Sorghum is a tough plant that tolerates hot, dry climates. Its fist-sized head is a common sight in the Ethiopian Highlands, in good years.

One of the many injustices of the food system is that some parts of the country can produce surpluses - but don't. The problems are:

• In good times, crop prices are low so there is little incentive to grow more.
• In bad times, there is no surplus, so food aid is needed.
• The poor road network hinders movement of produce.

Possible solutions include:

• In good times, subsidised higher prices stimulate a surplus, which is stored.
• In bad times, the subsidiser recoups costs by selling stored harvests at an appropriate price; reliance on food aid is reduced.
• Improved roads encourage movement of produce.