Jack Kelly Clark

Light brown apple moth

As California struggles with how to address the recent arrival of the light brown apple moth, New Zealand's experience with this invasive crop pest may be instructive.

A review article in the January-March 2010 issue of the University of California's California Agriculture journal details how crop losses in New Zealand were reduced to virtually negligible levels following the adoption of an integrated pest management (IPM) program, which included reduced-risk insecticides and introduction of parasitoid insects that attack light brown apple moth (called "biological control").

The peer-reviewed article, by UC Integrated Pest Management advisor Lucia Varela and scientists with the New Zealand Institute for Plant & Food Research, can be viewed online at http://californiaagriculture.ucanr.org.

In 1986, light brown apple moth damage to unsprayed apple trees in Hawke's Bay, New Zealand, peaked at over 40 percent. In 1996, a pilot Integrated Fruit Production Program was introduced, replacing decades-long reliance on frequent sprays of broad-spectrum insecticides. At the same time, parasitoid insects were expanding their ranges and new species were introduced. Since 1998, crop damage has been between 4 percent and nonmeasurable levels in Hawke's Bay apples.

"With a strategic commitment to biological control within an IPM context, California may ultimately achieve the same levels of light brown apple moth control as obtained in New Zealand," Varela and colleagues write in California Agriculture journal.

New Zealand consists of two large islands in the Southern Hemisphere, which extend the length of California, Oregon and Washington state, at approximately the same latitudes. New Zealand's climate is similar to that of coastal California and acreages of crops that host the light brown apple moth, such as pome and berry fruit, are similar to those of California.

California Agriculture is the University of California’s peer-reviewed journal of research in agricultural, human and natural resources. For a free subscription, visit http://californiaagriculture.ucanr.org, e-mail calag@ucop.edu or call (510) 642-2431 x33.

EDITORS:  To request a hard copy of the journal, e-mail jlbyron@ucdavis.edu.