If a farmer chooses to allow a visitor on to their farm, they have a duty to at least verbally warn them of work-related, out-of-the-ordinary hazards.
This covers any hazards arising from a work activity on the farm, which would not normally be expected and could cause a person serious harm. Examples include tree felling, earthworks or pest control operations. Farmers are not liable for warning visitors of natural hazards such as rivers, caves and wasp nests.
Farmers must let some people on to their property; authorised council staff, fire-fighters in emergencies and the police, who can search your property with a search warrant, for example.
Farmers have a duty to warn these people of "out of the ordinary" hazards, but only where they have been given oral notice of a visit.
Other visitors such as stock-truck, milk-tanker drivers or electricity transmission line workers have pre-existing arrangements.
Things change if a farmer chooses to charge people for using their land for activities such as camping or guided tours.
These visitors then become customers and there is a full duty to take "all practicable steps" to ensure they are not harmed by any hazard arising on the farm.
"All practicable steps" means things that can reasonably be done to ensure people are not harmed, such as restricting access to places with hazards or setting weight limits for bridges.
Federated Farmers members can call 0800 327 646 for specific legal advice regarding farm visitors or the Ministry of Business, Innovation and Employment's Labour Department may also be able to assist.
Kelly Langton is a Federated Farmers regional policy adviser