Features

• Sample points are chosen very closely to crop performance
• Ability to seek out problem areas that may otherwise have been missed
• Ability to scout points in the growing crop
• Sound agronomy investigations can identify limitations to growth - eg weed, plant population, drainage etc
• May identify factors affecting yield that are limiting which may not be nutritional
• Yield data can be used to for a nutrient replacement policy - fixing costs of production

Limitations

• Field coverage may be less than grid sampling
• Yield map data needs to be from a ‘normal’ year or ideally from a few years to get a good average field performance
• Many reasons for poor yield, pest damage, drainage, etc. as having yield differences. It is important that the low, medium, and high areas are sampled to get a handle on the nutrient status of all areas