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["Mark Lee" <markl@nytec.com>]

Blackberry Fungus Enters U.S., Hits Oregon
By RUKMINI CALLIMACHI, Associated Press Writer
Mon Jul 25, 8:54 PM ET
  A deadly fungus used to control the spread of unwanted varieties of
blackberries overseas has landed in the United States, infecting
numerous fields in Oregon, the capital of America's blackberry industry.
  First spotted this spring on the southern Oregon Coast, the rust
fungus has spread to seven counties, according to officials with the
Oregon Department of Agriculture.
  Initially, the species was only spotted on the Himalayan blackberry, a
weed.
  Now it's also been reported in virtually all of the fields of the
commercially grown evergreen blackberry, the No. 2 blackberry crop in
Oregon, accounting for roughly 9 percent of the state's $30 million
blackberry industry.
  The fungus - which prior to its appearance in Oregon had never been
detected in North America - has not attacked the Marionberry, Oregon's
state berry and one of the region's most lucrative berry crops, said
Bruce Pokarney, spokesman for the Oregon Department of Agriculture.
  Officials said it was too early to estimate the potential economic
damage.
  "We're at an early stage with the potential for serious economic
damage, but we're not at the stage where that serious damage has
happened," said Tom Peerbolt, a researcher with the Oregon Raspberry and
Blackberry Commission.
  The fungus has been used since at least the 1990s as a biocontrol
agent to tame the growth of wild blackberries in Australia, New Zealand
and Chile. As recently as last year, the U.S. Department of Agriculture
approached blackberry growers in Oregon to discuss the possibility of
introducing the fungus in the United States to control invasive
varieties of blackberries - but the plan did not move beyond the
discussion stage, said Pokarney.
  Ken Johnson, a professor of botany and plant pathology at Oregon State
University, theorizes that because the evergreen blackberry - which is
not grown commercially in those countries - is native to North America,
it might be more susceptible to the foreign pathogen.
  While all the evergreen blackberry fields appear to have been infected
in Oregon, so far only one grower has reported losing his entire crop.
  "It's appeared in all the Oregon evergreen fields, but it is not at
the stage where it is causing real damage, except at this one site.
Meaning we can find it, it's on the leaves, but the crop is still
intact," said Peerbolt.
  Agriculture officials are meeting this week to begin discussing
possible remedies.
  "The remedy is expensive - spraying," said Johnson.
  "It's a huge problem because it's something that can be battled and
fought, but it takes a pretty rigorous spray program to do that," said
Mark Hurst, owner of Hurst's Berry Farm in Sheridan.
  While the disease has so far only been confirmed in Oregon, scientists
and growers say it's already crossed into southwestern Washington, where
samples taken from several fields are currently being tested for the
fungus.
  Once infected, the leaves of the blackberry bush become stained with a
mosaic of purple spots. Underneath, the foliage is tainted with yellow
pustules.
  "It was brought to my attention today," said Dan Tsugawa, an employee
at his father's Tsugawa Farms in Woodland, Wash. "It's so prolific that
my workers have come out covered in yellow dust."