Farmers pay a lot of money for nitrogen (N) fertilizer, especially on corn and wheat but also vegetable crops like tomatoes, pickles, melons, sweet corn, etc. Most N fertilizer is produced from 200 plants world wide using the Haber-Bosch process. Natural gas or coal is used with atmospheric N using high pressure and high temperatures. The coal or natural gas is a source of hydrogen while the atmosphere supplies the N to produce ammonia (NH3). About 96% of the N fertilizer is produced this way but it also has high greenhouse gas emissions, methane and carbon dioxide. The need for N fertilizer is currently about 100 billion tons per year. The atmosphere is a natural source of N at 78%. Worldwide, there may be 4,000 trillion tons of total N atmospheric worldwide or about 34,000 tons of N/acre. Almost all of this N is in in the wrong form for plants. However, lightning can fertilize our crops adding 1 to 50 pounds (lb) of natural N per acre. Lightning converts nitrogen molecules with high ...

  Keeping soil nitrogen (N) and phosphorus (P) available and on the land is every farmer’s goal. If a farmer is paying for fertilizer, they want the plant to use it. From an environmental standpoint, N and P that leaches or runs off is bad for water quality. Finding ways to tie up N and P and keeping it on the land is good for everyone. The best way to keep nutrients in the soil is to keep the nutrient available but not soluble. Available nutrients can be used by soil microbes and then transferred to plant roots. Two problems occur with soluble nutrients. First, soluble nutrients flow with water and may either leach or runoff the soil. Second, in dry soils, soluble nutrients are not readily available. Nitrogen in the form of nitrates (NO3 - ) has a negative charge. Soluble reactive phosphorus (SRP) or orthophosphate (PO4 3- ) also has a negative charge as do clay particles. Since negative charges repel each other, these elements tend to be soluble and flow with water. Any organic s...

  Crop prices are high but fertilizer prices are rocketing even higher. Farmers are looking for ways to lower their fertilizer bill, especially on nitrogen (N). Almost all N is processed by soil microbes before being plant absorbed. About 85% of N is used to form about 20 amino acids which are converted to proteins and enzymes with about 10% of N used in plant genetics (DNA, RNA). Optimizing N fertilizer is critical.  University recommendations on N has changed over the years. University N research in the 1950’s advocated heavy N fertilizer because yield increased as N application increased?? N was relatively cheap and no researcher wanted farmers to lose yield as extra N was a cheap fertilizer insurance policy. That caused a few issues with water quality, so universities adjusted their N rates over the years. About 10 years ago, universities re-examined that original data and found little direct relationship between higher corn yields and higher N rates. The relationship betw...

  As crop prices increase, generally fertilizer prices increase as well. Farmers who are booking nitrogen (N) for next year are paying at least twice as much. N use efficiency is critical as farmers try to cut back on N usage while attempting to maintain crop yields. Building soil organic matter (SOM) and improving soil health improves N use efficiency. Soil health and regenerative farming systems develop healthy soils with robust microbial communities that recycle soil nutrients efficiently to meet a crop’s nutritional requirements. In healthy systems, photosynthesis is maximized which produces large volumes of soil carbon as a food source for the soil biology. The soil biology then recycles those soil nutrients to the plant as plant available nutrients. Keeping soils high in SOM or carbon are a key factor in buffering N and keeping it plant available (Larry Phelan). Inorganic N fertilizers are usually applied as salts which can be damaging to plants. “Inorganic” means it does not...

June is a busy month as farmers finish up planting, fertilizing, and spraying crops. For corn nitrogen (N), farmers have several options. Many farmers side-dress anhydrous nitrogen to corn. Anhydrous is a concentrated source of nitrogen, 82% by weight while liquid forms of N can be 28-32% or as high as 46%. Ammonia is usually the most economical, however, since it is stored at low temperatures (-28OF) with internal pressures of 250 psi , its more dangerous to apply. Anhydrous is often applied in the fall or early spring with a N stabilizer, getting at least a portion of their N applied, before spring or early summer rains prevent timely fertilizer application. Advantages include applying N fertilizer during a slack time period and it is generally cheaper and the most economical. Soil bacteria can easily convert ammonia into nitrate. Generally, corn like to take up N as both ammonia and nitrate. Nitrate forms of N promote growth while ammonia forms promote yield. As the season progress,...

After a dry summer, reduced corn yields generally results in excess soil nitrogen (N) and excess N leaching in the fall, winter, and spring. Most farmers fertilize for maximum yields and hope that the weather cooperates. When corn yields are reduced due to drought, the excess N that was applied is often lost through leaching when the rains return or it may be lost to the atmosphere as ammonia gas under saturated soil conditions through denitrification. Soil N runoff is lost at 100X higher rates than soil phosphorus and N is a major pollutant in Lake Erie and the Mississippi River. Keeping nitrogen in the soil should be a major goal of every farmer, so keeping N in a form that is both plant available but not soluble would be a great accomplishment. Microbially bound N is both plant available but also not soluble. When soils get dry, N is often not plant available but when these soils finally get wet, the soluble N can be lost by leaching or denitrification. The best way to reduce these ...

The Tri-State Fertilizer Guide gives the following recommendations on corn nitrogen application. The timing of nitrogen (N) fertilizer applications is an important factor affecting the efficiency of fertilizer N because of leaching and denitrification. Denitrification occurs when nitrate N (NO3 - ) is present in a soil and not enough oxygen (O2) is present to supply the needs of the bacteria and microorganisms in the soil. If oxygen levels are low, microorganisms strip the oxygen from the nitrate, producing N gas (N2) or nitrous oxide (N2O), which volatilizes from the soil. Three conditions that create an environment that promotes denitrification are wet soils, compaction and warm temperatures. Timing N applications to reduce the chance of N losses through these processes may increase the efficiency of fertilizer N use. Ideally, N applications should coincide with the N needs of the crop. This approach requires application of most of the N requirement for corn during a period 6 to 10 w...