Photo credit: Neil Palmer (CIAT)

A new study published in the Journal Proceedings of the Royal Society Biology has found that the yields of organic crops are higher than previously thought, particularly when organic farmers use environmentally friendly farming techniques. Researchers from the University of California, Berkeley, carried out the largest meta-analysis comparison of organic and conventional crop yields to date, synthesizing results from 115 studies with over 1,000 observations. By including this large body of data and using a more rigorous statistical methodology, this study found that the gap in yields between organic and conventional was lower than had previously been reported, and that some organic management practices (such as multi-cropping and crop rotations) can shrink that yield gap even further, reducing the yield gap from 19 percent to only 8 to 9 percent.  Additionally, the study notes a bias in the direction of conventional agriculture in data from the literature comparing organic and conventional yields. This means that the yield gap reported by this study, which uses the most comprehensive available data, is probably overestimated and the true yields of organic are likely even greater. “The yield gap that we detected is actually surprisingly small when one considers the historic underfunding of research in organic agricultural management and in breeding of seeds for organic conditions,” said Professor Kremen, one the study’s authors. “Coupled with our finding that crop rotation and multi-cropping (two practices that are well known to build soil fertility and health, reduce pest and diseases, and improve water use efficiency) improve the organic-to-conventional yield ratio, we suggest that additional agronomic research and breeding for organic could further reduce the remaining gap, leading to environmentally friendly and productive agriculture.” The study authors conclude that “reducing the yield gap between organic and conventional agriculture (or more accurately, between biologically diversified versus chemically intensive farming systems) has the potential benefit of reducing the loss of biodiversity and ecosystem services often associated with conventional agricultural methods, and thus promoting a high-yielding agriculture that is relatively environmentally and wildlife-friendly compared with conventional systems.”