Nitrogen, phosphate, and potash are essential in the production of crops used for food, feed, fiber, and fuel. Applied annually, most of these nutrients are absorbed by the crop, but when applied in excess, they can be lost to the environment through volatilization into the air, leaching into ground water, emission from soil to air, and runoff into surface water (see Nitrogen in Agricultural Systems: Implications for Conservation Policy, ERR-127, September 2011 for more information on these impacts). These losses can be reduced by adoption of best management practices (BMPs) that increase the nutrients' accessibility for plant use, enhance plants' ability to uptake nutrients, and more closely match nutrient applications with agronomic needs (see the topic on Crop and Livestock Practices).
Annual Fertilizer Consumption Has Become More Volatile Since 2004
Commercial fertilizer consumption increased rapidly before 1982 as more acreage was devoted to high-yield crop varieties and hybrids that responded favorably to more intensive fertilizer use. As global demand for grains grew, U.S. consumption of commercial fertilizers peaked at 24 million tons in 1981. When grain demand dropped in 1983, government Payment-in-Kind programs took a large amount of U.S. cropland out of production, reducing fertilizer consumption to 18 million tons. Commercial fertilizer use then trended upward, largely due to increased corn plantings. In 2004, growth in annual fertilizer use became much more volatile in the face of rapidly rising fertilizer prices, driven by rising energy and input material costs. Record fertilizer prices in 2009 reduced consumption to 18 million tons, a 24-percent decline from 2004. As fertilizer prices declined in 2010, consumption rebounded to 21 million tons, and increased to 22 million tons in 2011, mainly due to nitrogen consumption increase.
Nitrogen fertilizer use has increased more rapidly than phosphate and potash due to the development of seed varieties with more favorable yield responses to nitrogenous fertilizers. Corn--with many planted acres under intensive fertilizer application--accounts for around 40 percent of the U.S. fertilizer consumption.
Farmers are Increasingly Applying High Grade and Single Nutrient Fertilizers
U.S. farmers are moving away from using multiple-nutrient fertilizers toward using single-nutrient fertilizers or fertilizers with a high level of nutrient concentration. Single nutrient fertilizers with high nutrient concentration allow farmers to apply precise amounts of a specific nutrient for plant use at the least cost. From 1960 to 2011, the share of mixed NPK fertilizers steadily declined from 35 percent to 20 percent of applied nitrogen, and ammonia nitrate (34-0-0) declined from 15 percent to 2 percent, while the share of solid urea (46-0-0), which has the highest percent of N by weight among solid nitrogen fertilizers, increased from 2 percent to 22 percent. Share of nitrogen solutions (31-0-0) increased from 7 percent to 27 percent. Anhydrous ammonia, the dominant nitrogen fertilizer product for many years, has declined in recent years, replaced by urea and nitrogen solution largely because their low material and field application costs. Furthermore, nitrogen solutions increasingly become the preferred nitrogen fertilizer product because of their favorable chemical and physical characteristics that allow nitrogen solutions to provide more accurate, steadily and uniformly supply of nitrogen to plant, to carry herbicide and micronutrients, and to mix with irrigation water. Increasing use of high concentration phosphate and potash fertilizers also occurred. From 1988 to 2010, MAP’s (11-53-0) share of the U.S. phosphate consumption increased from 9 percent to 42 percent, exceeding DAP (18-46-0) in 2007. Potassium chloride (0-0-(60-62)) is the largest potash fertilizer material used for crop production; its share increased to 73 percent in 2011.
U.S. Nitrogen and Potash Consumption Increasingly Depend on Imports
Imported supplies of nitrogen have accounted for an increasing share of U.S. nitrogen consumption in recent years. Fixed nitrogen production capacity in the U.S. means that increased consumption of nitrogen fertilizer depends on imports, even though the U.S. supply of natural gas--a critical component in the production of nitrogen fertilizers--has been increasing recently. In 2002, net imports accounted for 19 percent of U.S. nitrogen consumption. By 2011, net import's share of U.S. nitrogen consumption had increased to about 50 percent.
The supply of potash in the U.S. has historically depended largely on imports. More than 85 percent of potash (K2O) supply was from imports in calendar year 2011. Because domestic production capacity is limited and has generally declined over time, any increase in potash demand must be met by imports.
In contrast, U.S. phosphate (P2O5) supply is mainly from domestic production, which provides over 90 percent of domestic use. The U.S. is the second largest producer of phosphate fertilizers in the world (after China), and exported more than 41 percent of its production in 2011.
Fertilizer Prices Rose Rapidly and Became More Volatile in Recent Years
From 1960 through 2002, both fertilizer prices paid and crop prices received by farmers increased in tandem at a fairly modest rate. Since 2003, annual fertilizer prices paid by farmers have increased rapidly--generally much faster than increases in crop prices received by farmers--and have become more volatile. Fertilizer price increases through 2008 were largely driven by high energy prices and high input material costs (see Impact of Rising Natural Gas Prices on U.S. Ammonia Supply, WRS-0702, August 2007; Factors Contributing to the Recent Increase in U.S. Fertilizer Prices, AR-33, February 2009). In response to record fertilizer prices in 2008, farmers reduced their use of fertilizers, contributing to a large decline in fertilizer prices through 2010. But fertilizer prices have started to move up once again, driven by strong domestic demand for plant nutrients due to high crop prices, and limited domestic production capacity.