It happened at Killatree Farm this lunchtime (Wednesday)
A spokesman for Devon and Cornwall Police said: "Police were contacted by the fire service at around 1.10pm following an incident at Killatree Farm, in the Holsworthy area of Devon.
"It is reported that a man was in cardiac arrest at the scene.
"Despite the best efforts of those in attendance a man in his 80s was declared deceased at the scene.
"Next of kin have been informed of this incident, police are not currently treating this death as suspicious and a file is to be prepared for the coroner."