The National Farmers Union is warning country dwellers to review their insurance cover because of a surge in theft.
The mutual, which is the leading provider of farm insurance in the UK, warns rural theft is now costing £100 million a year.
Agri-bandits using four-wheel drive vehicles and trailers have found isolated farms an easy target for rustling or stealing machinery.
But the countryside crime wave also includes a worrying rise in burglaries.
"In the past ten years crime in the countryside has risen seven fold," said underwriting manager Sid Gibson.
"In many farmhouses and county homes, furniture has been handed down from generation to generation with the result that it is viewed as just an old table or cabinet rather than a valuable antique.
"Many country folk need to reassess their valuables."