UC IPM Makes It Happen
IPM Advisor coordinates worker protection safety training in Kern County
High levels of pesticide exposure incidents in Kern and other
southern San Joaquin Valley counties prompted the U.S. Environmental
Agency (EPA) to award a $50,000, two-year grant to UC IPM Advisor
David Haviland to provide worker protection training to farmers and
workers in Kern County.
Primarily, these incidents have been the result of drift from ground
and aerial applications of insecticides or the off-site movement
of fumigants.The project is a collaborative effort of the Kern County
UCCE, Kern County Agricultural Commissioner's office, and the UC
Statewide IPM Program.
The U.S. EPA grant provides funding toward two major
education programs. The first program is co-funded through the
office and offers a series of 20 meetings for private applicators
in Kern County. Training sessions are held at several locations
and focus on the responsibilities of private applicators for the
safety of field workers on their properties.
The second objective
of the project is to provide a train-the-trainer program for
farm labor contractors in the southern San Joaquin
Valley. This program will follow the training model developed
by the UC IPM
Pesticide Safety and Education Program, an innovative outreach
program from 1987
This coordinated effort among federal, state, and county agencies
and the university promises to help reduce the number of pesticide
incidents in the southern San Joaquin Valley, as well as increase
farm worker safety throughout the region.
Herbicide-resistant horseweed found in the south Central Valley
Anil Shrestha, UC IPM weed ecologist, and Kurt
Hembree, UCCE weed management
farm advisor, both based in Fresno County, have confirmed the existence
of a glyphosate-resistant horseweed biotype in the south Central
Valley. This is the first confirmation of glyphosate-resistant
horseweed in California.
Glyphosate is the active ingredient in several
for use in California. The most common brand is Roundup. According
to the California Department of Pesticide Regulation, 5.7 million
of glyphosate were used by the agricultural industry in 2003.
collected horseweed seeds from the canal banks of an irrigation district
in Dinuba and from western Fresno. They
these two sites and tested for glyphosate-resistance at the
UC Kearney Research and Extension Center greenhouse. The weed seeds
in pots and treated with three rates (1, 2, and 4 lb a.i./acre)
of glyphosate at five different growth stages. Generally, the
weeds from west Fresno
died when exposed to the 1 lb a.i./acre rate, whereas the seedlings
and plants from the Dinuba area survived a glyphosate application
up to 4 lb a.i./acre.
"The irrigation district had been continuously using glyphosate
alone for weed control on the canal banks for about 15 years," says Anil. "This
continuous use of the same herbicide group may have caused the
resistant biotype of horseweed to evolve over the years."
help growers combat this weed, which has become more widespread,
Anil and Kurt have now teamed up with UCCE farm advisors
Ron Vargas and Steve
Wright and are working closely with industry personnel,
PCAs, and the irrigation district manager to help manage this problem.
Researcher grows sunflowers to protect peaches from pest
If IPM Advisor
Walt Bentley has his way, sunflowers will offer a ray of hope in
the battle against the oriental fruit moth.
The oriental fruit moth is one of the most important pests of peaches and nectarines in the
world. The female moth lays eggs on the fruit,
and the eggs hatch into larvae which immediately attack the center
of the fruit and feed around the pit, making the fruit unfit to
oriental fruit moth entered the United States on flowering cherries
imported from Japan in 1916. The pest quickly spread
United States but did not reach California until 1942, prior
to the development
and use of synthetic contact poisons such as DDT.
insecticides used prior to WWII were ineffective against this pest,
the USDA developed a program of mass production
of a parasitic
wasp that effectively manages the oriental fruit moth in those
states East of the Rocky Mountains. The wasp lays its eggs
inside the pest's
larval stage, and then the wasp larva develops within, killing
the pest. Once DDT became available, the parasite release program
was stopped in
The parasitic wasp does not survive without a host
through the winter on oriental fruit moth, and it had to be reared
annually for release in orchards. The decline of this biological
control program over the years was due to the easy use and
new insecticides, which also killed the wasp.
But, if Walt's research bears fruit, the parasite will be able
to live inside the sunflower moth caterpillars through the winter; reducing
or eliminating the need to use insecticides on late- harvested fruit. "We've
always had good management of the oriental fruit moth when fruit is harvested
before August when we're using mating disruption," says Walt. "Our
problems occur with fruit harvested after July. There we often have used
supplemental sprays. Macrocentrus may be able to eliminate the need for
these sprays that occur late in the season."
of the oriental fruit moth has contributed to the continued
use of broad- spectrum pesticides in stone fruit
in the San
Currently, pesticides are used along with mating disruption
to manage this pest. But infestation has continued to occur
after August, necessitating the use of late-season insecticides.
Since regulatory agencies have targeted these insecticides
to be phased out
because of surface-water contamination, an IPM approach is
With support from the UC Specialty Crops Grant Program, Walt
has planted sunflowers on a 1/3-acre patch at the Kearney
Research and Extension
Center in Parlier, California, next to a peach orchard infested
with oriental fruit moth. To date, his sunflower harvests
no damage from the pest.
Walt's research shows sunflower moths can help provide a higher
population of the beneficial parasite earlier in the season
while maintaining the oriental fruit moth at lower levels. Used in conjunction
disruption, parasites living in sunflowers planted near a
peach orchard could control late-season infestations, eliminating the
need for supplemental
Mating disruption makes use of the insect's own sexual scents,
or pheromones. Researchers tie little chips with the female
pheromone onto branches;
the pheromone confuses the males and disrupts the mating
process. The dispensers, which are acceptable for produce
as organically grown, are placed in trees at the first
an oriental fruit
moth in late February to early March. Current products
will last into
but fruit harvested later needs the additional help of
"Our experiments indicate that parasitism is greatest in late-harvested
orchards from late July on," says Walt. "We believe this
high level of parasitism will result in low survival for the oriental
fruit moth in subsequent years, making mating disruption even more effective.
We now plan to expand this biocontrol effort to late-harvested peaches
and nectarines, combined with mating disruption, to reduce late-season