California Bill Would Take Pest Control Decision Away from Scientists

Published May 1, 2008

With federal and state scientists supporting a plan to spray pheromones to eradicate the invasive light brown apple moth, some California legislators are supporting legislation to give the governor, instead of scientists, authority to decide when pesticide and pheromone spraying is a safe and desirable option for controlling insect pests.

Reminiscent of the public upheaval surrounding the Mediterranean fruit fly (medfly) infestation in the early 1980s, concern over the light brown apple moth is leading farmers to call for quick and complete eradication of the pest. But activist groups are resisting any use of pesticides.

The larvae of the light brown apple moth cocoon inside rolled leaves, blemishing ornamentals and reducing the vigor of a wide range of plants, including fruit trees and grapes.

U.S. Department of Agriculture (USDA) and California Department of Food and Agriculture scientists are convinced there must be quick aerial spraying to eliminate the moth. They say the pest arrived only recently and its larvae threaten more than 200 crops in the state, worth many millions of dollars per year. Nursery plants and native trees are also at risk.

Spraying Has Begun

USDA warns the light brown apple moth can substantially harm fruit trees, grapes, and ornamentals. USDA and the California Department of Food and Agriculture have already sprayed a pheromone known as CheckMate over Santa Cruz and Monterey counties. They plan to spray parts of San Francisco, San Mateo, Marin, Alameda, and Contra Costa counties this summer.

USDA is confident the pheromone, which is nontoxic but disrupts the mating impulses of light brown apple moths, is safe for humans and the environment. After spraying in Santa Cruz and Monterey counties, however, some residents reported shortness of breath and headaches. No scientific link has been established between these minor, self-reported symptoms and CheckMate.

Moth Threat Downplayed

In addition to a bill seeking to take the spraying decision out of the hands of scientists at the appropriate agencies, another Senate bill, SCR 87, asks the California Department of Food and Agriculture to impose a moratorium on spraying until it can more thoroughly demonstrate the pheromone compound is safe for humans and effective at eradicating the moth.

Some scientists siding with environmental groups say the insect may not be the voracious threat portrayed by state and federal agricultural officials.

The $74.5 million program for the aerial spraying and related activities should be used instead to contain the moth and “slow the spread as much as possible to the Central Valley, if it’s not already there,” said James Carey, University of California at Davis entomology professor, for a March 6 San Francisco Chronicle story.

“It’s virtually impossible to eradicate them,” said Carey, who spent seven years on the state Department of Food and Agriculture’s medfly scientific advisory panel. Carey estimates the light brown apple moth has been in California at least 30 years and perhaps 50 or more.

The state and federal agricultural departments need to acknowledge “the pest has been here so long and is so widespread” that they don’t have the tools or the monitoring technologies to achieve actual eradication, Carey said.

Pheromones No Threat

USDA disagrees. Spokesman Larry Hawkins told the Chronicle, “There has never been an opportunity like this one to use a product as benign as a pheromone to eradicate a pest.”

Fears of environmental harm are severely overstated, experts report. “Spraying is about as dangerous to humans as the cologne most people spritz on themselves before they go to work,” said Jonathan Tolman, an adjunct scholar at the Competitive Enterprise Institute.

“The assertion that moth pheromones pose a threat to the environment or human health has no basis in sound science,” said Tolman.

“When will it become obvious to the public that environmental alarmists take whatever position stands in the way of human progress?” asked Dr. Jay Lehr, science director for The Heartland Institute.

“They do not want us to use any pesticides to kill any pests, so we develop pheromones that interfere with mating and reproduction,” Lehr noted. “Then they send up a false smokescreen scaring people away from this effective and harmless technique.

“It is terribly easy to scare people, with no evidence whatsoever, and that is what the environmentalist alarmists have been doing quite effectively for decades now,” said Lehr. “The moth is destructive to society, and pheromones are safe and effective. Let’s get on with their use.”


Tom Tanton ([email protected]) is a senior fellow at the Pacific Research Institute.