If the soil is uniform across your field, take 15 to 20 samples from random locations throughout the field. Combine these samples into one sample by mixing them in a plastic bucket
. If the soil is highly variable from one part of the field to the other, divide the field into smaller uniform areas and treat each of these areas as a separate field.
Take 15 to 20 samples from each area. Combine these as suggested above. Test each combined sample from each area separately. Separate test results will allow you to appropriately remedy the deficiencies of each subdivision within your field.
Indicators of variable soil include differences in soil appearance, texture, wetness or salt content. Avoid sampling close to lime or manure piles, animal droppings, freshly fertilized rows, low spots, fences, and roads.