Scott Espinoza and Sound Cannons (copy)

Scott Espinoza, who lives next to a vineyard on North Kelly Road, complained in 2017 that the owner of the vineyard uses propane sound cannons far more than is needed to scare off birds. Napa County on Tuesday set standards for propane cannon use.

Napa County has new rules to help south county residents who say constant “booms” from bird-scaring propane cannons in vineyards can be an annoying tattoo of noise.

The Board of Supervisors on Tuesday approved standards for propane cannon use, such as limiting how long and what times of the day cannons can be shot. That comes after several months of work that included community meetings and a Planning Commission session on the topic.

“It’s unfortunate we find ourselves in a situation where we have to regulate behavior to do the right thing,” Supervisor Belia Ramos said.

Supervisor Brad Wagenknecht said he’s shown the guidelines to farmers and concluded that 99 percent of them already use this type of good sense. The standards are for those who need a guide to good sense, he added.

Napa County Farm Bureau CEO Ryan Klobas said before the meeting that the group’s board of directors finds the new bird cannon standards as being acceptable. The group is willing to help work with any bad actors who don’t follow the standards, he said.

“A lot of our members thought these (standards) were things that are already commonplace,” Klobas said.

Birds eat grapes and damage fruit, leaving it more susceptible to pests and pathogens. A study in 2013 estimated the wine grape crop in California suffered $49 million in damage caused by birds, a county report said.

Napa County has received complaints over propane cannons that create bird-scaring noise from such places as western American Canyon. One city resident previously said that during the growing season he hears cannons shot every two seconds or so from the Carneros area several miles away.

Over three years, the county Agricultural Commissioner’s Office received 30 complaints about propane cannons. The Sheriff’s Office and Planning, Building and Environmental Services have also received complaints, a county report said.

The county’s right-to-farm ordinance protects agricultural activities done according to accepted customs and standards. But the county hadn’t previously adopted customs and standards for propane cannons.

That made it difficult for county code enforcement to rein in cannon users who went beyond what Wagenknecht called “good sense.” The right-to-farm ordinance helped shield them from nuisance charges.

“Right-to-farm is very important in Napa County,” Wagenknecht said. “(But) right-to-farm is not a blunt instrument to be used on your neighbors.”

What has been a controversial issue didn’t appear controversial on Tuesday. South county residents who had previously complained of propane cannon noise didn’t address the Board of Supervisors.

Scott Espinoza and Jennifer Leslie are among those residents. They raise goats and chickens along North Kelly Road and have accused a neighbor with a vineyard of using propane cannons to harass them.

“I think the standards they came up with are a lot better than they told us they’d do early on,” Espinoza said by phone on Tuesday.

Leslie said they have been faced with four to five cannons directed at their house going off for 14 hours to 16 hours a day during the growing season. She’s worn gun-range protection hearing to go into her yard.

“There are a lot of good wineries and vineyards that are trying to do the right thing,” Leslie said. “And I think there are a few bad actors who are using the right-to-farm to weaponize and harass their neighbors.”

The new standards are for propane cannons and other audible frightening devices.

Among other things, the new standards say users must monitor and document crop damage to establish the need for the devices. They can place no more than one device on every five acres of agricultural land and use the devices only when fruit and berries begin to change color.

Users must position devices at least 600 feet from any house or occupied animal enclosure except their own, with the cannon barrel or speaker box pointed away.

They can use devices in the morning starting no earlier than 30 minutes before sunrise and for no more than three hours. They can use them in evenings for three hours and no later than 30 minutes after sunset.

“A lot of the complaints we were getting is the devices were on all day disturbing people at all times of day,” Agricultural Commissioner Humberto Izquierdo said.

If the devices are left on all day or left in the same places every day, the birds become habituated to the noise and the cannons aren’t useful, he said.

Subscribe to Daily Headlines

* I understand and agree that registration on or use of this site constitutes agreement to its user agreement and privacy policy.

Napa County Reporter

Barry Eberling covers Napa County government, transportation, the environment and general assignments. He has worked for the Napa Valley Register since fall 2014 and previously worked 27 years for the Daily Republic of Fairfield.