Two treatments for P. ramorum infested nursery soil

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

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

From the December COMTF newsletter

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

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

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

Officials shift approach to sudden oak death

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

An Ecological Approach to Sudden Oak Death Prevention

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

Sudden oak death now threatens more of Britain's trees

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

Oregon oak disease fight faces federal aid loss

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

New research on mating hormone for control of P. infestans

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

New nursery research projects at NORS-DUC

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.

Research on SOD at Fort Detrick

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

algae control

Because Phytophthora species are close relatives of brown algae, algae control methods may be useful in reducing water infestation by Phytophthoras. Check out this tip on the WA Adopt-A-Stream website:

"Are you experiencing problems with algae in small lakes or ponds? A recent issue of Organic Gardening magazine (May/June 1999) reported that by using nylon sacks filled with barley straw can severely retard algal growth. The results have been duplicated by British researchers, but thus far, the researchers are unable to explain how and why it works. Organic Gardening recommends practitioners use three ounces of barley straw per square yard of a pond's surface for best results. Wheat straw and corn stalks are also effective, but must by applied at slightly higher concentrations. These methods are both inexpensive and more importantly, are harmless to fish."