Research on the consequences of converting to organic production : a review of international literature and outline of a research design for New Zealand

The objectives of this research were to review the literature that describes the consequences of farms converting to organic production and to use these studies to develop an optimum design for an organic farm conversion study in New Zealand. Research to date has been either longitudinal research on organic farms only or static/comparative with direct comparison between organic and conventional farms. The Before-After-Control-Intervention (BACI) design advocated here builds on both types of research by reporting changes over time as some farms undergo conversion while others maintain conventional production. Research using this design is needed in New Zealand because we cannot assume that results from the international literature necessarily apply in New Zealand. The absence of significant New Zealand research needs to be redressed with careful and thorough study of farm conversion focusing on the full range of relevant variables including: environmental, economic, social, extension and health factors