Nebraska Irrigated and Rainfed Corn Yield Trends
- Irrigated corn yields are rising at a rate of 2.1 bu/ac year.
- Rainfed corn yields are also rising but at a slower rate of 1.5 bu/ac year.
- USA yields are rising at a rate of 1.7 bu/ac year (about 0.2 bu/ac year faster), but some of the USA corn production occurs in irrigated regions.
- Large season-to-season fluctuations occur in rainfed corn yields, due to unexpected annual variance in rainfall amounts and distribution.
- Irrigated corn yields are predictably high each year, so investing in yield-improving technological inputs are less risky & potentially more profitable.
- Such investments are likely why the yield difference between irrigated and rainfed production is widening, on average, by about ½ bu/ac per year
Nebraska Irrigated and Rainfed Corn Acreage Trends
- In 2012, 5.78 million irrigated acres (46%) and 3.33 million rainfed acres (54%) of corn were grown in Nebraska.
- Irrigated acreage, which was about 5 million acres in 1980 (32 years ago), has grown only modestly since then to 5.57 million acres in 2012.
- In contrast, rainfed acreage doubled from 2 million acres in 1980 to 4 million acres in 2011 (less harvested acreage in 2012 - severe drought year).
- In the past 15 years, the irrigated fraction of the State’s total corn acreage has routinely about 60%.