Organic agriculture fights back.

• Author: Ching, Lim Li

Organic farming largely excludes synthetic inputs--pesticides, herbicides and fertilizers--and focuses instead on biological processes such as composting and other measures to maintain soil fertility, natural pest control and diversifying crops and livestock. Organic agriculture gives priority to long-term ecological health, such as biodiversity and soil quality, contrasting with conventional farming, which concentrates on short-term productivity gains.

Organic farming has been denigrated for being less efficient in land use and having lower yields than conventional farming, and even accused of posing potential health risks.

But there are scientific studies, peer-reviewed and published, documenting organic agriculture's positive outcomes. Furthermore, certified organic production is just the tip of the iceberg. De facto organic farming is prevalent in resource-poor, agriculturally marginal regions where local populations have limited engagement with the cash economy. Farmers rely on locally available natural resources to maintain soil fertility and to combat pests and diseases. They are showing the way towards sustainable agriculture through sophisticated systems of crop rotation, soil management, and pest and disease control, based on traditional knowledge.

The charge that organic farming is lower-yielding is misleading. Studies simply evaluating the reduction or elimination of inputs in conventional systems may not accurately represent conditions in alternative systems. Furthermore, comparisons made when farms have just turned organic do not tell the whole story, as it takes a few years for yields to increase.

A study on conventional and alternative farming systems for tomatoes over four years indicates that organic and low-input agriculture produce yields comparable to conventional systems. Nitrogen (N) availability was the most important factor limiting yield in organic systems, and can be satisfied by biological inputs.

Another experiment examined organic and conventional potatoes and sweet corn over three years. Results showed that yield and vitamin C content of potatoes were not affected by the two different regimes. While one variety of conventional corn out-produced the organic, there was no difference in yield of another variety or the vitamin C or E contents. Results indicate that long-term application of composts is producing higher soil fertility and comparable plant growth.

A review of replicated research results in seven different US Universities and from Rodale Research Center, Pennsylvania and the Michael Fields Center, Wisconsin over the past 10 years showed that organic farming systems resulted in yields comparable to industrial, high-input agriculture.

* Corn: With 69 total cropping seasons, organic yields were 94% of conventionally produced corn.

* Soybeans: Data from five states over 55 growing seasons showed organic yields were 94% of conventional yields.

* Wheat: Two institutions with 16 cropping year experiments showed that organic wheat produced 97% of the conventional yields.

* Tomatoes: 14 years of comparative research on...