A significant number of farmers are not planting trees to help mitigate environmental effects of dairy farming, a new study has found.
The study by Lincoln University senior lecturer Wendy McWilliam found plantings were small, limited to unproductive areas, and many continued to be dominated by exotics and monocultures, even though natives and mixed species were preferred.
Dr McWilliam found government incentive programmes were not effective in overcoming barriers to planting, such as the higher cost and slow growth of native plants.
Another barrier was the perception of planting being of little direct benefit to farmers' operations, she said.
The study's results showed few farmers took advantage of government planting incentive programmes, largely because they did not cover enough of the costs.
It found many farmers were increasing woody vegetation - particularly around waterways and wetlands - to provide public ecosystem services, such as water cleansing and nature conservation.
However, many were also removing or replanting their shelterbelts and hedges.
The government and the dairy industry needed to work closely together to develop and maintain a landscape-scaled woody vegetation network on both private and public land, Dr McWilliam said.
Dairy farmers may also be motivated by stronger evidence in support of valued ecosystem services, including their benefits and drawbacks.