Alert: Phytophthora ramorum (Sudden Oak Death)
update for 2006 (February 8, 2007)
In Massachusetts 23 nurseries were included in the
2006 Phytophthora ramorum survey conducted
by the MA Department of Agricultural Resources in
cooperation with the USDA, APHIS Cooperative Agricultural
Pest Survey. The UMass Plant Disease Diagnostic Lab
tested 100 samples from these sites by ELISA and culturing,
and none were positive for P. ramorum. Forty
six states participated in the national Nursery Survey
while Alaska, Iowa, Missouri, and Puerto Rico did
not participate. Wisconsin included P. ramorum
as part of their regular nursery inspection. In total,
4,843 nurseries were visited and 147,347 samples collected.
Sixty two nursery sites in 11 states were confirmed
positive (Alabama, California, Connecticut, Florida,
Georgia, Indiana, Maine, Mississippi, Oregon, Pennsylvania,
and Washington). Two residential sites also had positives.
The United States Forest Service (USFS) has conducted
surveys near nurseries and within the forest environment.
The Massachusetts Department of Conservation and Recreation
worked with USFS to survey nursery perimeters in Massachusetts.
As of October 16, 2006, USFS reported the perimeter
surveys were conducted at 637 nurseries in 29 states.
USFS also reported 366 general forest surveys have
been conducted in 29 states, with 922 samples collected.
In 2007 the USFS will work with its state cooperators
to survey for P.ramorum in waterways.
The damage caused by P.ramorum was first
observed in the 1990s in California when large numbers
of tanoak, coast live oak, and California black oak
were dying off. The cause was not identified until
2002 when researchers compared the Phytophthora
isolated from California trees to the new species,
Phytophthora ramorum, recently described
in European nurseries. P.ramorum has a broad
host range and has the potential to infect many plants
important to the nursery trade and forest areas. Photos
and descriptions of these symptoms and links to further
information on sudden oak death are available at:
For the most up-to-date regulatory information and
a listed of regulated hosts visit the USDA, APHIS
The pest alert is from the Massachusetts Introduced
Pests Outreach Project, a collaborative project between
the Massachusetts Department of Agricultural Resources
and the UMass Extension Agriculture and Landscape
Program aimed at preventing the establishment of new
pathogens and pests in Massachusetts. Visit the project
for more information on Sudden
Oak Death and other
emerging pests or to
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