Nebraska Irrigated and Rainfed Corn Yield Trends
- In 2016, irrigated and rainfed corn yields averaged 199.9 bu/ac and 147.2 bu/ac, respectively. The US average corn yield was 174.6 bu/ac.
- Nebraska irrigated corn yields are increasing at a rate of 2.152 bu/ac per year.
- Nebraska rainfed corn yields are also increasing, but at a slower rate of 1.735 bu/ac per year.
- US corn yields (mostly rainfed) are rising at a rate of 1.825 bu/ac year, which is not much more than the foregoing Nebraska rainfed corn rate.
- Large season-to-season fluctuations occur in rainfed corn yields because of annual variance in rainfall amounts and distribution.
- Irrigated corn yields are predictably high each year, so investing in yield-improving technological inputs is less risky and potentially more profitable.
- Such investments are likely why the yield difference between irrigated and rainfed corn production in Nebraska is widening on average by 0.42 (about 4/10) bu/ac per year.
Nebraska Irrigated and Rainfed Corn Acreage Trends
- In 2016, 5.58 million irrigated acres (58%) and 3.97 million rainfed acres (42%) of corn were grown in Nebraska.
- Since 1980 irrigated corn acreage has increased by about 580,000 acres.
- Since 1996 irrigated corn acreage has fluctuated between 4.6 and 5.8 million acres.
- Rainfed acreage, however, has doubled from about 2 million acres in the 1980s to almost 4 million acres in the last five years.
- It is of interest to note that the irrigated percentage of all corn acreage has declined from a high of 72% in 1981 to just 58% in 2016. This is primarily due to a doubling of rainfed corn acreage as well as a gradual replacement of continuous corn production with a soybean-corn rotation in many Nebraska irrigated fields.
- The 2007 bump in irrigated corn acreage was due to a temporary shift of soybean acreage to corn acreage relative to producer anticipation in the spring of ethanol-driven higher corn prices.