SOIL PREPARATION

DETECTION OF ROOT IMPEDIMENTS

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3.1 Soil inspection and sampling The first and most essential step in soil preparation is to dig profile pits to a depth of at least 1.2 m. This allows one to evaluate the soil type and to take soil samples for analyses (Figure 3.1). Inspection of a profile pit is necessary to identify the different soil horizons (layers), what soil type it is, what the main root restrictions will be, and to give an indication of what soil implement and soil tillage method will be needed. Obviously some expertise and experience are needed to interpret the visual soil properties correctly. During inspection of the soil profile, soil samples must be taken for analyses, especially to determine what kind of ameliorants such as lime, type of lime, gypsum and P will be needed. The number of profile pits will be determined by soil variability, but four pits per ha, i.e. a grid of 50 m x 50 m, will normally be adequate. More samples should be taken if the soil is highly variable.

PHOTO: ARC INFRUITEC-NIETVOORBIJ.

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