Today we are proud to bring you Robert Paarlberg (who recently published Starved For Science) in conversation with Pamela Ronald (author of Tomorrow’s Table). These two experts will be debating how to best ensure a safe food supply with the least amount of damage to the environment. This is the first part of the series which we will be publishing all week, so be sure to come back and check out their exchange.
One of the nicest observations in your book, Tomorrow’s Table is that the standards used by ecological agriculture, and even by some counter-cultural “small is beautiful” economists like E. F. Schumacher, would actually seem to favor using genetic engineering in agriculture. Reduced spraying of pesticides, reduced tillage of the soil, and reduced burning of diesel fuel are all benefits to sustainable farming that current applications of genetic engineering can help provide.
We certainly agree that modern day conventional farming falls well short of being environmentally sustainable, yet I do not see the adoption of modern productivity-enhancing technology as the source of this problem. In the United States over the past six decades total farm output has doubled, yet thanks to much higher yields (made possible by improved seeds and more fertilizer) the total land area devoted to farming has actually declined by 25 percent. On a per capita basis, the total land area devoted to farming in America has actually declined by 50 percent since 1920, thanks to high-input science-intensive farming. This indicates much less pressure on the natural environment.
The uptake of modern farming techniques has also brought landscape protection benefits in the developing world. In 1964, India had been producing 12 million tons of wheat on 14 million hectares of land, but then – thanks to the high yields of the Green Revolution – India was able by 1993 to increase its wheat production nearly four-fold while increasing its cropped area by only 60 percent. To have produced this much wheat before the Green Revolution had increased yields would have required bringing much more land under the plow. In effect, the Green Revolution allowed India to meet its rapidly growing food needs without having to plow an additional 36 million hectares of cropland. M. S. Swaminathan, the Indian plant scientist who led the local effort to develop the new seeds concluded, “Thanks to plant breeding, a tremendous onslaught on fragile lands and forest margins has been avoided.”
Modern agriculture does entail much heavier chemical use – both fertilizers and pesticides – and this does damage the natural environment. Yet I would propose reducing this damage by bringing more science into farming, not less. Following the publication in 1962 of Rachel Carson’s Silent Spring, the first generation of particularly damaging farm chemicals such as DDT were replaced with less toxic and less persistent alternatives. Also, farmers learned to reduce chemical use by purchasing new crop seeds with greater resistance to insects and disease, and by moving toward far more precise fertilizer application methods, including satellite-based GPS systems that permit what is called “precision farming.”
Compared to modern farming, would a switch to organic farming result in less damage to the natural environment? In terms of landscape protection, the answer is no. Organically grown field crops generally have a lower yield per acre and they must be fertilized with systems that require more land for animal pasture or for cover crops (to be plowed under as “green manure”), so organic farming has a larger footprint on the land per unit of production than conventional farming. For example, in Europe the yield in organic systems compared to conventional is 68 percent lower for cereals and 73 percent lower for potatoes. Consequently, if Europe tried to feed itself organically it would need an additional 28 million hectares of cropland, equal to all the remaining forest cover of France, Germany, Denmark, and Britain combined. The prohibition in organic farming against any use of synthetic herbicides also has adverse environmental impacts, as it tends to block the use of no-till farming practices, which are rated as superior along all environmental criteria. A strict adoption of organic farming also makes environmentally sustainable agriculture more difficult because it rules out the use of genetically engineered crops, such as those that help farmers controls weeds and insects with fewer chemical applications and less soil tillage.
So, I like your ecological agriculture goals a great deal, but I worry that some of the technology restrictions imposed by organic farming are actually barriers to achieving those goals. Thanks for sharing your ideas, and once again I am enjoying your book a great deal.
Thanks for making the important point about the impact of farming on wild lands. As you indicate and I agree, high-input science- intensive farming has spared large amounts of land from the plow.
The problem is that much of the high yield achieved here in N. America is dependent on synthetic inputs such as pesticides and fertilizers, which are costly and can degrade the environment.
So what are we to do? Should we abandon modern farming practices? I agree this would be a dismal plan. As you point out in your thought provoking book Starved for Science, we have already carried out this experiment in Africa. Poor African farmers have no improved seed, no chemical fertilizers and no irrigation. Nor have they adopted the modern organic farming approaches of crop rotation and cover cropping. They are suffering as a consequence. As you say “Their meager crops provide less than a dollar a day. Many are malnourished.”
I also agree that expanding the number of organic farms cannot be the sole approach. Although organic farms support higher levels of biodiversity than conventional farms because they do not use synthetic pesticides, their yields are generally less. In some cases organic farming can yield as much as conventional agriculture; in other situations, especially under conditions of environmental stress or disease epidemics, organic farms do not yield as much as conventional farms. And because the biodiversity value of farmland generally declines with increasing yield on a given piece of land, even organic farms usually host far fewer species than do original pristine ecosystems. What this means is that even if we convert ALL of agriculture to high yielding organic farms (now only less than 3% in the United States), we still need to increase yield if we want to spare land, protect wildlife and feed the growing population.
Although it is true that organic farms are fertilized with systems that require more land for cover crops (to be plowed under as “green manure”), it is not so clear that organic farming ultimately will have a larger footprint on the earth per unit of production than conventional farming, especially if we consider the impact of global warming. That is because cover crops also have other critical roles. They help suppress weeds, deter the build up of insect pests, and add organic matter to the soil. This added organic matter enhances microbial activity and builds soil structure. Cover crops are benefiting growers and consumers, but in indirect ways. Furthermore, we must consider energy costs and global warming. With the cost of synthetic fertilizer increasing everyday because of the energy needed to produce it, we clearly need to adopt approaches that do not rely solely on this approach to foster soil fertility. This is especially true in Africa, where farmers do not have cash to buy synthetic fertilizers.
It is clear that for organic agriculture to be successful in feeding the world, huge changes will be needed: recycling of organic waste back to farms for nutrients, development of crop varieties with enhanced tolerance to pests and stresses, and reduced meat consumption so that more of the food crops can go to humans rather than animals.
I agree that part of the solution is to bring more science into farming, not less. This includes development of improved seed as well as improved methods of farming. Scientific research has significantly advanced and refined conventional and organic agriculture. Some practices have been validated and others discarded, new techniques have been developed. More importantly, the increasing involvement of university scientists has ensured that farming practices are science-based and effective. Most farmers (conventional or organic) want to use the most powerful technologies available to create an environmentally friendly, sustainable, and high-yielding farm.
This raises the question of whether GE varieties can help forge a future sustainable agriculture. Both conventional and organic farmers rely on genetically diverse and improved crop varieties to increase their yields, and I see no reason why GE seed should be treated differently. I like to think Rachel Carson would also agree. After all, in 1962 she said:
“A truly extraordinary variety of alternatives to the chemical control of insects is available. Some are already in use and have achieved brilliant success. Others are in the stage of laboratory testing. Still others are little more than ideas in the minds of imaginative scientists, waiting for the opportunity to put them to the test. All have this in common: they are biological solutions, based on understanding of the living organisms they seek to control, and of the whole fabric of life to which these organisms belong. Specialists representing various areas of the vast field of biology are contributing—entomologists, pathologists, geneticists, physiologists, biochemists, ecologists—all pouring their knowledge and their creative inspirations into the formation of a new science of biotic controls.”
Isn’t GE as exactly the kind of biological approach that she was hoping for? GE has lead to the development of pest resistant and high yielding crops, thus reducing the application of pesticides on conventional farms and increasing yield.
What we need is a successfully blend of two important strands of modern agriculture – genetic engineering and organic farming. If we rely on GE seed alone, without introducing the most productive aspects of organic agriculture such as crop rotation, we will not be able to maximize the benefits from GE.
For example, the use of Bt cotton in China, India and the US has dramatically reduced the amount of pesticides in the environment and enhanced yield. Yet Bt only kills caterpillars of some species, so it cannot be a stand-alone solution for general insect control. In fact, after seven years of pesticide reductions in Bt cotton fields in China, populations of other insects increased so much that farmers had to resume spraying certain insecticides. By contrast, organic farmers can control these secondary pests by introducing beneficial insects that feed on the pests and by rotating crops to reduce the overall pest populations. Furthermore, there is evidence that overuse of Bt (whether sprayed by organic farmers or engineered directly into the crop) will accelerate the development of pests resistant to Bt. By integrating crop rotation practices or refuges for the insects (an important strategy of organic farmers) there is less pressure on the insects to evolve resistance to GE crops.
Well, this email has gotten overly long. Thanks for reading it. I look forward to more discussions soon.
Featured Image Credit: ‘Vegetables, Garden, Harvest’, Photo by jill111, CC0 Public Domain, via pixabay.