Why do we not terrace more hill slopes for agricultural production in Aotearoa/New Zealand?

New Zealand society has set agriculture the goal of reducing its environmental impact. In addition, the New Zealand Government is urging diversification within catchments and increased resilience for farms and rural communities. A technique from the past, still used in some parts of the world, could be of assistance – terracing. The practice of terracing hill slopes for agricultural production probably had two separate regional origins – dryland terracing in the Near East, and wet field terracing in south-east Asia. Dryland terracing began five to ten thousand years ago and the technology migrated west into Europe, south into North Africa, and east into the southern Pacific (Spencer & Hale 1961) where it was widely practiced throughout Polynesia (Leach 1984). Ten terrace forms have been recognised but the key functions common to virtually all of them were maximising productive use of available water and retention of silt. The modern practice of contour ploughing on moderately sloping land effectively forms mini terraces with the same functionality. The contemporary agricultural landscape of New Zealand hill country is distinctive for the almost complete absence of man-made terraces.