Where was the epicenter of the 2012 drought?
The 2012 drought thoroughly choked the Cornbelt, and particularly states that were needed to produce a good crop. For the corn yield, the greatest damage extends from eastern Kansas to southwestern Indiana. For the soybean yield, the worst damage was limited to eastern Kansas. The early reports of yield from Crop Reporting Districts indicate the impact of the drought was the most widespread during the corn pollinating season in early July, but with the later reproductive calendar for soybeans, the area of the worst drought had moved further to the west and had tightened in its scope. Late summer rains in Indiana were particularly important to the soybeans in that state, as they were across northern Illinois and southern Missouri.
Source: Farmgate Blog