in a Mason County church landscape where an assumed-positive Viburnum tinus was identified as part of a Thurston County nursery trace-forward investigation. Follow-up efforts have determined that the viburnum did not transit through the Thurston County nursery, but rather was sourced from Oregon. It is unknown where the plant potentially became infested. The Oregon nursery from which the plant originated completed the CNP in December (2009). WSDA PCR results on the viburnum were inconclusive; results are pending from Beltsville, MD.

From the February COMTF newsletter

Japanese larch and Western hemlock new hosts for P. ramorum in the UK

2010-02-02T08:53:00.000-08:00

"Since August 2009, significant numbers of Japanese larch trees have begun to show symptoms of needle loss and dieback in Devon, Cornwall and Somerset. The number of trees affected, and the apparent speed of the decline is a cause for concern – some trees are already dead. Smaller numbers of broadleaf trees associated with the larch were found to have symptoms of bleeding cankers, and closer examination by Forest Research scientists revealed that these broadleaf trees were infected with Phytophthora ramorum. This is the fungus-like pathogen responsible for the phenomenon known as “sudden oak death” in the USA, where it has killed millions of trees including the native American tanoak. "

read more here

new song - Sudden Oak Death

2009-11-30T08:41:00.000-08:00

Listen to Sudden Oak Death - Mountain Goats & John Vanderslice on Moon Colony Bloodbath for free on Grooveshark.

http://listen.grooveshark.com/#/song/Sudden_Oak_Death/22781967

'Oak death' affects medieval site

2009-11-30T08:39:00.000-08:00

Trees and shrubs surrounding a medieval monument in Cardiff are to be removed and burned after a plant disease which can be deadly to trees was found.
http://news.bbc.co.uk/2/hi/uk_news/wales/south_east/8377637.stm

California bans Curry County's Douglas Christmas trees

2009-11-30T08:29:00.000-08:00

But Grand fir and Noble fir are ok?

Read the article here:
http://www.currypilot.com/20091128114288/News/Local-News/California-bans-Curry-Countys-Douglas-Christmas-trees

New article: Population genetics and migration of P. ramorum

2009-10-12T08:29:00.002-07:00

Goss, E.M.; Larsen, M.; Chastagner, G.A.; Givens, D.R.; and Grünwald, N.J. 2009. Population genetic analysis infers migration pathways of Phytophthora ramorum in US nurseries. PLoS Pathogens 5(9): e1000583.
Abstract: Recently introduced, exotic plant pathogens may exhibit low genetic diversity and be limited to clonal reproduction. However, rapidly mutating molecular markers such as microsatellites can reveal genetic variation within these populations and be used to model putative migration patterns. Phytophthora ramorum is the exotic pathogen, discovered in the late 1990s, that is responsible for sudden oak death in California forests and ramorum blight of common ornamentals. The nursery trade has moved this pathogen from source populations on the West Coast to locations across the United States, thus risking introduction to other native forests. We examined the genetic diversity of P. ramorum in United States nurseries by microsatellite genotyping 279 isolates collected from 19 states between 2004 and 2007. Of the three known P. ramorum clonal lineages, the most common and genetically diverse lineage in the sample was NA1. Two eastward migration pathways were revealed in the clustering of NA1 isolates into two groups, one containing isolates from Connecticut, Oregon, and Washington and the other isolates from California and the remaining states. This finding is consistent with trace forward analyses conducted by the US Department of Agriculture's Animal and Plant Health Inspection Service. At the same time, genetic diversities in several states equaled those observed in California, Oregon, and Washington and two-thirds of multilocus genotypes exhibited limited geographic distributions, indicating that mutation was common during or subsequent to migration. Together, these data suggest that migration, rapid mutation, and genetic drift all play a role in structuring the genetic diversity of P. ramorum in US nurseries. This work demonstrates that fast-evolving genetic markers can be used to examine the evolutionary processes acting on recently introduced pathogens and to infer their putative migration patterns, thus showing promise for the application of forensics to plant pathogens.

New research: Evaluating ornamentals as physical barriers between blocks of plants susceptible to Phytophthora ramorum

2009-10-12T08:23:00.001-07:00

Shishkoff, N. 2009. Evaluating ornamentals as physical barriers between blocks of plants susceptible to Phytophthora ramorum, 2007-2008. Plant Disease Management Reports 3:OT029.

Assessing the potential of Silv-Exﾮ and Silv-Ex Plusﾮ to eradicate Phytophthora ramorum spores in water

2009-10-12T08:21:00.001-07:00

Assessing the potential of Silv-Exﾮ and Silv-Ex Plusﾮ to eradicate Phytophthora ramorum spores in water - Based on two studies at UC Davis, using Silv-Ex® or Silv-Ex Plus® (foaming agent used in fire control) to treat water that is potentially infested with P. ramorum, greatly reduces, but does not eliminate, the concern for inadvertently spreading the pathogen through fire suppression efforts. For more information, contact Kamyar Aram at kamaram@ucdavis.edu.