Nebraska irrigated corn and soybean yields reached their second-highest averages in history in drought-plagued 2012, but yields for their dryland counterparts were at their lowest averages in about 30 years, according to the US Department of Agriculture.
The U.S. Department of Agriculture – National Agriculture Statistics Service reported state average yields of corn and soybeans of 190 bushels per acre and 59 bushels per acre, respectively, under irrigation. That was second only to yields in 2009 for corn and 2011 for soybean.
But under dryland conditions, average yields statewide were 61 bushels an acre for corn and 25 bushels and acre for soybean, the lowest since 1983 for the former and '84 for the latter.
"The low dryland yields were not surprising, given that rainfall during the crop growing season did not exceed 10 inches at most locations -- about half of the rain amount in a typical year," said Patricio Grassini, research associate professor in the University of Nebraska-Lincoln's agronomy and horticulture department.
The 2012 irrigated corn yield average was 10 bushels above the 2011 yield and five bushels above the 2005-11 average.
The highest county averages were reported in south central Nebraska, ranging from 205-220 bushels, according to NASS.
It was the opposite story for dryland corn. A 59 bushel/acre average was 74 bushels below the 2011 average and 68 bushels below the 2005-11 average.
The highest county average dryland corn yields, in the range of 80-100 bushels/acre, were reported in counties on the east central and east south edges of the state and in two counties in south central Nebraska.
Nebraska statewide irrigated soybean yield in 2012 of 60.7 bushels/acre was only 0.4 bushel below the 2011 irrigated soybean average and 2 bushels above the past seven-year average (2005-2011).
The highest county-level average irrigated soybean yields, in the range of 66 to 70 bushels, were reported for counties in south central Nebraska.
For dryland soybeans, the statewide average yield of 25 bushels/acre was 23 bushels below the 2011 average, and 20 bushels below the past seven-year average (2005-2011). The highest county-level average dryland soybean yields, in the range of 32 to 38 bu/ac, were reported for counties in the east central and east south edges of the state and for two counties in south central Nebraska.