How Good Were 2010 Soybean Yields in Illinois?

The Illinois state soybean yield of 51.5 bushels per acre for 2010 was a record high yield. Many counties also had a very good yielding year for soybeans, with 83 percent of the counties having actual yields above their respective trend yields, and 50 counties setting a record high yield. Five counties exceeded 60 bushels, the first year in which county yields exceeded 60 bushels per acre.

State Yields

The 2010 state yield in Illinois was 51.5 bushels per acre, the first Illinois state yield to break 50 bushels (all yield data are from the National Agricultural Statistical Service (www.nass.usda.gov)). Based on a linear trend from 1972 through 2010, the expected yield for 2010 was 47.7 bushels. The 51.5 bushel actual yield was 3.7 bushel above trend. Since 1972, only five years – or 12 percent of the years — had yields more than 3.5 bushels above trend: 1977 (4.3 bushels above trend), 1979 (4.5 bushels), 1985 (5.4 bushels), 1994 (4.6 bushels), and 2004 (4.8 bushels).

County Yields

Eighty-four out of 101 counties- or 83 percent – had actual yields above trend yields. Five counties had trend yields there were at least 10 bushels higher than trend yields: Bond, Boone, Lake, McHenry, and Moultrie counties. Thirty-five counties had trend yields between 5 and 10 bushels above trend yields.

The 2010 county yields were the highest on record for 50 counties in Illinois. Five counties broke 60 bushels: Piatt (63.3 bushels), Moultrie (62.8 bushels), Christian (60.5 bushels), Sangamon (60.4 bushels), and Macon (60.4 bushels) Counties. This was the first year in which county yields exceed 60 bushels per acre.

There were some counties that had yield below trend. These counties were located in extreme southern Illinois, in central Illinois along the Indiana border, and along the Mississippi River in central Illinois.