That's because grain prices also are strong, and also because cotton is an expensive and labor-intensive crop to raise.

WSJ: Farm Economy Bounces Back

In fact, raisins are the most labor intensive crop in North America.

NPR: Guest-Worker Debate: Human or Mechanical Labor?

Sugar cane, which is planted in the summer, is a water-intensive crop and farmers may shift to other crops temporarily, industry executives said.

WSJ: Drought to Hit Sugar Cane Output in Maharashtra

Corn, he concedes, is an energy-intensive crop, but Tumbleson says he may be better off than wheat or soybean farmers because corn is in just about everything we eat.

NPR: Energy Costs Drive Up Prices of Nearly Everything

Alternative livelihoods such as ecotourism and fish farming could provide an alternative to intensive crop farming, while better management of crops and irrigation and the adoption of alternative energy sources such as solar power would all contribute to environmental sustainability.

CNN: Growing deserts 'a global problem'

Organic methods, which rely on crop rotation, manure and compost in place of fertiliser, are far less intensive.

ECONOMIST: Ethical food