3.2.2. Grid soil sampling
Grid soil sampling provides an initial base of information for
developing variable rate applications plans. This technique uses a
systematic method to reveal fertility patterns and hard pans. After
the maize harvest 2008, soil samples were collected in systematic
grid (32 in zone 2, 32 in zone 3, 2 in zone 1 and 2 in zone 4) providing
location information that allowed the data to be mapped as shown
in Fig. 3. Grid soil sampling aimed mainly at identifying the current status of nutrients and producing maps of potential nutrient
requirements.