Corn farmers fret over fertilizer costs :: Yahoo! News

Higher oil prices have meant higher fertilizer prices - chemical fertilizers are derived from oil. This article provides a nice example of how the higher cost of fertilizer influences farmer's decisions to substitute between production fertilizer-intensive crops like corn into less fertilizer-intensive crops.

The Oil Drum in Philly points out the irony of using plastics derived from corn in place of plastics derived from petroleum.