Federated Farmers is calling for action on stewardship land following backing from the Parliamentary Commissioner for the Environment.
Stewardship land was Crown land put under the care of the Department of Conservation (DoC) when it was set up in 1987.
The future of the land - whether it was to be farm land or conservation land - was to be decided at a later date.
But almost 30 years later Federated Farmers board member Katie Milne said nothing had happened.
Ms Milne said farmers might want to swap land they own which has high conservation value, with adjoining blocks of land managed by DoC which would be better suited for farming.
"Because there are blocks that farmers do have, whether they're bush blocks or wetland blocks, that sometimes do already adjoin DoC, which could be better off in the estate and there may be a piece of DoC somewhere else - either adjoining their land or not, which is not of high conservation value - that may be well placed to go back to do a land swap with that farmer.
"If there's better conservation outcomes ... then that would be a good outcome all round."
Parliamentary Commissioner for the Environment Jan Wright agreed with Federated Farmers that the issue needed to be sorted out.
She said DoC had identified a number of land areas for review, and needed to pick up the pace.