Hi! Patti, Thank you for posting this. But I am concerned about the Australian bit. Most damage to our hardwood forests is salinity through a rising water table, directly the result of mismanagement and gross over clearing.
The other problem of more limited extent, is "Mundulla Yellows". Scientists are trying to pin it on a "fungus", so far not identified. Careful observation shows that it only occurs where water runs off roads and car parks and away from farm buildings or where motor vehicles are. It would seem to be related to some form of pollution from road transport, but that is too simple for the experts. In Europe, it was observed that "acid Rain" damage in forests did not take place where water from roads made from crushed igneous rock run. Thus a good dusting of Rock Dust would do the trick. It may be worth looking at this in your case. Gil Patti Berg wrote: > THE NEW YORK TIMES > > September 5, 2002 > > Disease Hits Firs and Redwoods, Posing Risk of Economic Damage > > By CAROL KAESUK YOON > > Douglas fir, one of the nation's most economically important timber > species, and California's coast redwood are infected with the > fast-spreading new disease known as sudden oak death syndrome, > scientists reported yesterday. > > The researchers emphasized that they still did not know what impact the > disease would have on the long-term health of redwood and Douglas fir > forests. So far, the disease, which has killed tens of thousands of oak > trees in California, has been found in Douglas fir only in saplings in > Sonoma County. > > But the potential for a major economic impact is already clear. Within a > > few days, regulators said, both species will be added to the official > list > of susceptible species, making these two important trees subject to the > evolving state and federal quarantine regulations intended to stop the > spread of this still poorly understood disease. > > "We were stunned," said Dr. David Rizzo, plant pathologist at the > University of California at Davis who led the study with > Dr. Matteo Garbelotto, a forest pathologist at the Berkeley campus. > "Douglas fir goes up into British Columbia, so this is a big deal." > > Mark Stanley, chairman of the California oak mortality task force, a > coalition of government agencies, nonprofit groups and other private > organizations, said that regulators and task force members hoped to > mitigate the impact on the forestry industry, perhaps by regulating the > movement of only parts of Douglas fir and redwood trees. > > Current federal regulations include the requirement that all host > species harvested from infected areas have all bark removed > and left on site and be accompanied by a certificate before being > transported between states. > > Harvests of Douglas fir, a major timber and Christmas tree species, are > worth more than a billion dollars each year in the United States. > Douglas > fir is the dominant tree of the Pacific Northwest, giving the forests of > > the region their distinctive evergreen canopy. Redwood, also valued as > timber, produces bark that is widely sold for landscaping in gardens. > > In response to the new results, Gov. Gray Davis of California yesterday > sent President Bush a letter requesting $10 million in federal money to > fight the disease. "The implications of this disease are enormous, > including > a major change in the environment and landscape of California, severe > economic dislocation, and an increase in fire danger," the letter said. > > The disease is caused by the microscopic organism known as Phytophthora > ramorum, part of a group funguslike organisms known as water molds. > Discovered in California in 1995, and thought by most scientists to be a > > foreign, invasive species, the disease is a close relative of the > pathogen > that caused Ireland's potato blight and another species that has wiped > out > vast swaths of forest in western Australia. > > Quarantined regions include 12 counties in California and one > nine-square-mile patch in Oregon. > > Researchers found Douglas fir and redwood trees infected with the > pathogen in the wild earlier this year, but they only recently completed > > tests showing that healthy seedlings and saplings could be infected in > the laboratory by the disease. > > Researchers still do not know whether large, mature Douglas fir or > redwood trees can be infected or killed by the disease. > > The symptoms of infected trees of different species range from death, > in oaks, to small spots on leaves in bay trees. It remains to be seen > how > severely Douglas firs and redwoods will react to the infections. In the > field, researchers found that the disease killed the growing branchtips > of > infected, Douglas fir saplings. The disease also killed young sprouts at > > the base of infected redwoods and killed the needles of the tree. > > Meanwhile, as the disease appears to hop from species to species, > infecting a total of 17 known plant species in California so far, > researchers are left scrambling to find ways of containing the > ever-increasing and often unexpected sources of infection, including > yard > and park clippings. > > "The Bay Area alone generates a million tons of green waste a year," Dr. > > Rizzo said. > > Because the disease is thriving there, Dr. Garbelotto said he had been > studying whether composting can be trusted to kill the pathogen or > whether these excesses of yard waste will need careful tracking as well. > > He said he was even working on how to dry bay leaves for cooking so > that they could not spread the disease to other plants. > > No cure is known for the disease, and Dr. Garbelotto and colleagues are > conducting experiments to find possible preventives that can be applied > to a forest. In Australia, where a relative of sudden oak death has > reduced > vast forests to grass and shrublands, managers have found great success > with aerial sprays of preventive chemicals. But researchers say that > sprays > would not be feasible in places like the heavily populated Bay Area or > Muir Woods, a tourist attraction of redwood trees just across the > Golden Gate Bridge. > > "There are more people in Muir Woods on a Saturday afternoon," said Dr. > Rizzo, "than in these sites in a year in Australia." > > In Oregon, the region known to be infected is near Brookings, by the > California border, and only in a species known as the tanoak, one of the > > hardest hit of trees in California. Given the small area, Oregon's > researchers > are actually trying to eradicate the disease from their state by burning > > diseased trees. > > "There's no good precedent for getting rid of a disease like this," said > > Alan Kanaskie, forest pathologist for the Oregon Department of Forestry. > > "If there's a precedent, it's that eradication fails. But maybe we can > at least > delay its spread." > > Copyright The New York Times Company
