The war between Washington state's apple growers and their primary pest, the codling moth, has raged for nearly a century. The larval moth's passion for burrowing into the flesh of the fruit has brought the apple industry to its knees more than once. Orchardists have fought back with a battery of deadly weapons, ranging from lead arsenate - which was held responsible for the deaths of horses that worked in the orchards early this century - to DDT, best known for driving the bald eagle to the brink of extinction.
Then, in 1991, scientists
unveiled a much more sophisticated weapon:
In an increasing number of Washington apple
orchards, growers are flooding their land with synthetic
pheromones. These impostors mimic the female moth's natural
pheromones, which act as a trail the males use to locate them. The
synthetic pheromones confuse the males. They can't find a mate and
die childless. The result: Codling moth larvae don't nibble into
the billion-dollar earnings of Washington's premier crop.
Pheromones have virtually no environmental impacts. By the turn of
the century, they could be used on half of the state's apple
orchards. This would reduce the use of Guthion by about 260,000
pounds per year; this potent neurotoxin has been the favored
pesticide used against the codling moth since the
Why is the apple industry pursuing this?
First, the codling moth is starting to build immunity to Guthion.
Second, the federal government is cutting down on the pool of
insecticides that farmers can use. "We're seeing the beginning of
the end of an era of the use of broad-spectrum insecticides," says
Jay Brunner, a Washington State University entomologist researching
pheromonal control of codling moths, as well as "soft program"
controls for other pests. "It's the only alternative we have. The
pesticides we're using will be gone to regulation or resistance."
Observers consider "soft-path" pest control a
perfect example of what land-grant researchers should be doing:
helping growers stay in business, and reducing the environmental
development of new pesticides is hampered by the time and money it
takes to develop and register them with the Environmental
Protection Agency. While pesticide companies invest in new
chemicals for "major" crops like wheat, "minor" crops like apples
may not be worth the effort. Although Washington's 3,500 apple
growers produce up to a billion dollars a year, apples only
generate about one-tenth of what wheat does nationwide. And 1988
amendments to the national pesticide law have mandated that all
pesticides currently in use be re-registered. That can cost
millions of dollars per pesticide with no guarantee the substance
will pass muster, either environmentally or in terms of its effects
on human health. Re-registration has taken a heavy toll. In 1988
there were 45,000 commercially available pesticides; now there are
There are other, less quantifiable
reasons for the fruit industry's eagerness to change. In February
1989, public concern skyrocketed over Alar, which preserved
firmness as well as enhancing the color of Red Delicious apples.
Alar's allegedly carcinogenic qualities made headlines and were
mulled over on talk shows. The state apple commission was flooded
with phone calls from panic-stricken consumers, asking such
questions as, "Is it safe to pour apple juice down the drain?"
The apple industry went ballistic.
"Hundreds of growers were coming from eastern
Washington to learn about organic growing," says Miles McEvoy, the
organic program manager for the Washington State Department of
Agriculture. "From their perspective, they were all going to have
to become organic growers." There were 11 organic apple growers in
Washington in 1988. By 1990 there were about
They flooded the organic market, and as a
result less than half of Washington's organically raised apples in
1990 were sold at the premium price commanded by organic fruit.
Growers flowed out of organic farming as fast as they had flowed
in, and it was not until last year that all of the organic apples
raised in Washington were sold as organic.
Alar scare left apple growers painfully aware of the mercurial
nature of public opinion. "The public thinks we're out here taking
advantage of workers, raping the land," says Rick Kamphaus, an
orchard manager near Chelan, Washington. "They said, "You guys are
bad guys." And by God, we're not bad guys."
growers are taking on the challenge of using "soft program" pest
control. Pheromones were used to control the codling moth on 1,500
acres of orchard in 1991. Now they are used on 20,000 acres - about
one-ninth of the state's total apple acreage. Ray Fuller, who uses
pheromones to control codling moths in his organic orchard outside
Chelan, says, "Mating disruption has made me a better
But pheromones don't appeal
only to organic farmers.
"I don't like spraying,
and I wish the people I had working with me didn't have to work
with spray," says Doyle Fleming, who grows 180 acres of non-organic
fruit and eight acres of organic on his Orondo orchard. "You just
keep on pushing, trying to gain as much knowledge as you can to
hopefully eliminate as much as possible."
many growers aren't ready to jump into an exclusively "soft-path"
regime because the new technologies aren't fine-tuned yet. For
instance, synthetic pheromones mimic the scent emitted by the
female codling moth to guide her mate to her. When there are
relatively few codling moths, the pheromones flood the orchard,
confuse the male moth, and disrupt mating. But when the orchard is
packed with the insects, the pheromone isn't as effective because
the moths can meet and mate randomly. Soft path controls are also
expensive: While prices are expected to drop when pheromone use
expands, it currently costs three times as much as
"Farming is a business," says Kamphaus.
He uses pheromone traps to monitor the codling moth population in
his orchard, but controls outbreaks with Guthion. This year's apple
crop is Washington's biggest in history, and growers fear prices
will be flat. "With the prices we're going to get for fruit this
year we're really going to have to cut costs. It sounds like
pheromones work real well, but the expense exceeds the expense of
Guthion." Kamphaus knows a lot about profit margins. He put 200
acres under an organic regime following the Alar scare. The orchard
lost $250,000 that year, an experience Kamphaus sums up as "the
Yet Kamphaus says he's on a soft path.
He applies Guthion at half the registered dose to preserve the
predator insects. Toward the same end he uses Dipel, a bacterial
insecticide, against leafroller. "It's organic and expensive, and I
use it to target one bug," he says. "I want to keep the good bugs
in the field. But if I could get a synthetic chemical that'd be as
specific and cheaper, I'd use it."
precisely the fact that soft path pest control leaves the predatory
bugs in the field that makes it a good economic bet for the farmer,
points out Andy Kahn, an entomologist and consultant based in
Wenatchee. Predators spared by "soft path" methods will kill pests
like aphids and leafminers, which destroy the leaves of the apple
trees, making them less productive.
"On one hand
we may be spending more to control codling moth and leafroller, but
we potentially will be spending less on controlling aphids and
leafminer," says Kahn.
Whatever the cost of the
materials, there is unanimous agreement on the fact that soft path
pest control is much more management-intensive than its traditional
counterpart. "If you put on a broad-spectrum insecticide you can
get into a little bit of trouble, but not a lot," says Larry Gut, a
post-doctoral entomologist at WSU. "If you use the pheromone and do
it just maybe slightly less effectively - if you don't put it on
right, if you don't monitor correctly, if you don't correct it -
you're in a lot of trouble."
The slack in
pest-management information is being filled in part by private
consultants, who are signing on with growers who are willing to do
the careful monitoring demanded by the soft pest
"There's a lot more going on on an acre
of land, and a lot more opportunity for things to screw up," says
Kahn, who has worked in the Wenatchee Valley for four years. "One
reason I've been welcomed here by people who might otherwise
consider me competition is that everything in the business has
gotten more complicated."
Indeed, the other
historical pest-management advisors - fieldmen from chemical
companies and fruit packing houses - are often busy with changes in
other areas of orchard management: Growers are planting "high
density" orchards, where closely planted trees barely larger than
saplings bear fruit. Irrigation and fertilization systems are
though some growers are hesitant about soft path pest control, the
fruit industry as a whole has accepted the need for it. The
Washington Tree Fruit Research Commission, which raises money from
growers for fruit research, will cover the losses suffered by
growers who participate in an on-farm soft path research project
next year. The project will compare conventional pest management
with a regimen that uses pheromones, bacteria and pathogens against
pests. At each of six sites, 10 acres will be treated with soft
pesticides. It will be funded by the federal government as well as
by the research commission.
The test growers
haven't been picked yet, but Jay Brunner, the project's principal
investigator, knows who he wants. "We're going after industry
leaders, good adapters, good spokespersons for the industry," he
says. "Down the road we'd like (growers) to be talking to their
Meanwhile, a group of researchers from
Washington State University and elsewhere is investigating whether
consumers are willing to pay more for "sustainably raised" produce
- a study which could go a long way toward making orchardists more
willing to try new, more costly technologies like pheromonal
control of codling moth.
doesn't mean organic. It means that wherever practical the grower
avoids chemical treatments, cuts down on water use and controls
"Mating disruption in apples costs
about $100 more per acre than conventional pesticides," says David
Granatstein, coordinator of Washington State's Center for
Sustaining Agriculture and Natural Resources, one of the
participants in the project. "So if we take that and translate it
into cents per pound, it's maybe two cents a pound more to produce
apples. That's not much. It shouldn't be a big deal. It's a heck of
a lot less than the 30 to 40 percent premium for organic food. Are
people willing to pay for that? Can they relate to that? Can the
retail system relate to that? ... In marketing you don't have the
luxury of explaining. It's black or white. So that's going to be a
real challenge; what's going to be the hook?"
The group - called the Marketing and Production
Alliance for Sustainable Agriculture - will start its four-year
study in this year with funding from the Kellogg Foundation. Its
participants come from industry and environmental groups in the
Northwest, as well as Oregon State University. The group wants to
avoid the certification approach, and instead use a
"process-oriented" approach that would assign points for different
practices, like water, soil practices and pesticide use, says
Granatstein. "We felt if we could get 50 percent of the growers to
go this way, we'd do a lot more environmental good than just have
.5 percent of them going organic."
For more information on
WSU's Center for Sustaining Agriculture and Natural Resources and
its programs, contact David Granatstein, Center for Sustaining
Agriculture and Natural Resources, WSU, 1100 Western Ave. N.,
Wenatchee, WA 98801 (509/ 663-8181, ext.