Ten years ago, few supermarkets stocked organic food, and those that did carried little more than some wilted lettuce and a basket of spotty apples — nothing to suggest that organic agriculture had a sparkling future. But now the future is here, and whole aisles of organic products in many stores command higher prices than food grown by conventional, intensive methods.

Researchers into organic methods have enjoyed a corresponding upsurge of interest in their work. Once relegated to the fringes of agricultural colleges and research stations, people who study composting and soil-organism biodiversity, for example, are now being taken seriously (see pages 792–798). Even the most intensive farmers are conscious of the need for farming methods that will be sustainable in the long term, and the research emphasis has shifted from maximizing yield to finding sustainable techniques. It is a moment to be savoured by proponents of organic agriculture and soil conservation, and presents an opportunity that must not be squandered.

Public discussions of organic farming, particularly in the news media, tend to be sharply polarized. Advocates insist that conventional farming exhausts the land and is unsustainable. Critics question the wisdom of farming with manure, and suggest that switching to less efficient methods is unethical when so many people in the world are hungry.

These debates tend to be heated in the scientific literature, too, with representatives of each point of view finding studies that back them up. Evidence can be produced to show that organic farms have higher yields or lower yields, produce more water-fouling nitrogen runoff or less. The resultant morass makes it tough for farmers and policy-makers to pin down the relevant facts.

This doesn't mean that the studies are necessarily flawed. It simply reflects the complexity of the systems being studied, and the number of variables involved. Straight comparisons of organic and conventional practice can often be misleading. Organic and conventional growers generally use different strains, for example, emphasizing pest resistance and yield, respectively. And organic farms change year to year, with yields improving and runoff decreasing over time as organic matter builds up and weed seeds disappear.

A better approach is to focus studies on particular issues of interest, such as soil conservation, nutrient retention and pest control. These should be done by collaborations between researchers who may have held differing views in the past. For too long, agricultural studies have tended to involve like-minded researchers and to be supported by a non-profit group, industrial company or government department that has an interest in the outcome. Now that such issues as soil conservation are acknowledged to be vital to all farmers, researchers with differing perspectives on the organic issue need to share their insights and seek out approaches that work.