With fertilizer being scarce and/or expensive there has never been a better time to fine-tune fertilizer use.
Jim Camberato


Fertilizer rate decisions have more potential impact on profits when soil test levels of a nutrient are deficient, because yield can be decreased by nutrient deficiency to an extent that offsets the savings of reduced fertilizer rates.
This report summarizes corn yield response to fertilizer nitrogen (N) rate in field-scale trials conducted
around the state of Indiana since 2006.

Phosphorus (P) and potassium (K) fertilizer prices have increased dramatically in recent months. If you cannot afford all the fertilizer P and K you think you need or there is not enough fertilizer to be had, you might want to prioritize their use on your farm. The key to prioritizing P and K use is to have recent soil test information for your fields. Top Priority: If soil test levels are below the critical level (Figure 1, Table 1) then crop yield response to added P and/or K might occur. These low testing fields or areas in a field should be given the highest priority for fertilization. The further the soil test is below the critical level the more likely yield will increase with application of that nutrient and that yield increase will likely be larger. The fertilizer application rates recommended for soil tests below the critical level are designed[Read More…]

To minimize the loss of nitrogen (N) from fall-applied anhydrous ammonia (AA), seal the application
slot, avoid applications on poorly-drained or excessively well-drained soils, wait till soil
temperatures approach freezing, and use a nitrification inhibitor.
A recent article1 in Progressive Farmer over viewed research showing yield reductions attributed to potash (0-0-60, KCl or MOP) applications in corn (North Dakota) and soybean (Minnesota and Indiana).

Low soil moisture and compaction slow crop uptake of potassium (K), often resulting in K deficiency.

Although nitrogen (N) fertilizer can be costly, it is needed to optimize profit in Indiana cornfields. Applying too little N reduces profit by reducing grain yield. Too much N does not return value and can also damage the environment.

Sulfur (S) deficiency has become more common in Indiana with reduction in atmospheric deposition of S arising from coal-fired power plants.

Light green alfalfa in the background of the photo was adequate in all nutrients except S which was 0.14% – well below the critical level of 0.25%.
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