A small plane whizzes by, hovering low to the ground. One might think that the pilot is trying to have some fun, but in reality the airplane is ejecting certain chemicals to try to eliminate a pest.
This pest is the light brown apple moth, epiphyas postvittana, a non-native insect to North America. According to the California Department of Food and Agriculture. It is an invasive pest of California’s environment, natural habitat and agriculture. Because the Department of Food and Agriculture is fearful that the moth is capable of devastating California’s agriculture, an aerial spraying program has been set up to eradicate the moth.
The moth is a leaf roller and as an adult is about half an inch long. It is called a leaf roller because it rolls on the leaf using its silken thread to create a sort of tent-like home for itself. True to its name, the light brown apple moth has a shiny light brown coating and is said to cause damage to citrus, grapes and apples.
Since the moth is an exotic pest, it is difficult to know exactly how they were spread to North America.
“They are native to Australia and have been introduced into New Zealand, New Caledonia, Hawaii and Great Britain,” said Frank Zalom, professor of entomology at UC Davis. “Monterey and the San Francisco Bay Area are where LBAM were first recorded in North America.”
While it is not known exactly how the moth was introduced, the state speculates that they have been spread around by materials from plant nurseries.
The moth was put on a list of invasive species. It is listed as a Class A invasive species, meaning it is a species that is especially unwanted. Any place where the species is found, mile-and-a-half area surrounding the moth’s location is quarantined.
“Some of the speculation is that the leaf roller was in the nurseries before there was a quarantine and the nurseries could have planted them in other parts of the bay area” said Zalom.
Since the pest is exotic, there is a huge fear that there are no predators to keep its growth in check and that the moth’s feeding habits threaten agricultural plant species in California.
“Here, the biggest concern in my mind is the concern with not being able to ship plant material outside of quarantined area to other countries or states,” said Zalom. “In terms of the direct damage to the plants we have other native leaf rollers that do similar sorts of damage and basically our growers know how to control them.”
According to a human rights report released by Tom Kerns, a representative from the Environment and Human Rights Advisory, the California Department of Food and Agriculture has stated that unchecked, the moth spread could have an estimated economic impact of $160 to 640 million.
The department plans to eliminate the moth through aerial spraying. The spray releases a moth pheromone called Checkmate LBAM-F. Pheromones are chemical substances that are released by an insect which cause other individuals of the same species to react. In the case of moths, the pheromone usually helps to attract mates.
When the spray is released into the air, the male apple moth is supposed to think that a female is near, but the male becomes confused when he cannot locate the female. This keeps the species from breeding and thriving. The program also incorporates moth traps and plant treatments in order to more efficiently eradicate the moth.
The spraying will take place along the central coast and San Francisco Bay Area.
According to Kerns’ report, the California Department of Food and Agriculture initiated aerial spraying in September 2007 with an application over Monterey County followed by a second aerial application in November 2007 over urban areas of Monterey and Santa Cruz counties.
The department also plans to spray over Monterey, Santa Cruz, San Francisco, San Mateo, Alameda, Contra Costa and Marin counties. The aerial spraying is set to take place June 1, 2008 and is spaced 30 to 90 days apart.
Kerns’ report also lists the multiple human rights that the spraying violates such as the right to life, liberty and security of person and the right of the child to the highest standard of health.
Some people question the effectiveness of this eradication program.
“The invasion is so far advanced that it’s virtually impossible to eradicate,” said James Carey, an entomologist at UC Davis, during a KGO radio interview Apr. 1. “You need a tool that is effective in eradication, and this is not an effective tool.”
Many people in the communities that are being affected have become outraged with the sprayings. Several hundred people have reported adverse health effects from the first two sprays.
“The state says that it’s just a pheromone, but a pheromone is by definition made by an insect. This is a synthetic pheromone. The CDFA never released the concentrations of the pheromone in the spray. One can take the analogy where one aspirin can help take care of a headache, but 100 aspirins can kill you,” said Glen Chase, a resident of the central coast and supporter of the California Alliance to Stop the Spray.
In addition to the pheromone, the spray releases inert chemicals as well as a microcapsule. There has been concern that, within the microcapsules, there are carcinogens that could cause breast cancer in particular. The microcapsule is what keeps the pheromone suspended in the air, releasing it for a period of 30 to 90 days. The microcapsule, which ranges in size and may be as small as 10 microns, could potentially be inhaled and go directly into the lungs of residents in the spraying area.
“Four hundred fifty square miles will be sprayed, and there will be nowhere to hide. This is an experiment on humans. The only financial hardships come from the quarantines that the CDFA impose,” Chase said.
So far, no aerial spraying for the moth is set to take place in Davis.
“There has been no claim yet that the moth has been found in Davis or Sacramento,” said Chase.
For more information on the state’s plan to eradicate the light brown apple moth, visit cdfa.ca.gov. To access information on how to prevent the spraying, go to LBAMspray.com or cassonline.org.
YASSMIN ATEFI can be reached at science@californiaaggie.com. XXX
