All orchards in the Bay of Plenty will soon be listed on a Hazardous Activity and Industries register because of their regular use of pesticides.
The Bay of Plenty Regional Council, which is creating the list, says the register will help to identify potentially contaminated land if owners want to develop it in the future.
The council's project implementation officer, Emma Joss, said a build up of pesticide spray on land can affect human health and it was important the council kept a record of the land's use.
Ms Joss said a number of orchards had recently been found to be contaminated and not suitable for development.
But she said that would not be the case for everyone.
"This doesn't mean the land is contaminated, just that it might be. Overall this won't affect land owners unless they plan to repurpose the land in the future, such as by subdividing and changing to a more sensitive land use.
"Orchards are being targeted because of their use of persistent pesticides, so a lot of the historical uses of the site they used a lot of arsenic based sprays: there was lead, there's also a lot of issues with copper at the moment as well.
The council was having a lot of issues with existing orchards being subdivided in the Western Bay of Plenty, she said.
"Part of that is a requirement to have an assessment undertaken and a lot of that is coming back as not suitable for the land use."