A vineyard worker in the Sonoma Valley died May 1 when he was crushed by a piece of mowing equipment that he was trying to untangle from vineyard wire, a local newspaper is reporting.

The accident occurred at about 7:30 a.m. in a vineyard managed by the Napa, Calif.-based Walsh Vineyards Management, the Santa Rosa Press-Democrat reports. The tilling tines of the worker's tractor got tangled in a vineyard wire, and it appeared that as the worker tried to free the wire, the tiller attachment dropped and crushed him, the Sonoma County Sheriff's Office told the newspaper.

The state Department of Industrial Relations' Division of Occupational Safety and Health is investigating the accident.

Walsh Vineyards Management provides a full range of services for vineyards in the Napa and Sonoma valleys, including vineyard development, ongoing farming, viticulture expertise, harvesting and delivery, according to its website.