Which soil test results are essential for developing a nutrient management plan?

The essential soil test results for developing a nutrient management plan focus on the soil's chemical properties, which directly influence nutrient availability for crops. Soil pH is crucial because it affects the solubility of nutrients and their uptake by plants. For instance, most crops thrive in a pH range of 6 to 7; outside this range, nutrients like phosphorus can become less available.

Macronutrient concentrations, such as nitrogen, phosphorus, and potassium, are vital for formulating a nutrient management plan because these nutrients are required in larger quantities for plant growth. Testing for levels of these macronutrients allows for appropriate recommendations regarding which fertilizers to apply and in what amounts.

Micronutrient levels, although needed in smaller quantities, are equally important as deficiencies or excesses can significantly affect crop health. Essential micronutrients include iron, zinc, and manganese, among others. Understanding their concentrations helps ensure that crops receive a balanced nutrition profile, promoting optimal growth and productivity.

The other options, while related to agricultural practices, do not focus on the chemical characteristics of the soil necessary for nutrient management. Organic matter, water retention capacity, and soil temperature are important for soil health and fertility (the first choice), pest populations and crop history (the third choice