... used in oil-fed agriculture is consumed in transporting the finished product. There is oil consumed in producing the fertilizers, herbicides and pesticides, oil consumed in breaking the ground for planting, sowing, and harvest.

Of course, for drying after the harvest its more likely to be natural gas.

About the only time our current agricultural system doesn't use oil is when the farmer is in the house in the evening, consuming coal or natural gas fired electricity.

Indeed, for all of the hoo hah about ethanol driving up corn prices, I saw a claim floating around cyberspace that the major factor driving up corn prices were oil price spikes.

I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.