But ABC7 found one researcher who went to New Zealand to learn more about the apple moth and the danger it poses.
Daniel Harder is the director of the UC Santa Cruz Arboretum. It's home to the largest collection of New Zealand and Australian plants outside of those countries.
The light brown apple moth, or LBAM, is native to Australia and has lived in New Zealand for more than 100 years.
In January, Harder went on a three-week research mission to New Zealand to learn more about the /*apple moth*/ threat.
"From what we found out in New Zealand, it's not much of a pest and doesn't cause that much damage, at most one percent," said Harder.
Harder wrote up his findings in a 14-page report that concludes eradicating the pest is simply not possible and probably not necessary. He says the moth's natural predator's such as birds, spiders and earwigs are the best offense and proven to control it in New Zealand.
"In California there are over 300 species of tortricid moths, the same family as the light brown apple moth, and none of those populations in California ever get out of control because of those natural predators that are here," said Harder.
The state strongly disagrees and maintains LBAM in California constitutes an emergency. It wants to continue aerial spraying of a pheromone designed to confuse the male moth from mating.
A coalition of scientists advising the USDA on LBAM wrote a seven-page response to Harder's findings.
The technical working group said: "The reports account of the LBAM situation in New Zealand fails to recognize the natural resistance of New Zealand's native plants and the long history of scientific studies and bio-control program development that have just recently resulted in the reduction of this pest's impact on the country's agricultural sector."
Dan Harder is standing firm and has been on the winning side of two recent court cases in Monterey and Santa Cruz counties. Judges there ruled the light brown apple moth is not an imminent threat and ordered the state to conduct full environmental studies before continuing its spraying operations.