Mating disruption pays off

Capital Press

HOOD RIVER, Ore. -- It's not as if pear grower Erick von Lubken went kicking and screaming into using mating disruption for codling moth control.

But, he said, he had his doubts five years ago when he started the innovative pest-management program.

"I wasn't a true believer off the get-go," he said. "But once I saw what the benefits were, I became one.

"I'm a believer now," he said. "I've drank the Kool-Aid."

Von Lubken is one of 24 growers who have employed mating disruption in their pear orchards the past several years as part of two Hood River County integrated codling-moth control programs.

Participants tapped state and federal funds to help transition from organophosphate-based pest management to pheromone-based programs. The funds were primarily used to help purchase and apply the mating disruption dispensers. But growers today say they'll continue with the program with or without government support.

"(Government support) is not a necessary incentive anymore," said Steve Hunt, another orchardist involved in the program. "The cost-benefit analysis has come in, and we see that it pays off."

Federal funds obtained through an Environmental Protection Agency grant were also used to help reduce codling moth populations outside the targeted orchards, including in residential areas near orchards.

"You need to deal with what is going on outside the orchard," said Steve Castagnoli, a Hood River County extension horticulturist who helps coordinate the program. "And you need to have low pressure in the orchard for the program to work."

Castagnoli and a group of a dozen orchardists started the first program in the Dee Flat area in 2007. He and a similar number of growers initiated a second program in Odell in 2009.

An incentive of the programs is to find alternatives to broad spectrum insecticides commonly used in pest-control programs. The insecticides, growers said, were systematically killing beneficial insects that prey on the harmful insects. And some of the products, such as certain organophosphate sprays, are being phased out by the EPA.

For the first year or two, growers doubled up treatments, coupling mating disruption with their regular treatment programs to bring down codling moth populations.

"For a year or two, until you get the population down, you are spending a bit more money," Hunt said. "But after a few years, when you get codling moth controlled, you are saving money."

Trap counts of codling moth plummeted in the third year.

"Through a combination of implementing areawide mating disruption and well-timed supplemental sprays, they reduced their codling moth population from an average of 20 moths per trap in 2007 to one moth per trap in 2009," Castagnoli said.

In addition to reduced codling moth numbers, the program has dramatically improved biological control of secondary pests, such as pear psylla and mites, growers said.

"It is working very well," von Lubken said. "Codling moth now is pretty much nonexistent, and psylla and mites are extremely manageable."

Von Lubken said he has reduced his insect control costs from around $900 a year to $600 under the mating disruption program.

"We've knocked out probably two to three sprays during the summer," he said. "It has more than paid for itself."

"We are spraying less," Hunt said. "We are saving money. We are using less harmful chemicals. There are less worker concerns.

"It is a great tool," he said.

Looking back, Castagnoli said what the growers are doing in Hood River County "isn't anything brand new."

"But I don't know if anybody had done it with pears, and nobody had done it here," he said.