The European Union was formed to help war-ravaged countries beat swords into ploughshares. So successful has it been in that enterprise that it is urging its farmers to swap their ploughs for drills, to preserve the Continent's near-exhausted topsoil.

Fifty years of intensive agriculture have taken their toll. Europe's 25 member states lose 250m tonnes of soil a year to erosion, half a tonne per head of population.