State Watch

California neighborhood under quarantine due to invasive fly species

Santa Clarita Valley (Getty Images)

(KTLA) — An invasive fly species has prompted the quarantine of an upscale Southern California neighborhood, the first of its kind in the Western Hemisphere.

The Tau fruit fly is native to Asia and is a “serious pest for agriculture and natural resources,” according to the California Department of Food and Agriculture.

The flies can be typically found on a variety of fruits and vegetables along with a “select range of native plants in California,” officials said.

After the detection of more than 20 Tau flies in the Stevenson Ranch area of the Santa Clarita Valley, a quarantine was placed on residents.

The quarantine area spans about 79 square miles, bordered on the north by Castaic Junction, on the south by Oat Mountain, on the west by Del Valle, and on the east by Honby Avenue.


Stevenson Ranch is an upscale neighborhood with a median home price of $1.15 million dollars according to Redfin.

The invasive Tau fruit fly has prompted the Stevenson Ranch community to be placed under quarantine, the first of its kind in the Western Hemisphere. (California Department of Food and Agriculture)

Officials believe the fly was introduced to Los Angeles County by travelers who brought uninspected produce into the state. Agriculture officials note this is a common way for invasive species to arrive.

To prevent the species’ further spread, quarantined residents are asked not to move any fruits or vegetables away from their property. The produce they own may be safely consumed or processed, but must remain at the property.

If residents choose not to consume their produce, they must be disposed of by “double-bagging in plastic and placing the bags in a bin specifically for garbage,” officials said.

CDFA is working with the U.S. Department of Agriculture and the L.A. County Agricultural Commissioner to “utilize a multi-tiered approach to eliminate the Tau fruit fly and prevent its spread to new areas.”

On properties within 200 meters of fly detections, crews will cut host fruit and vegetables to inspect for present fly larvae. Those properties will also be treated with a “naturally derived organic-approved material known as Spinosad, which will help remove any live adult fruit flies and reduce the density of the population,” said CDFA.

Fly traps that incorporate a pheromone along with a small amount of pesticide will also be placed throughout the treatment zones.