By MARYLEE SHRIDER , Californian staff writer
e-mail: mshrider@bakersfield.com
Posted: Sunday February 29th, 2004, 10:05 PM
Local almond growers have cut their use of some highly toxic pesticides by 57
percent over the past five years, according to a new report by the Department of
Pesticide Regulations.
Growers have markedly reduced their use of
organophosphates and carbamates, older classes of toxic pesticides that tend to
remain in the environment longer than some newer, more environmentally friendly
compounds.
Concern over the environmental impact of these
pesticides has been an issue since the 1980s, when researchers found levels of
them in surface waters of the Sacramento and San Joaquin River basins. These
particular pesticides were commonly used in the winter season to control major
almond pests like mites, navel orange worms and peach twig borers.
Department Director Paul Helliker said rain runoff
during the winter months carried the pesticides into rivers and streams.
Although pesticide levels posed little threat to human health, they were high
enough to harm aquatic organisms and threaten the health of downstream
ecosystems.
The department "had a legal obligation to take action," Helliker said in an e-mail. "Almond growers also recognized the problem."
The older pesticide reduction, Helliker said, is a
direct result of efforts by the Almond Pest Management Alliance, a research team
of almond growers, UC researchers and pest control advisers. The alliance,
funded by the state and the Almond Board of California, was formed in 1998 to
find environmentally friendly alternatives to organophosphates.
"Rather than immediately proceed to regulatory
restrictions that could have disrupted the industry, we wanted to work together
through the Pest Management Alliance," Helliker said. "The results have been
gratifying."
Whereas the number of older pesticide applications
has plummeted, Kern almond growers' total use of substances -- toxic or
otherwise -- to combat pests has remained steady. David Moore, deputy
agricultural commissioner, said those numbers are good news, not bad.
"It means growers are moving from organophosphates
to softer, less toxic pesticides," he said. "The newer sciences don't have the
environmental concerns the others did."
Few would dispute that the reduction of
organophosphates is a good thing, but some environmental researchers like
Charles Kratzer, a hydrologist with U.S. Geological Survey, question the safety
of the newer pesticides.
"It's good news that there's been a big reduction
throughout the state on the OPs (organophosphates)," Kratzer said. "The question
still out there is, what has replaced it?"
Some growers, Kratzer said, have been applying pyrethroides, another class of
toxic pesticide that researchers have just begun to study. Pyrethroides, he
said, are difficult to test because of their highly undissolvable properties.
"They stick to the soil, to everything, including
the sample bottles, so they're hard to analyze," Kratzer said. "The growers have
taken care of a known evil, but replaced it with an unknown that could be a
bigger evil."
Department of Pesticide officials say pyrethroid applications in Kern County have gone up -- from 2,546 pounds in 2000, to 3,250 pounds in 2001 -- but alternative methods adopted by most local almond farmers are nontoxic oils or no treatments at all.
Dormant-season use of oil, a low-toxic application
that basically smothers the pest, has gone up from 1.48 million pounds in 2000,
to 1.58 million pounds in 2001 -- an increase of about 100,000 pounds in one
year, according to the report.
"Pyrethroides are highly toxic and under certain situations growers must use them," department spokesman Glenn Brank said. "But overall, we see an encouraging trend toward lower-toxicity applications."
No one is happier about the report than Mario
Viveros, the UC Cooperative Extension farm adviser who first petitioned to have
Kern County included in the project.
Kern, Butte and Stanislaus counties were chosen as field sites for the alliance project. Kern County, which produces 18 percent to 20 percent of the state's total almond crop on 94,000 acres, was an obvious choice.
"We grow a lot of almonds in this county, so we
wanted to see how well this program would work under our climatic conditions,"
Viveros said. "And we had a very willing grower to help us."
That grower is Thomas Vetsch, owner of Vetsch Farms
in Wasco. A soft-spoken, but passionate supporter of the alliance's
pest-managementtechniques,Vetschvolunteered160 of his 600 acres as a test plot.
So impressed was Vetsch with the results of the trials, he altered his farming
practices to include his entire acreage.
"We want to find the bridge from commercial to
organic production," said Vetsch, 45. "Not for the sake of being organic, but
for the sake of air, water and all living species."
The trial plot was divided into 16 10-acre plots.
Half the plots were farmed using conventional methods, including the use of
organophosphates, while the other half was farmed using integrated
pest-management techniques -- an approach to managing pests that combines
biological, cultural, physical and chemical tools in a way that minimizes
economic, health and environmental risks.
Cultural techniques include early harvests and
wintertime sanitation -- hand-picking any mummified or left-over nuts where the
navel orange worm might live for the winter.
Researchers also released beneficial insects that preyed on pests and experimented with synthetic and vegetable oils that essentially smother pests. The most effective technique to emerge from the trial, Viveros said, was orchard monitoring.
Growers, he said, will create less pollution and
save money on costly pesticides if they abandon the "scorched earth" method of
pesticide application, monitoring their orchards and spraying small sections
only when necessary.
"A lot of growers used to spray by the calendar,"
he said. "If it was time of year for a certain pest, they'd spray everything.
Now we know they should spray only when there's a need."
Vetsch said his pesticide costs dropped sharply
once he started monitoring and spot-spraying his orchards. His cost for weed
control in 2003 was $56 per acre, he said. Fungicide applications cost about $80
per acre, while insecticide costs were the highest at $90 per acre.
"Pesticides are our smallest production expense," Vetsch said. "Some growers probably spend as much as $400 per acre."
Vetsch could have lost a considerable portion of
his crop had the trials failed, but his participation paid off. Even with reject
levels slightly higher than growers who farm using conventional methods, Vetsch
has cashed in on California's record-breaking yields in recent years.
"Our reject level was only 1.62 percent last year," he said. "Higher than some conventional farmers, maybe, but still acceptable."
State funding for the alliance fell victim to
budget cuts, but the program is still
supported by the Almond Board -- for now. Local ag officials will continue
research and educational programs as long as possible, said Viveros, whose
regional field days at the sites have attracted more than 1,000 growers.
Vetsch, who was a pork producer in his native Switzerland, fell in love with almonds when he arrived in the United States 17 years ago. He learned the art of almond production as he went along, but swears he will never again use conventional pest-control methods. The first time he hired a crop duster to spray his orchards, he said, was the last.
"I walked through the orchard afterwards and found two dead birds," he said, shaking his head. "Never again."
http://www.bakersfield.com/local/story/4543725p-4590090c.html