SANTA CRUZ — The latest illegal pot farm bust took down more than 9,700 cannabis plants in 11 nonpermitted greenhouses managed by four full-time workers at Summit Road near Russell Ridge, a county spokesman said.

It is considered one of the largest sting operations against illegal commercial grow-ops in recent county history, spokesman Jason Hoppin said.

Santa Cruz County sheriff’s deputies had a search warrant that stemmed from an investigation at the property last year, when authorities observed the greenhouses on a graded and stripped parcel, Hoppin said.

On May 30, officers searched the 3,000-square-foot greenhouses at site in operation at least two years ago, Hoppin said.

The site’s full-time staff lived in a small trailer that left unfiltered sewage and household fluids flowing onto the property.

The property owner, who was not identified, faces civil fines and the property was red-tagged by county regulatory staff, Hoppin said. There were no arrests.

A separate enforcement last week nabbed 762 cannabis plants from a remote spread north of Boulder Creek.

In early May, the same authorities busted two unregulated pot grow-ops and confiscated thousands of cannabis plants. One operation had diverted water from a Bear Creek tributary. Officers located more than 2,700 cannabis plants, illegal weapons and a hoard of precious metals.

That raid at an 80-acre tract at the 500 block of Whalebone Gulch Road in Boulder Creek found 1,673 cannabis plants in large greenhouses, 61 pounds of processed cannabis, 50 pounds of recently harvested cannabis plants, almost 7 pounds of processed cannabis concentrate and $53,300 in cash, Hoppin has said. About $67,000 in gold and silver had been kept at the site. Authorities found three loaded guns: an AK-47 assault rifle, another assault rifle and a pistol. A rifle and numerous loaded high-capacity ammunition magazines and tactical body armor were confiscated.

No one was arrested in that case.

Authorities nabbed 1,079 marijuana plants from eight parcels at the 17000 block of Bear Creek Road in Boulder Creek last month during an investigation of unregulated commercial cultivation, illegal grading and stream diversions, Hoppin has said.

In January, authorities closed an illegal marijuana grow-op with nearly 2,000 plants and 46 pounds of processed marijuana in a Lake Boulevard house in Lompico.