Soil Fertility

Soil Sampling

Soil sampling is needed to determine soil nutrient needs and optimize fertilizer use and to assess soil variability across the field. See these guides for further information:

• Guidelines for Soil Sampling (G1740)
• Soil Sampling for Precision Agriculture (EC154)

Nebraska Fertilizer Nitrogen Recommendations

• The Long View of Nitrogen Recommendations from Nebraska Extension
• A Bibliography of Nitrogen (N) Related Publications from the UNL Soils Faculty (1952-2019)

Nutrient Deficiencies

• Key to Nutrient Deficiencies in Soybean 
• Key to Nutrient Deficiencies in Wheat and other Small Grains
• Key to Nutrient Deficiencies in Corn and Sorghum

Plant symptoms can be used to differentiate and identify crop nutrient disorders. Symptoms of nutrient deficiency vary with variety, growing conditions, and plant age. Similar symptoms may be caused by other abiotic or biotic stresses. Use these symptom keys to help identify nutrient disorders observed in Nebraska corn and sorghum, soybean, or wheat and small grains.

For more information on these and related topics, see the UNL Extension publication, Nutrient Management for Agronomic Crops in Nebraska, EC155, available online, or in soft cover through your local Extension office.

Soil Management Software

• Maize N — A program for estimating corn N needs and in-season losses.
• Hybrid-Maize Model - A computer program for simulating corn growth and yield
• Corn Nitrogen Recommendations Calculator
• Winter Wheat Fertilizer Calculator. Use this calculator in conjunction with Fertilizing Winter Wheat, Extension Circular EC 143 
• 2012 Nebraska P-Index (Excel): Instructions at Nebraska PI Documentation and Troubleshooting Guide
• Nitrogen Loss Assessment Tool (N-LAT) for Nebraska: Download this Excel tool used to estimate average N loss to leaching, volatilization, denitrification, and nitrous oxide emission for corn and soybean production. See Background Information and Users Guide for N-LAT (NebGuide G2249).
• The Value of Manure:  A simple calculator (Excel) for estimating the value of manure. Corresponds with the NebGuide G1519: Calculating the Value of Manure for Crop Production
• Whole Farm Nutrient Balance(.xls) Instructions: Estimating a Whole Farm Nutrient Balance EC189
• Nutrient Inventory (Excel) Instructions: Manure Nutrient and Land Requirement Estimator EC190
• Fertilizer Use Optimization in Africa