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A38 trees in Devon cleared to slow disease

BBC News 8 November 2011

About 2,100 trees will be felled in south Devon in a bid to slow the spread of an "aggressive virus", the Highways Agency has said.

Trees will be felled along the A38 between Exeter and Plymouth from the middle of November, it added.

The Forestry Commission said the disease, called Phytophthora ramorum, had spread to some of the trees, and felling would help to control it.

Trees will be felled at 29 sites, including Haldon Hill and Marley Head.

About 100 hectares of infected trees in the Glynn Valley, in Cornwall, have already been felled.

The Forestry Commission has served the Highways Agency with a Plant Health Order to fell the trees along the A38 before the end of March 2012.

'No chemical treatments'    more....
Urban tree disease found in England

UK Forestry Commission

October 19, 2011

A deadly plant disease previously unknown in England has been found in Devon killing Lawson Cypress trees that are commonly found in parks and gardens.

Forestry Commission scientists have confirmed that Phytophthora lateralis, a fungus-like pathogen that kills trees’ roots, has infected several trees in a shelter hedge on an industrial estate.

The disease is very infectious to Lawson Cypress and some other trees, but harmless to people, animals and most other plants. The trees will be felled and disposed of safely and the site is subject to biosecurity measures to prevent spreading the disease particularly in contaminated soil, felling equipment and other tools. 

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Wet spring caused jump in sudden oak disease: Survey results show Skyline area hit hard by forest pathogen

Santa Cruz Sentinel
Posted: 10/17/2011
 
SUMMIT — A deadly disease attacking trees in California's coastal forests has reached “epidemic” levels along the ridge separating Santa Cruz and Santa Clara counties and is spreading in the San Francisco Bay Area.

The sudden oak death findings are the result of a survey conducted last spring by specially trained citizen volunteers.

Nearly all the samples gathered along southern Skyline Boulevard tested positive for the pathogen that has killed hundreds of thousands of native oaks and tanoaks in California, according to the results released this month.

“Such a high percentage in that area right at the edges of the county certainly indicates a total epidemic state of disease,” said Matteo Garbelotto, who heads up UC Berkeley's Forest Pathology and Mycology Laboratory. “We didn't expect something at that level.”

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The Christmas Tree Curse - Ho ho ho and an incurable pathogen

Sierra Magazine Nov/Dec 2011

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.

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Hundreds of diseased trees to be felled on Isle of Man

BBC News 4 October 2011

Hundreds of trees are to be felled in two plantations on the Isle of Man after a pathogen which causes a deadly disease was discovered.

Phytophthora ramorum was found by the Forestry Commission last month when they carried out aerial surveys of the island's plantations.

More than 9,000 cubic metres (317,832 cubic feet) of trees will be felled in Colden and Ballaugh.

The work will begin in Colden, near Baldwin, on 8 October.

Phytophthora ramorum, a fungus-like pathogen, causes the ramorum disease which is is particularly serious in Japanese larch trees and rhododendrons.

Walkers and cyclists will have no access to the Colden plantation while the work is carried out and only limited access to Ballaugh until the work is completed in April 2012.

Aerial surveys by the Forestry Commission showed the affected areas

Aerial surveys by the Forestry Commission showed the affected areas

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Oregon officials find new cases of sudden oak death six miles north of quarantine zone

The Oregonian Friday, September 30, 2011, 3:55 PM     Updated: Saturday, October 01, 2011, 7:25 AM

Oregon forestry officials were alarmed last week to find trees infected by sudden oak death in Curry County more than six miles north of the 162-square-mile quarantine zone established to keep the deadly fungal disease from spreading outside southwest Oregon.

“It has big implications,” said Alan Kanaskie, forest pathologist with Oregon Department of Forestry. He said the new outbreak is more than 12 miles from the nearest known infected tree – the longest distance that scientists have seen Phytophthora ramorum travel since the battle to contain the disease in Oregon began a decade ago.
 
"We want to make sure it doesn't spread farther," he said. "Our goal since last year is to keep it in a small box near Brookings."

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Colourful allure of sudden oak death

 

New Scientist blog, September 9, 2011

Sudden oak death doesn't sound pretty but snap it with the right camera, from the right angle, and it can look alluring.

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New Disease Reports 2011

First report of Phytophthora cinnamomi associated with stem cankers of Quercus cerris in South Africa

E. Oh, B.D. Wingfield, M.J. Wingfield and J. Roux

New Disease Reports (2011) 24, 11. [http://dx.doi.org/10.5197/j.2044-0588.2011.024.011]

Quercus cerris (Turkey oak) is native to the orient and southeastern Europe (Balci & Halmschlager, 2003a). These trees are also commonly planted as non-native ornamentals in countries including South Africa. Recently, bleeding cankers on the stems, typical of Phytophthora infection, were found on Q. cerris trees growing on the Vergelegen Estate near Somerset West in the Western Cape Province of South Africa (Fig. 1). Phytophthora species have been recognised as being involved in the decline of Quercus spp., including Q. cerris, in eastern and north-central USA and Europe (Balci et al., 2007). Species isolated from soil associated with declining Q. cerris include P. citricola, P. cryptogea, P. quercina, and P. syringae (Balci & Halmschlager, 2003a,b), while P. ramorum and P. cinnamomi have been isolated directly from sapwood of trees showing bleeding cankers in Europe (Brown & Brasier, 2007).

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Plant Pathology Early View article 24 Aug, 2011

Infectivity and sporulation potential of Phytophthora kernoviae to select North American native plants
E. J. Fichtner, D. M. Rizzo, S. A. Kirk, J. F. Webber

Phytophthora kernoviae exhibits comparable epidemiology to Phytophthora ramorum in invaded UK woodlands. Because both pathogens have an overlapping geographic range in the UK and often concurrently invade the same site, it is speculated that P. kernoviae may also invade North American (NA) forests threatened by P. ramorum, the cause of Sudden Oak Death. This paper addresses the susceptibility of select NA plants to P. kernoviae, including measures of disease incidence and severity on wounded and unwounded foliage. The potential for pathogen transmission and survival was investigated by assessing sporangia and oospore production in infected tissues. Detached leaves of Rhododendron macrophyllum, Rhododendron occidentale and Umbellularia californica, and excised roots of U. californica and R. occidentale were inoculated with P. kernoviae and percent lesion area was determined after 6 days. Leaves were then surface sterilized and misted to stimulate sporulation and after 24 h sporangia production was assessed. The incidence of symptomless infections and sporulation were recorded. All NA native plants tested were susceptible to P. kernoviae and supported sporangia production; roots of U. californica and R. occidentale were both susceptible to P. kernoviae and supported sporangia production. Oospore production was also observed in U. californica roots. The results highlight the vulnerability of select NA native plants to infection by P. kernoviae, suggest that symptomless infections may thwart pathogen detection, and underscore the importance of implementing a proactive and adaptive biosecurity plan.
Critically endangered species translocated (P. cinnamomi)

22 August 2011  Thirteen critically endangered plant species in WA’s Midwest and South Coast have successfully gone through translocation over the past year, with survival rates now ranging from 50–90 per cent, according to the Department of Environment and Conservation (DEC).

Translocation is the reintroduction of plants, animals or habitats from one location to another.

DEC research scientist Rebecca Dillon says translocations have been one of the most successful management actions to prevent extinction of critically endangered plants.

 

More at - Science Network Western Australia

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