Sudden Oak Death

SOD research

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 06:46:00 +0000

Help to improve Canada’s evaluation of the phytosanitary risks related to sudden oak death

Description

To better estimate the risk of P. ramorum in eastern Canada, inoculate species such as Quercus rubra, Acer saccharum, Fraxinus americana, Betula alleghaniensis, Abies balsamea and Larix laricina in order to evaluate their susceptibility.
Re-isolate P. ramorum following inoculations.
Assess P. ramorum sporulation following inoculations (see point 2).
Conduct real-time PCR analyses to quantitatively estimate the presence of P. ramorum following inoculations (see point 2).
Study the infection process of this pathogen using a microscope.
Obtain climatic data from locations in Europe where this disease has occurred in order to produce more precise risk models for Canada.

Research team

Simard, Marie
Jinek, Andréa
Bilodeau, Guillaume
Hamelin, Richard
McKenney, Dan

Collaborators

Brière, Stéphan (Canadian Food Inspection Agency)
Watson, Alan ( McGill University)

Danny Rioux

P. ramorum compensation regulations

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 06:36:00 +0000

Compensation Regulations

Phytophthora ramorum (P. ramorum) is the organism that causes Sudden Oak Death (SOD), a serious disease of oaks and other woody and herbaceous plants. Thousands of tan oaks and other oak species have been killed by this disease in California since the mid 1990s. Mortality has also been reported in arbutus, beech, rhododendron, Vaccinium and Viburnum. These plants and others may also exhibit symptoms such as dieback, wilting, and lesions and may play an important role in the spread of the pathogen, both by natural movement in the environment and by the movement of infected plant material via the nursery trade.

SOD has caused great economic hardship for nursery and landscape businesses in those regions where it has become established. For example, in 2001, Canada closed its markets to most plant crops from the states of Oregon and California. Without reopened market access, Oregon nurseries alone faced losses in sales to Canada of $15 to $20 million.

A pest risk assessment was completed by the Plant Health Risk Assessment Unit of the Canadian Food Inspection Agency (CFIA) in March 2002 and was updated in June 2005. This assessment concluded that if P. ramorum were introduced, the disease could have a significant impact on Canada's forest resources and landscape. The pest risk assessment indicates that plants, plant parts, soil and growing media play a role in the movement and dispersal of P. ramorum. Laboratory studies have demonstrated that the disease has the capacity to spread to many oak species, including those growing in Canada. Oak and other related species are a significant component in the Great Lakes-St. Lawrence and Acadian Forest Regions of Canada, are valuable as shade trees in urban areas and parks and are a critical habitat providing food and shelter for wildlife. Wood from oak trees is an important resource for the production of furniture and flooring for use both in Canada and overseas. Rhododendrons, azaleas, camellias, and other ornamental hosts are important landscape plants in Canada and represent a significant portion of the total of the horticulture crops produced. The CFIA Pest Risk Assessment identifies rhododendron, including azalea, Pieris, Viburnum, and Kalmia, as high-risk nursery host plants. Other SOD host species are significant components of forest ecosystems, of commercial forestry seedling nurseries, of small fruit and nut production, and of the lumber industry (both domestic and export).

On March 11, 2004, the United States Department of Agriculture (USDA) informed the CFIA that camellia plants infected with SOD had been found at a nursery in California. The CFIA immediately implemented emergency quarantine measures to prevent the entry of any shipments of plants known to be susceptible to SOD from California. The CFIA also took immediate action to prevent the spread of the disease in Canada, including the quarantine and destruction of imported plants and the sampling of plant material from Canadian nurseries and garden centres that imported and/or received plants from the affected nursery in California.

On March 31, 2004, the CFIA confirmed the presence of P. ramorum in California-origin plant material at nine retail garden centres in the south coastal area of British Columbia. Although this represents a small percentage of all garden centres in British Columbia, if P. ramorum were allowed to spread unimpeded, it would have devastating economic consequences on the entire British Columbia landscape and nursery industry. The value of the nursery and floriculture sectors of British Columbia is estimated at $500 million, with approximately $170 million in export sales to the United States. Additionally, there could be impacts on Canada's conifer log exports to Asian countries. The value of export sales of conifer logs to these markets in 2005 was more than $150 million.

From April to June 2004, a public recall in British Columbia involving the CFIA and the British Columbia Landscape and Nursery Association (BCLNA) resulted in the recovery of approximately 1 400 camellias and identified ten homeowners with infected plants. National survey activities identified an additional five nurseries and three homeowners with infected plants in south coastal British Columbia. Plants that tested positive for P. ramorum and any adjacent host plants were also destroyed.

In 2005, the National (detection) Survey, conducted from June to September, focused on nurseries that had imported host material from California, Oregon and the European Union within the previous six years. At each of these sites, up to 30 samples from plants showing symptoms consistent with P. ramorum infection were collected and submitted for analysis to the CFIA Centre for Plant Quarantine Pests in Ottawa. P. ramorum was not detected during the National Survey, but two sites in British Columbia were found to be positive during the trace-back and trace-forward activities in 2005.

In cases where plants and plant material are found to be infected, the CFIA has issued Notices to affected individuals to eradicate infected plants and plant materials. The intent of the CFIA eradication actions is to prevent the spread of SOD to other areas of the province and Canada and to eventually eliminate the disease in the British Columbia south coastal area.

BC Nursery P. ramorum info, includes letter to homeowners

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 06:23:00 +0000

Managing P. ramorum in BC
'Sudden Oak Death', or 'Ramorum leaf and stem blight' is a disease caused by the fungus Phytophthora ramorum (Pr) that accumulates on host plants (such as Ericaceous plants, which include heathers, azaleas and rhododendrons). This disease is relatively new, only having been identified in the early 1990's in Europe and California. Symptoms of Pr in plants are identifiable, but often, the plants show no symptoms, making diagnosis and monitoring for the disease difficult.

The nursery industry in BC is aggressively working to stop the possible movement of Pr into our part of the Pacific Northwest, in co-operation with the Canadian Food Inspection Agency (CFIA), the BC Ministry of Agriculture and Lands (BCMAL) and other agencies.

Pr is not known to be established in BC. Incidents of Pr in BC have been minimal and sporadic and if found are immediately and rigorously eradicated under the auspices of the CFIA.

In the spring of 2004, thousands of potentially Pr infected camellias were unknowingly distributed across North America. In BC, the industry took up a large scale public recall of possibly infected camellias, and collected and disposed of them safely. This quick action was the only public recall of camellias in North America and minimized the risk of Pr coming into BC.

To further minimize the risk of importing and moving Pr, the BCLNA, with assistance from BCMAL and the CFIA, has developed a Pr Certification Program for nursery growers, silviculture and floriculture industries. This comprehensive program includes mandatory sampling and testing for Pr, workshops for nursery staff, implementation of best management practices and an audit by an independent organization.

For info on pathology, host plants and CFIA regulations, visit the CFIA website.

Download Best Management Practices for Landscapers here...

Download Best Management Practices for Retailers here...

Download a letter for affected homeowners here...

For more information, visit these websites:

California Oak Mortality Task Force:
http://nature.berkeley.edu/comtf/

US Department of Agriculture:
http://www.aphis.usda.gov

United Kingdom Department of Environment, Farm and Rural Affairs:
http://www.defra.gov.uk/planth/pramorum.htm

For detailed information on the P. ramorum Certification program in Canada, visit Canada Nursery (CNLA) website's "Nursery Programs" page.

Canada Nursery P. ramorum info

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 06:21:00 +0000

P. Ramorum (Sudden Oak Death)

P. ramorum, also commonly known as Sudden Oak Death or SOD is a disease that has killed many thousands of oak trees in regions of California. This pathogen has since been found to have a very extensive host range, including nursery plants such as rhododendron, camellia, pyracantha and viburnum. Since it was discovered in California, P. ramorum has also been found in the wild in a relatively small and isolated region of Oregon. P. ramorum has also been found in wholesale nurseries in California, Oregon and Washington and at a small number of wholesale and retail locations in BC. In that province, sites with infected plants are placed under quarantine by the CFIA and infected material has been eradicated.

To prevent the further spread of this pathogen, in 2004 the USDA began to regulate the movement of plants from the three west coast states of CA, OR and WA. Only those nurseries certified as being P. ramoroum-free are ale to ship host plants out of state. As the finds of P. ramorum in BC were limited and considered to be isolated incidents, the CFIA chose to not regulate that province. To further prevent the spread of P. ramorum within Canada, and to provide assurances to their customers of their P. ramorum-free status, most nurseries in BC currently participate in a P. ramorum certification program. This program was developed by the BCLNA and CNLA in cooperation with the Canadian Food Inspection Agency.

Click here for more information on the P. ramorum certification program. Here you will also find further links to related sites.

The impact of Phytophthora ramorum on Canada

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 06:01:00 +0000

To date, neither Sudden Oak Death (SOD) nor its causal agent Phytophthora ramorum has been detected in Canada, despite 2 years of concerted effort by Canadian regulatory and scientific authorities. Nonetheless, economic consequences for Canadian governments and industries can be attributed to the discovery of SOD in California and the subsequent regulatory activities undertaken to protect Canadian resources from this potentially devastating disease.

The Canadian Food Inspection Agency (CFIA), the federal body responsible for phytosanitary issues in Canada, first saw reports of SOD in California in the fall of 1999 and soon after published a pest alert on the disease. Through 2000, as reports of the disease spreading within California grew, so did concern within and outside the United States It was recognized that trade in horticultural and forest products originating in infested areas could spread this disease. In 1999, before any regulatory controls were established for SOD, Canada imported nearly 1.9 million live plants from the State of California, presenting potential pathways for introducing the pathogen to new areas. In light of the possibility that these imports could introduce P. ramorum to Canada with potentially serious consequences, regulatory controls were considered necessary.

In March 2001, Canada imposed import restrictions on commodities deemed to be high risk and originating from areas of the U.S. and Europe known to have the disease. These included all propagative and non-propagative material including nursery stock, logs with bark attached, lumber, bark, mulch, acorns, sawdust, pulpwood, and firewood, of all species of oak (Quercus spp.), tanoak (Lithocarpus spp.), and rhododendron (Rhododendron spp.), as well as soil alone or in association with plant material.

A Canadian pest risk assessment (PRA), completed in the fall of 2001, identified the potential distribution and host range of P. ramorum should it be introduced to Canada, the means by which introduction could occur, and the potential magnitude of the economic and environmental impacts that could result. Limited knowledge about P. ramorum contributed to a high level of uncertainty in the assessment. Nonetheless, the PRA concluded that the potential consequences of introduction were high and that economic loss to both the forestry and horticulture industries and damage to susceptible flora in natural environments could be expected to occur where the organism became established. Potential impacts were estimated to include direct and indirect losses to the horticulture industry through loss of markets and increased costs of production for rhododendrons and other species, and direct and indirect costs to the forest sector through impacts on oaks and maples in particular. Environmental impacts were estimated to be high due to the environmental significance of many of the known host species, particularly effects to understory species in natural forest stands. For example, failure to maintain pest-free status could jeopardize Canada's export trade for rhododendrons, which was valued at $5 million in 2000. The potential losses could be much higher than that if one considers consequential losses to other exports of horticultural stock or wood products and the potential for direct losses to various important domestic resources, including eastern red oaks.

As scientific understanding of the disease has improved, the CFIA has responded by relaxing some import measures such as regulatory controls applying to lumber, sawdust, and fruits. At the same time new hosts have been reported, and these have come under regulatory control over time. At present, Canada regulates the entry of 17 genera, many of which are imported horticultural species. The current version of the regulations may be viewed at: (http://www.inspection.gc.ca/english/plaveg/protect/dir/d-01-01e.shtml ).

These quarantine actions have had economic impacts. Canadian importers and distributors of propagative plant material have found it hard to obtain desired products from some traditional sources as a result of controls or prohibitions applied to some of these commodities. At the same time, significant government resources have been expended in designing and implementing regulations and surveillance activities and in engaging foreign authorities in monitoring exports. These activities in support of Canada's current pest-free status are an integral part of ongoing efforts to combat SOD.

The horticultural nursery industry, particularly in British Columbia, is the key sector being affected by import regulations. The most significant impact to the horticultural sector has been to those commercial nurseries that import retail planting and propagation stock from California or Oregon. Some nurseries estimate that sales of up to $250,000 (Can$) were lost when access to propagative material was restricted by the SOD quarantine. This figure represents 6-7% of the total Canadian nursery farm sales. One retail nursery reported that in 2001 approximately $50,000 (Can$) in sales of indoor palms normally obtained from California was lost as a consequence of the exporting nursery being brought under regulatory prohibitions. In addition, for some nurseries, the total effects of the quarantine will not be felt for several years because propagative material that could not be obtained in 2002 would not have been ready for sale until 2005 or 2006. The opportunity costs of such future impacts will be affected by future trade patterns and value of the Canadian dollar at the time the plants mature and are therefore difficult to quantify.

Trade statistics (Table 1) further demonstrate the significant impact to horticultural revenues as a consequence of SOD quarantines. These figures indicate a 60% drop in imports of regulated commodities whereas unregulated commodities were unaffected. Although other economic factors may have influenced changes in the numbers provided in Table 1, the application of the SOD quarantine had some measurable impact. The prohibition of importation of strawberry plants with soil from California, for example, had an initial impact on strawberry production in Canada that was relieved after the establishment of a certification program that allowed trade to resume.

Table 1 - Quantity of Imports¹

Commodity imported from California	Prior to Canadian SOD Quarantine (1999²)	Following establishment of Canadian SOD Quarantine(2001²)	Following establishment of Canadian Quarantine and introduction of certification approaches to permit some imports (e.g., non-hosts in soil(Jan. - Sept. 2002³)
Rhododendron (a host of SOD prohibited entry to Canada)	$50,300	$19,000	N/A
Strawberry plants for propagation (not a regulated host but exported in soil which was prohibited entry in 2001 but was brought under a certification option in 2002)	$1,020,300	$411,700	$821,600
Cut flowers (no regulatory controls applying)	$8,379,900	$8,545,800	$5,981,600
Plants for cuttings, budding, grafting etc. (no regulatory controls applying)	$22,000	$28,000	$15,000

¹Canadian dollars, ² full year data, ³ Jan-Sept data
Source: Statistics Canada

In addition to the direct impact on industry from market access restrictions, significant financial and human resources have been expended by government departments in developing and implementing regulations. A small part of this was in the actual crafting of the necessary documentation, including the PRA, import policy documents, and publications for public dissemination. A much more significant effort was made in undertaking a national survey to determine whether Phytophthora ramorum was present in Canada. The survey targeted Canadian nurseries that imported potential P. ramorum host material from California, Oregon, and other infested areas from 1997 to 2002 as well as established botanical gardens known to feature susceptible host genera. Plant material from these nurseries and gardens and from known hosts within a 100-meter buffer around such the nurseries was sampled and cultured for diagnostic purposes. The cost of this survey was in excess of $120,000 (Can$).

In summary, while Canada currently remains free of Sudden Oak Death, the mere presence of the pathogen elsewhere in the world has resulted in an estimated domestic economic impact approaching $1 million (Can$). This figure will grow as further trade impacts are felt and as surveys for the disease continue. Although this cost is relatively small compared with the potential costs of introduction of P. ramorum, it is nonetheless substantial to the small businesses that rely on uninterrupted trade and that are the most affected by current quarantine measures. As our scientific understanding of this disease improves, regulatory responses will evolve that provide necessary phytosanitary protection with minimal impact on trade.

see article here

Eric Allen ¹, Brenda Callan ¹, Lesley Cree ², Shane Sela ³,
¹Natural Resources Canada, Canadian Forest Service, Victoria, British Columbia, Canada.
²Canadian Food Inspection Agency, Plant Health Risk Assessment, Ottawa, Ontario, Canada.
³ Canadian Food Inspection Agency, Plant Health, Victoria, British Columbia, Canada.

Potential for SOD spread in BC

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 05:59:00 +0000

Potential for disease spread to BC

Strict regulatory controls are in place in California, Oregon, and Washington to prevent the spread of P. ramorum, and Canadian quarantine regulations have been established to help prevent the introduction of the disease into Canada on nursery stock, soil or other host materials.

There is a high risk that Ramorum blight and dieback will have a serious impact on BC's horticulture sector and environment, due to its wide host range and the presence of a suitable climate. The introduction of this disease and its subsequent spread could threaten the ornamental and berry industries as well as many native plants. Prevention of its introduction and rapid eradication efforts, should the disease be introduced, are key to protect these industries from losses caused by P. ramorum.

How can you prevent the introduction of this disease into BC?

To help prevent the introduction of P. ramorum, do not transport infected or potentially infected host material and soil that are taken from areas where the pathogen is known to occur. Contact the Canadian Food Inspection Agency's (CFIA) local office regarding quarantine restriction information on movement of hosts and associated materials. Be aware of the symptoms, visually inspect host plants, and report possible cases to your local office of the CFIA, Canadian Forestry Service (CFS), or Ministry of Agriculture & Lands (MAL).

The Canadian Nursery and Landscape Association (CNLA) has developed a comprehensive certification program for commercial nurseries. The program was launched in the fall of 2004 and it annually certifies more than 250 nurseries in BC. The key components of the program are annual nursery sampling and testing for P. ramorum, implementation of best management practices, and independent third-party audits to ensure nursery compliance. The program reduces the risk of P. ramorum being introduced and/or established at a nursery and, thereby, protects the garden centres and landscapers that purchase planting stock from the nursery.

Control

Preventing the introduction and spread of P. ramorum is the key to minimize the impact on the nursery and environment.
Commercial nurseries are advised to adopt the recommended Best Management Practices (BMPs) and the Phytophthora ramorum Nursery Certification Program to safeguard the industry.
Fosetyl-AL (Chipco Aliette T&O) and metalaxyl (Subdue MAXX) have gained emergency registration for preventative use in nurseries and landscape plantings.
Scout for visible symptoms, particularly during spring, early summer and fall when the pathogen is active. If suspected, immediately notify the local office of the CFIA, CFS, or MAL.

Quarantines have been put in place in both California and Oregon to limit the spread of the disease, and eradication is underway in Oregon. As a rule, these regulations pertain to nursery plants of known hosts or their close relatives, wood products and soil. An import policy D-01-01 titled, "Phytosanitary Requirements to Prevent the Entry of Phytophthora ramorum" has been implemented to prevent the introduction of sudden oak death into Canada (CFIA – revised Oct. 18/2005). The regulations may be viewed at http://www.inspection.gc.ca/english/plaveg/protect/dir/d-01-01e.shtml

Detection and Identification

In BC, disease and pathogen identification services can be obtained by submitting suspicious samples to the BCMAL Plant Diagnostic Laboratory in Abbotsford, or to the Pacific Forestry Centre Laboratory in Victoria.

Further Information

see http://www.agf.gov.bc.ca/cropprot/sod.htm

Ministry Contacts:

Siva Sabaratnam, Ph.D.
Plant Pathologist
Food Safety & Quality Branch
Tel: 604 556-3029

Dave Woodske
Industry Specialist, Ornamentals
Industry Competitiveness Branch
Tel: 604 556-3044

Sudden Oak Death in BC?

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 05:50:00 +0000

Check out OakMapper for up to date maps of P. ramorum

I wish I could find refs for incidence reports.... the map indicates SOD in Nanaimo - can anyone confirm this?

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Gardenwise: Minimizing the Risk of SOD

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 05:49:00 +0000

Sudden Oak Death is a new disease caused by Phytophthora ramorum, a fungus-like pathogen that has killed tens of thousands of oak trees in California and is known to affect and sometimes kill other nursery plants. It was identified in the mid-1990s and scientists and nurseries are doing all they can to learn more about the disease and how to fight it.

P. ramorum is extremely difficult to identify as its symptoms are common to many plant disorders, including other diseases and non-living factors. For example, sunburn is one disorder that can be confused with P. ramorum. DNA testing is required for disease verification. P. ramorum is spread by water splash and its spores may remain dormant in the soil for several years, making it difficult to find and eradicate.

Approximately 52 plant genera have been identified as possible hosts of this plant disease. In some plants it is deadly, in many it may be nothing more than a few dots on a leaf. As science catches up, we will learn better ways to diagnose the disease and determine its effect on the ecosystem and our gardens.

The most susceptible plants appear to be broadleaved evergreens such as camellias, viburnum, rhododendrons, pieris and kalmia. Syringa (lilac) is also a concern because it encourages the disease to produce spores.

Camellia recall
In spring 2004, shipments of camellias from one California nursery – some of which were infected with P. ramorum – were sent to garden centres across North America. British Columbia was the only region to launch a public recall in a bid to prevent the disease from spreading into the urban or natural environment.

Trained inspectors were sent throughout the Lower Mainland and Vancouver Island to check the plants of homeowners who purchased camellias. Suspect plants were sampled, then destroyed. Less than one per cent tested positive for P. ramorum. Locations with positives are tested regularly until the Canadian Food Inspection Agency (CFIA) is convinced the disease has been controlled.

The camellia recall was a success because of team work. The CFIA ensured the program met its standards, the BC Ministry of Agriculture and Lands provided technical support, media ensured the public was aware of the recall and the BC Landscape & Nursery Association managed the process.

Status of P. ramorum in Canada and US
The Canadian Food Inspection Agency surveys Canadian nurseries annually, looking for new and other ‘quarantineable’ diseases, including P. ramorum. In 2003, P. ramorum was identified in B.C. at one wholesale nursery; in 2004, new finds were identified at three nurseries and several garden retailers. In 2005, positives were found at one wholesale nursery and a few garden retailers, all in the Lower Mainland or on Vancouver Island. The CFIA takes aggressive action to eradicate the disease when it is found, including site quarantine, destroying infected and adjacent plants, and sanitizing and monitoring the site for several years.

CFIA traces potentially infected plants from place of origin to final location, and as a result, have found P. ramorum-infected plants at a few landscape projects. Their normal stringent measures are carried out.

In 2005, the United States recorded 55 positive sites in seven states. Most were in the three regulated states of California, Oregon and Washington, but a few were found in Georgia, Louisiana, Tennessee and South Carolina.

B.C. minimizes risk of disease
The BCLNA has developed a P. ramorum nursery certification program to minimize the risk of Canadian or US nurseries receiving or spreading P. ramorum. The program includes plant sampling and testing; mandatory training; implementation of best management practices and an annual audit to ensure procedures are being followed. Over 300 B.C. growers are voluntarily participating in the program, which is under review as a model for other jurisdictions in North America.

Assistance in developing the P. ramorum program was provided by the CFIA, Agriculture and Agri-Food Canada, the BC Ministry of Agriculture and Lands, Canadian Nursery Landscape Association, Investment Agriculture Foundation, and the BCLNA’s Industry Development Council.

For more information on P. ramorum:
Industry: www.CanadaNursery.com
Click on Nursery Programs and scroll through the two P. ramorum and Canadian Nursery Certification Institute sections in the sidebar.
CFIA: www.inspection.gc.ca/english/plaveg/protect/pestrava/sodmsc/sodmsce.shtm...
California: www.suddenoakdeath.org

Sudden Oak Death in the Gary Oak Ecosystem

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 05:23:00 +0000

Since 1995, large numbers (up to 80% in some areas) of tanoaks (Lithocarpus densiflorus), coast live oaks (Quercus agrifolia) and black oaks (Quercus kelloggii) have been dying in California’s coastal counties. The epidemic, referred to as Sudden Oak Death (SOD), was first seen on tanoak in Mill Valley (Marin County) in 1995. Since then, it has spread north into ten central coastal counties of California and Curry County, Oregon. In 2003 the disease was also found for the first time in nurseries in British Columbia, California, Oregon, and Washington.

In June 2000, University of California researchers isolated a previously unknown species of Phytophthora (“Phy-TOFF-thoruh”), a fungus-like organism, from dying oak trees. Relatives of this “fungus” caused the Irish potato famine, Port-Orford cedar root disease in the Pacific Northwest and are causing oak dieback in many parts of the world. In January 2001 researchers reported that a new species of Phytophthora isolated as early as 1993 from ornamental rhododendrons in Germany and The Netherlands matches the newly discovered species found in California. This new species has since been officially named: Phytophthora ramorum. The name refers to the pathogen’s tendency to cause infection on branches.

Important research discoveries have continued since then. So far, Garry oaks haven’t been affected by SOD. Researchers also found that the plants most prone to the disease include several other oak species, blueberries, honeysuckle, huckleberry, rhododendrons, azaleas, viburnum, pieris, and camellia. Some species of Douglas-fir, arbutus, sumac, and maple are also at risk. Scientists determined that Phytophthora ramorum may be spread through infected wood, soil and rainwater. However, probably the most important way in which humans spread the pathogen around is by moving infected plants and plant parts. The leaves of hosts such as bays, madrones and rhododendrons contain large amounts of spores, which may be dispersed through the air under moist and windy conditions.

For more information on sudden oak death, visit the following web sites:

Canadian Food Inspection Agency
Canadian Nursery Landscape Association
Oregon Department of Agriculture
California Oak Mortality Task Force
University of California Cooperative Extension in Marin County
USDA Forest Service (Sudden Oak Death - A guide for forest managers, Christmas tree growers, and forest-tree nursery operators in Oregon and Washington)

BC is now free of Sudden Oak Death

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 05:20:00 +0000

It seems overly optimistic to say we are free of the disease...! This article was in the VAncouver Sun a few weeks ago (link at bottom)
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The first case of the deadly fungal disease known as sudden oak death surfaced in a Richmond nursery in June, 2003.

Phytophthora ramorum was found on a single rhododendron at the nursery, which was not named by the investigating Canadian Food Inspection Agency.
The infected plant was thought to have come from a U.S. nursery on imported stock.
In California, sudden oak death has been responsible for the rapid decline and death of up to 80 per cent of oak and tanoaks in certain areas.
The disease is rampant in some European countries, notably the Netherlands and Germany, and outbreaks have been reported in Britain.
In April, 2004, thousands of plants imported to B.C. from California were destroyed or quarantined after it was discovered that they were infected with the lethal pathogen.
The disease entered B.C. in a shipment of 3,000 camellias imported from Monrovia Nursery in southern California, one of the biggest nurseries in North America.
Checks have since been put in place to ensure that all nursery stock is carefully tested before it is imported and that any outbreak in carefully quarantined to prevent it spreading.

Here's what we do know about the disease:
- Sudden oak death (Phytophthora ramorum) is a relatively new pathogen, first identified through DNA testing 20 years ago. It is part of the same family of fungal diseases as the late-blight that affects potatoes and tomatoes, turning them to mush at the end of summer. The North American and European strains are slightly different, affecting a slightly different range of host plants. The two strains are thought to have evolved separately.
- At least 40 species have been identified as prone to the disease. They include oak, rhododendron, Douglas fir, beech, laurel, lilacs, camellia, yew, viburnum, grand fir, Japanese maples, redwood, kalmia, leucothoe, arctostaphylos, arbutus, pieris, and vaccinum.
- The disease causes leaf spots, bleeding cankers and dieback that ultimately results in the plant's decline and death. Cankers produce a sticky, reddish-brown to tar-black ooze that has a wine-like smell. These occur mostly in the lower three metres of the trunk of a tree. As the disease develops, foliage changes rapidly from a healthy green to chlorotic yellow and finally brown. In oaks, decline can happen within weeks or months, which is why the pathogen is called "sudden" oak death.
- Sudden oak death is believed to have been introduced to the San Francisco area of California in 1989. No one is sure where it came from. Over the last decade, it is responsible for the decline and death of up to 80 per cent of oaks and tanoaks in certain areas.
- From California, the disease quickly spread to Oregon in the 1990s.
- While scientists do not expect SOD to cause destruction on the scale of chestnut blight or Dutch elm disease, they are alarmed by its ability to adapt to different climatic conditions.
- In Europe, the disease has spread to parts of Britain, Germany, the Netherlands, Spain, Ireland, Poland and France. In Britain, where the pathogen has been identified at more than 320 nurseries, host plants are slightly different: experts there also list buddleia, vine maple (Acer circinatum), salal (Gaultheria shallon), Clematis montana, California lilac (Ceanothus), and witch hazel.
- A wide variety of plants have been inoculated in Europe with the disease to see how they react. The popular Exbury azaleas and Rhododendron ponticum were discovered to be extremely susceptible while evergreen azaleas have shown greater tolerance. R. ponticum developed severe leaf and stem lesion after one week while European beech (Fagus sylvatica), and American red oak (Quercus rubra) showed severe dieback of twigs after four weeks. Lime hornbeams, poplar, elm, and ash trees were all found to be resistant.

Please see the whole article here

Pathogen Outbreak Plagues Trees in Park

noreply@blogger.com (Elisa) — Mon, 05 Jan 2009 05:07:00 +0000

....Brice McPherson, research associate at the Center for Forestry on campus, noticed a particularly large outbreak of the disease in October 2006. Approximately 20 percent of the oaks in the park are affected.

The researchers, working with a $50,000 grant from East Bay Regional Parks that they obtained in August, began to study the Tilden oaks in November. So far, they have found the disease in every group of oaks they have inspected.

"Basically, the pathogen is a naturalized citizen of California," McPherson said. "It's everywhere within the forests where it has become established."

According to McPherson, the disease is caused when spores of a pathogenic water mold enter the tree's outer bark and attack the nutrient-conducting phloem tissue. The process attracts beetles that tunnel into the tree-the final cause of its death.

During its slow decay, which typically lasts two to five years, the infected oak oozes sap that resembles human blood from large cankers at its base, he said.

But what passers-by notice is the leaves' sudden change from green to brown immediately preceding the tree's death. For other plants, the disease has less severe effects.

"Most of the woody plants you see in Northern California are hosts for this pathogen, but for most, it is just a minor annoyance," McPherson said.

Outbreaks of Sudden Oak Death now plague Oregon, Washington, and British Columbia. All Bay Area counties are quarantine areas for the disease.

"We're trying to draw a line in the sand to stop the movement north," said Ronnie Eaton, deputy agricultural commissioner for Alameda County's Agricultural Commissioner's Office.

The commissioners inspect potential host plants before nurseries ship them outside the quarantine area and regulate the movement of susceptible plants and goods, like oak used for firewood.

Visitors of areas with high rates of infection are advised to clean their muddy shoes before leaving, Eaton said.

The water-borne pathogen also easily travels through streams, fog and wind, making containment of the disease difficult and posing serious problems for ecosystems.

"Our forests here have so many fewer tree species (than the East Coast), that the loss of oaks and tan oaks may lead to much more severe ecological impacts," McPherson stated in an e-mail.

He said many organisms depend on the oaks' acorns, since there are few other sources of high-quality plant protein.

While Oregon has used the slash-and-burn method to destroy areas where Sudden Oak Death has taken root, the problem's magnitude in California has precluded similar efforts.

"No one is under any eradication program whatsoever. It's just too far spread," said Joe Deviney, deputy agriculture commissioner for Contra Costa Country, which has jurisdiction over Tilden Park.

McPherson said it can be disheartening to study a disease with no apparent solution, but the work is still important.

"I don't really imagine there's anything anyone can do at this point," he said. "It's something we're going to have to come to terms with."

Please see the whole article here

Making Willow Water and SAR

noreply@blogger.com (Elisa) — Fri, 27 Jun 2008 01:24:00 +0000

Making Willow Water and SAR

Plants make salicylic acid to trigger natural defenses against bacteria, fungi, and viruses. Aspirin thus is an activator of ‘Systemic Acquired Resistance’ (SAR). However, plants often don’t produce the acid quickly enough to prevent injury when attacked by a microbe. Spraying aspirin on the plants speeds up the SAR response. Tests have shown this works on many crops, producing better plants using less pesticide. “It also makes it possible to successfully grow many fine heirloom varieties which were discarded because they lacked disease resistance.” Powell says.

Scientists first encountered the SAR phenomenon in the 1930s. After encountering a pathogen, plants use salicylic acid as a key regulator of SAR and expression of defense genes. “Only recently have companies begun marketing salicylic acid and similar compounds as a way to activate SAR in crops—tomato, spinach, lettuce, and tobacco among them,” according to Powell.

“ARS scientists are studying plants’ defenses, such as antimicrobial materials like the protein chitinase which degrades the cell walls of fungi, and nuclease enzymes which break up the ribonucleic acid of viruses. They’re also testing aspirin and other SAR activators which could be effective against non-microbial pests such as aphids and root-knot nematodes,” Powell says. “This may be the most important research of the century. Stimulating SAR defenses with aspirin or other activator compounds could result in increased food production and the elimination of synthetic pesticides.”

He recommends we experiment by spraying some plants with a 1:10,000 solution (3 aspirins dissolved in 4 gallons of water), leaving other plants unsprayed. Tests have shown that the SAR activation lasts for weeks to months. (Sort of homeopathic heart attack prevention for your plants.)

Here are links to more info on aspirin for plants

they also said it improved seed germination.

for roses - they also use h2o2

using willow
plant headaches

Two strains of pathogen

noreply@blogger.com (Elisa) — Fri, 27 Jun 2008 01:22:00 +0000

Two strains of pathogen found

The American strain of sudden oak death was found for the first time in 1995 in Mill Valley, California. Since then, it has been detected in 17 California counties. And in 2001, it was found in Curry County, Oregon near the California border.

The disease has killed thousands of oak and tanoak trees found in California and Oregon. Other plants common to the Pacific Northwest are susceptible to the disease, but are not likely to die.

Since May 2003, the European strain of sudden oak death has been detected in nurseries in Oregon, Washington and British Columbia, Canada, although most infected plants are by the American strain. There is no evidence that either strain has moved beyond the nursery environment.

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The origin of sudden oak death is unknown

Plant pathologists do not know where the pathogen originated, but the disease is spread naturally and artificially. In nature, the pathogen is spread through the movement of water in the form of rain, mist, dew and runoff. Humans spread the disease through the movement of infected nursery stock and possibly with firewood and soil on the bottoms of shoes and boots. (Although viable spores have been detected on boots there is no evidence that the pathogen is spread this way.)

No pesticide to control sudden oak death

There is no pesticide registered by the U.S. Environmental Protection Agency that will eradicate the organism that causes sudden oak death. The only way to stop the disease is to cut down and burn infected plants or trees.

SOD Pest Risk Assesment

noreply@blogger.com (Elisa) — Fri, 27 Jun 2008 01:06:00 +0000

from canadanursery.com

"...Tree mortality of both live and tan oak has been confined to the coastal fog belt and in association with bay laurel. ...
P. ramorum is considered to be a nursery disease and while many plant species can be infested with P. ramorum, only a few are capable of spreading the disease. These include Rhododendron, Camillia, Kalmia, Viburnum and Pieris. ...

CFIA have proposed regulating only the five high-risk host plants at the genus level with all other plants will be regulated at the species level, in harmony with USDA regulations. Changes have also been made to the P. ramorum infested nursery protocol to reflect the lower risk status of the disease. Industry is invited to comment on both; they can be downloaded from the CNLA website"

Phylogeny of Stramenopiles

noreply@blogger.com (Elisa) — Fri, 27 Jun 2008 00:41:00 +0000

Stramenopiles

from TOLWEB:

This grouping of protists arose largely from molecular studies which categorically confirmed that algae (previously referred to as Heterokonts or Chrysophytes) were related to a variety of non algal protists - such as the heterotrophic bicosoecid flagellates and the fungal oomycetes (Leipe et al, 1994). The group was informally named by Patterson (1989) and was based at that time on cytological evidence.
The hairs which define this group are a distinctive subset of hairs encountered in protists, and are distinguished by having a long hollow shaft that gives rise to a small number of fine hairs, and the entire structure inserts into the cell by a basal region. These hairs usually occur on the flagella. A number of supposed stramenopiles are thought (opalines) or known (diatoms) to have lost the hairs. The stramenopiles is a very major grouping of eukaryotes containing some organisms with the largest linear dimensions known in the eukaryotic world (brown algae), as well as ecologically very important organisms - such as the diatoms.
Characteristics
Tubulocristate protists with tripartite tubular hairs or derived from such organisms.

References

Leipe, D.D., Wainright, P.O., Gunderson, J.H., Porter, D., Patterson, D.J.,Valois, F., Himmerich, S. and Sogin, M.L. (1994): The stramenopiles from a molecular perspective: 16S-like rRNA sequences from Labyrinthuloides minuta and Cafeteria roenbergensis. Phycologia. 33:369-377.

Patterson, D.J. (1989): Stramenopiles: chromophytes from a protistan perspective. In: Green J.C., Leadbeater B.S.C. and diver W.L. (eds): The chromophyte algae problems and perspectives, pp. 357-379. Clarendon Press, Oxford.

Sogin, Mitchell L. and Patterson, David J. 1995. Stramenopiles. Version 01 January 1995 (under construction). http://tolweb.org/Stramenopiles/2380/1995.01.01 in The Tree of Life Web Project, http://tolweb.org/

Sudden Oak Death (SOD) in the San Francisco Bay Area

noreply@blogger.com (Elisa) — Wed, 25 Jun 2008 23:55:00 +0000

This program examines the disease Sudden Oak Death (SOD) which is attacking oaks and now other trees and plants in the San Francisco Bay Area. Program shows the symptoms of SOD on oaks, explains the cause of the disease, and outlines steps people can take to help slow its spread. Includes interviews with UC horticulturist Pavel Svihra who discovered and named this disease, UC Davis plant pathologist David Rizzo who discovered the pathogen responsible, and Forester Kent Julin of the Marin County Fire Dept. who discusses the fire danger associated with dead and dying trees. Series: "University of California Division of Agriculture and Natural Resources" [8/2001] [Science] [Agriculture] [Show ID: 5929]

Phytopthora ramorum zoospores emerging on YouTube

noreply@blogger.com (Elisa) — Wed, 25 Jun 2008 23:52:00 +0000

Sudden Oak Death Fungus May Be Lurking In Your Shrubbery

noreply@blogger.com (Elisa) — Wed, 25 Jun 2008 22:56:00 +0000

Symptoms:

Camellia

Viburnum

(Note: hole punches in leaves were made to remove leaf disks for analysis for Phytophthora ramorum the cause of Sudden Oak Death.)

Rhododendron

excerpt from NCSU Plant Pathology, please click for entire article:
(I added the bold for emphasis, below)

"Although Sudden Oak Death (SOD) is a forest disease, the organism that causes this disease is capable of infecting a large number of woody ornamental plants that are commonly sold by nurseries and planted into urban landscapes.

Background:

Despite the name, Sudden Oak Death disease is not just restricted to oaks.

Camellias, rhododendrons, Pieris, mountain laurel, viburnum, and lilacs are among 60 different plant hosts or potential carriers of the disease.

Only above ground plant parts are affected. The roots of infected plants remain healthy.

On oaks, the organism causes bleeding cankers on the trunk that can eventually girdle and kill the tree. On the majority of host plants, however, the disease causes leaf spots and twig dieback, but very rarely results in plant death.

Infected oak and tan oak trees in California forests are typically found in close proximity to other host plants such as bay laurel that have infected leaves. As such, it would be unusual to have an infected oak tree with a bleeding canker without the presence of other nearby foliar plant hosts such as mountain laurel or camellias. The disease is not known to spread from oak to oak."

P. ramorum Infection of Rhododendron

noreply@blogger.com (Elisa) — Wed, 25 Jun 2008 21:09:00 +0000

Image from Northeast Plant Diagnostic:
Image from Institute for Agricultural and Fisheries Research(Netherlands)

Phytopthora ramorum lifecycle

noreply@blogger.com (Elisa) — Wed, 25 Jun 2008 21:04:00 +0000

Image from the WSU SOD program

Sudden Oak Death

noreply@blogger.com (Elisa) — Wed, 25 Jun 2008 20:46:00 +0000

I may be starting a new job working with the pathogen that causes "Sudden Oak Death", so I created this blog to help me organize links and information as I learn about this subject!

some links to get me started:

I live in Canada, so I looked at the Canadian Phytopathology Society (CPS) site: Sudden Oak Death

Lots of news and information about SOD in Canada there.

Also the CFIA website...

on the APSnet: Sudden Oak Death Online Symposium with great list of online resources

Google of Sudden Oak Death, Google of ramorum, Wiki entry

External links from Wiki:

http://www.suddenoakdeath.org

New Scientist news

University of California SOD pest notes

California Agriculture

UK Department of Environment, Food and Rural Affairs - notes on SOD

Washington State University SOD Resources

Reducing spread of SOD

Pocket Diagnostic Test Kits

I guess that's enough for now.....