What is one guideline for soil sampling regarding depth?

Collecting soil samples from the top 15 cm is considered a standard guideline because this depth typically reflects the zone of active root growth and nutrient availability for crops. The 15 cm depth is ideal for assessing nutrient levels and soil conditions that directly influence plant health and productivity.

This depth corresponds to the area where most nutrient uptake occurs, facilitating effective nutrient management decisions based on the soil’s nutrient status. Sampling beyond this depth, such as the entire soil profile or at a greater depth, may not provide as accurate a representation of the nutrients accessible to most crops, which primarily operate within the top layer of soil.

Keeping the sampling depth to 15 cm ensures that the results are relevant to the current growing conditions and allows for better-informed management practices aimed at optimizing crop yields and maintaining soil health.