Waiapu Soils

The soils of Waiapu Valley were mapped in detail to determine their potential for cropping including crops suitable for food processing. This report briefly discusses the physical and chemical properties of the soils in terms of the taxonomic units while a summary of properties for each mapping unit is given in the appendix. Distribution of the soils is shown on the accompanying soil map at scale of 1:25 OOO. The soils are classified according to their limitations for pastoral, cropping, horticultural, forestry and urban uses, as well as their value for food production in terms of the Town and Country Planning Act 1977. These classifications show that for most uses the main limitations of the alluvial soils of Waiapu Valley are either imperfect drainage, or shallow or stony profiles with low plant-available moisture particularly in summer. Well drained alluvial soils are suitable for intensive cropping and horticulture including sweet corn, tomatoes and maize. Soils on the high terraces derived from volcanic ash are suitable for crops such as maize, sweet corn, carrots and wheat. Soils with drainage limitations can also be used for growing crops suitable for food processing, provided adequate artificial drainage is carried out.