Grid sampling is offered by many companies involved in Precision Farming.
Research has concluded that grid sampling requires much finer grid densities than used commercially to produce accurate nutrient maps.
By taking 16 sub samples around each grid point on a 15m radius circle only 5% of the field is represented in the soil sample.
If the arable sector is going to capitalise on the potential benefits of precision technology then it is vital that an understanding of the causes and extent of within field crop variability are obtained. Yield maps, for example, demonstrate the effect rather than the cause of in-field variability.
Precise Nutrition uses soil electro-conductivity to generate finely detailed and highly accurate soil maps directly related to crop nutrition and the factors affecting crop production. Precise Nutrition can be used for:

The map below shows how Precise Nutrition defines the changes in soil characteristics across a field.
The field has been zoned and each zone is soil sampled using at least 16 sub-cores to produce a representative sample of that zone.
This information combined with cropping and management data is used to produce variable application files compatible with all major UK GPS equipment.