FRESNO, Calif. (CN) — In a corner of California’s $47 billion agricultural industry, millions of tiny workers put in long hours for no pay: wasps that feed on citrus pests. Now a company that raises them has sued a farm corporation for selling it pesticide-laden squash that it blames for killing its wasps.
Mulholland Citrus rears micro wasps (Aphyitis melinus) to control California red scale, a pest native to South China that was introduced in California in the 19th century.
The female scale, no more than 2 millimeters in diameter, has a hard, reddish-brown cover on top and is white underneath. The yellow males are even smaller, and live for only 6 hours, for the sole purpose of mating.
Females produce 100 to 150 nymphs at a time, which settle on plants’ twigs, leaves and fruits and feed by sucking sap from plant tissues. The saliva they produce is highly toxic and may disrupt shoot and leaf growth, cause discolored, pitted, unmarketable fruit, and kill the host by causing branches and twigs to die.
Controlling the pest is difficult, as their hard covers protect them from most pesticides. They are becoming resistant to many chemicals, and heavy use of insecticides has decimated populations of their natural predators.
Mulholland’s micro wasps are one of the scale’s natural enemies. The Fresno County-based company rears its wasps on oleander scale, an insect similar to red scale, which itself feeds on banana squash.
“Once the oleander scale on the banana squash matures, the wasps are introduced and lay their larva in the mature oleander scale on the banana squash. The oleander scale is very sensitive to pesticides, especially the systemic neonicotinoid pesticide known as ‘Imidacloprid,” Mulholland says in its lawsuit against Vantaggio Farming Corp.
Mulholland Citrus seeks $455,000, and punitive damages, in its Jan. 5 complaint in Fresno County Court.
It claims that in December 2015 it bought 124 bins of banana squash from Vantaggio, under the condition that the squash be pesticide-free, to rear wasps. When the shipment arrived in late May 2016 Mulholland put the oleander scale on the squash to grow.
Within 25 days, all of its oleander scale died, leaving it without the host for its wasps, the company says, and lab tests came back positive for Imidacloprid.
Without its wasps, Mulholland could not fulfill many of its contracts to citrus growers, losing sales, customers, and suffering harm to its business reputation, the company says.
Mulholland claims that Vantaggio “never intended to provide the banana squash pesticide-free, as defendants promised,” but made the “promise without any intention of performance … with the intent to defraud and induce plaintiff to purchase the banana squash.”
Vantaggio did not respond to emailed requests for comment Tuesday.
Mulholland seeks $454,549.32 in consequential damages, and damages, for breach of contract, breach of express and implied warranty, negligence, negligent interference with economic relationships, and promise without intent to perform.
It is represented by Jan Kahn with Kahn, Soares & Conway, in Hanford, who did not return emailed requests for comment.