The Light Brown Apple Moth

March 14, 2008

Light Brown Apple Moth An agricultural pest smaller than the nail on your pinky finger is stirring up big controversy in the Bay Area. The caterpillars and larvae of the light brown apple moth (LBAM), native to Australia, feed on more than 250 different types of agricultural crops and native plants. When in 2006 the pest was discovered for the first time in California, agricultural officials were sent into a frenzy of planning for its eradication. The centerpiece of the California Department of Food and Agriculture’s plan to exterminate the moth—aerial spraying of a product called CheckMate LBAM-F—is being passionately opposed by many urban and rural residents.

There is no question that the threat of agricultural pests must be taken very seriously in a state with a 32 billion dollar agriculture industry. The presence of the LBAM has already led to import restrictions by countries that want to keep the moth out, and the pest could impose serious crop damage if populations grew. But right now, the LBAM eradication strategy is wreaking more havoc than the pest itself. In September of 2007, the CDFA began the aerial application CheckMate to Monterey and Santa Cruz counties. Recently, they announced plans to spray several Bay Area counties beginning in August.

CheckMate is a synthetic pheromone: it works to confuse male moths by simulating the pheromone that female moths release when they are ready to mate. CheckMate does not kill moths, but renders them unable to locate each other for mating. Failed reproductive cycles eventually lead to dwindling populations. Many ecological farmers are familiar with the use of pheromone disruption—it’s a non-invasive way to deal with pests that is used frequently in organic orchards, where the chemical is sprayed from the ground or released from ornaments that hang from trees. Using pheromones is far preferable to using synthetic poisons that can kill much more than just the pest they are targeting. But these synthetic pheromones are rarely applied aerially, and some worry that the aerial application of an otherwise fairly benign chemical could damage ecology and human health.

Besides the synthetic pheromone, CheckMate contains inert ingredients. These “inerts” are the primary concern of those opposing the spray. According to the US Environmental Protection Agency, “An inert ingredient means any substance other than an active ingredient, which is intentionally included in a pesticide product. Inert ingredients play a key role in the effectiveness of a pesticidal product. For example, inert ingredients may serve as a solvent, allowing the pesticide’s active ingredient to penetrate a plant’s outer surface. Pesticide products can contain more than one inert ingredient, but federal law does not require that these ingredients be identified by name or percentage on the label.” The list of inert ingredients in CheckMate was released, and some experts are concerned about potential negative health impacts, though no studies have been done on the long-term effects of their use in an aerial spray.

The Pesticide Action Network of North America (PAN) “is calling for an open, transparent and comprehensive review of all least toxic alternatives and for expedited research, development and implementation of less invasive approaches such as biological control and integrated pest management (IPM) that exclude use of organophosphate pesticides. PAN supports the use of pheromones (in, for example, ground applications) and other ecologically sound organic IPM approaches as far preferable to and ultimately more effective than use of dangerous organophosphates such as chlorpyrifos. However, PAN does not endorse further aerial applications of CheckMate products due to questions regarding inert ingredients in these products (their actual concentrations and possible adverse health impacts)… We call for precautionary steps by CDFA and analysis by an independent science panel before any further spraying.”

Similar sentiments are echoed by other ecological farming organizations, including California Certified Organic Farmers and Marin Organic.  

Light brown apple moths were discovered at Green Gulch farm last year, and Sara Tashker, the farm’s manager, is worried that if moths are still present in late spring, they won’t be able to cross the Golden Gate Bridge into San Francisco, where they make more than 75% of their income at the Ferry Plaza Farmers Market. Still, the San Francisco Zen Center, which operates the farm, opposes aerial spraying. In a statement to the Marin Agricultural Commission Tashker wrote, “As the operator of a certified organic farm and steward of private in-holdings within protected wilderness areas in both Marin and Monterey Counties, we at the San Francisco Zen Center recognize the importance of controlling invasive species. However, we believe that overall environmental and ecological health must be the basis for any proposed eradication strategy.” 

Joel Schirmer of Dirty Girl Produce thinks it’s unlikely that aerial spraying of CheckMate will actually eradicate the pest, and he worries that the biggest effect of the LBAM will be the loss of income that farmers face when they are quarantined. His farm his been inspected monthly for the moth since May of 2007.

Striking the right balance of protecting California’s agricultural economy and food security and protecting its people and ecology presents the state with a complex problem. You can learn more about this issue by checking out the following website and articles:

Experts question plan to spray to fight moths >

Pesticide maker owned by political donor  >

Migden battles aerial moth spraying >