They did pretty well creating a wasteland without atomic weaponry. 460 square miles of France in 1918 were declared "Completely devastated. Damage to properties: 100%. Damage to Agriculture: 100%. Impossible to clean. Human life impossible" (https://en.wikipedia.org/wiki/Zone_rouge). Hundreds of tonnes of unexploded munitions are still unearthed in the soil of Belgium and France every year; hundreds of people have been killed or injured by them.(https://en.wikipedia.org/wiki/Iron_harvest).