THE extraordinary rainstorms last June caused catastrophic soil erosion in the grain lands of Iowa, where there were gullies 200 feet wide. But even worse damage is done over the long term under normal rainfall  by the little rills and sheets of erosion on incompletely covered or denuded cropland, and by various degradations resulting from industrial procedures and technologies alien to both agriculture and nature.

Soil that is used and abused in this way is as nonrenewable as (and far more valuable than) oil. Unlike oil, it has no technological substitute  and no powerful friends in the halls of government.

Agriculture has too often involved an insupportable abuse and waste of soil, ever since the first farmers took away the soil-saving cover and roots of perennial plants. Civilizations have destroyed themselves by destroying their farmland. This irremediable loss, never enough noticed, has been made worse by the huge monocultures and continuous soil-exposure of the agriculture we now practice.

To the problem of soil loss, the industrialization of agriculture has added pollution by toxic chemicals, now universally present in our farmlands and streams. Some of this toxicity is associated with the widely acclaimed method of minimum tillage. We should not poison our soils to save them.