The state of California has developed an extensive wine industry valued at several billion dollars. Unfortunately for the owners of the vineyards, the industry has had its share of troubles, mainly because of the European grapevine moth that forced officials to impose quarantines and forced vintners to undertake elaborate measure to protect their crops.
After a seven-year costly battle, the federal and state agricultural officials have said that the grapevine has been eradicated from California and its quarantine restrictions have been lifted. The eradication of this particular species of moth was the result of years of treatment and programs. The federal government assisted with the protection of California’s wine industry by providing $65 million in funding. Despite the best efforts of the local community invested in the wine industry and the federal government, the moth still managed to inflict damage worth several million dollars.
When the population of the grapevine moth was at its peak, it caused notable damage to grape crops across a large swath of the North Coast. Officials imposed quarantines on areas from Fresno County to Nevada County. The first year the insect was detected in the region, in 2009, it managed to destroy a vineyard’s Chardonnay crop in Oakville. Napa and Sonoma counties even had 446 square miles under quarantine since 2010. The growers were required to take additional precautions even when they started the harvest such as placing tarps over bins of freshly picked grapes, and wash all the equipment that was in a quarantined area.
The grapevine moth causes damage because its larvae feed on grape bud clusters and flowers during its bloom. This can lead to fungal infections that can easily spread through an entire vineyard. The infestation reached its peak in 2010 when more than 100, 000 insects were detected. This forced agricultural agencies and the wine industry to start a coordinated effort to cull their population through trapping and the use of insecticide.
The measure that officials say contributed to the eradication of the moth was the manufacturing of a pheromone that confused male moths when they tried to find females to mate with. The pheromone proved it’s efficiency quite fast, with detections dropping to 144 in 2011. The last moth to be detected in California was in Cazadero in 2014.
After this crisis, California’s wine industry is plague by an outbreak of Pierce’s disease that is forcing growers to pull out and replant thousands of vines. Researchers are trying to breed vines that are immune to this disease.
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