An Ecological Scare Story That's for the Birds
September 19, 2000
by Dennis T. Avery
BRIDGE NEWS September 7, 2000
CHURCHVILLE, Va.--The frenzied efforts of some "scientists" to gain fame and funding by pinning some eco-danger on biotech foods may have reached a peak last month at a British university.
A team at the University of East Anglia used a computer model to theorize that if every farmer used herbicide-resistant crop seeds to help eliminate all weeds, birds that eat weed seeds would starve.
The Financial Times reported this silliness under the headline, "Bird Numbers Under Threat From GM Crops." Birds find most of their weed seeds in the wildlands, pastures and field edges. Farmers have been killing the weeds in their crop fields for thousands of years, first with hand weeding, then with hoes and plowing, and most recently with chemical weedkillers.
The Financial Times might more accurately have printed a headline reading, "Bird Numbers Under Threat From Organic Crops." Trying to feed humanity from weed-choked organic fields would mean cropping two or three times as much land as we currently plant.
That would sacrifice perhaps 5 to 12 million square miles of wildlife habitat, starving billions of birds. We have this on the excellent authority of Alistair Leake, director of research for the Cooperative WholesaleSociety of England. The CWS farms about 80,000 acres of land under both conventional and organic systems.
Leake likes organic farming because of its high prices. However, he warned a British House of Lords hearing in 1999, "Generally, yields are much lower. On the basis of CWS results, a complete switch to organic farming would result in a 44 percent drop in U.K. wheat production...that translates into an annual shortfall of 5.1 million tones."
Lord Reay, who was chairing the hearing, responded, "To produce the same quantity of wheat (organically) you have to put under arable cropping a much greater amount of land. Is this not a negative effect on biodiversity?"
"Yes it does imply that," said Leake. "Of course, the solution to that would be for us to import." The planet cannot import food, however. Organic or conventional, someone must grow the food we eat, somewhere on the earth. The more land we farm, the more wildlife we displace.
"There is little difference in the numbers or the species diversity of birds between the two systems," said Leake. "It is the way that the uncropped areas, the hedges and edges, are managed rather than the farming regime itself which appears to have most influence on species diversity. Wildlife likes the 'unkempt bits' and organic farms are not necessarily likely to have more untidy areas than conventional farms."
Organic farms do have more weeds, however. Leake testified that "Looking in the crop itself, the organic system has a much greater density of weeds-wildflowers." Leake said his organic fields sometimes get so weedy the crops must be destroyed, since they would produce virtually no food, but would produce billions of new weed seeds to threaten the next year's crop as well.
Asked if this wasn't a costly penalty for organic farming, he said no--the government of the European Union pays farmers even if they lose their crops.
Leake candidly criticized organic farmers for using nasty but "natural" pesticides. "The use of copper and sulphur fungicide sprays seems inconsistent with the claim that organic agriculture is pesticide-free. On examination, the eco-toxicology of copper sulphate is undoubtedly more harmful and persistent than its conventional counterpart, Mancozeb."
Leake even provided a handy table, showing that the copper sulphate used by organic farmers is toxic to humans, very toxic to earthworms and fish, moderately toxic to birds and harmful to small mammals.
Mancozeb, in contrast, is rated "practically non-toxic" to humans, and has moderate to low toxicity for earthworms and fish, low toxicity to birds and no toxicity for small mammals. The synthetic fungicide is also far less persistent, breaking down in 6 to 15 days.
Copper sulphate persists beyond 20 years unless a crop such as potatoes takes it up. In that case, the copper sulphate enters the food chain!
Leake also noted "We (organic farmers) rely heavily upon ploughing to control weeds, which is very disruptive to soil communities; whereas (conventional farmers' use of) direct drilling with the use of herbicides is hugely beneficial to soil organisms."
Leake also criticized organic standards and inspection as being too narrowly focused against man-made chemicals. "So while the organic standards may attempt to ensure freedom from pesticide residues, the freedom of organic foods from vermin, mycotoxins and other contamination may be less certain."
Leake is acknowledging organic farmers are more likely to let their crops suffer rodent and insect damage, which leads to more fungal infections and more natural toxins in the food.
Organic farmers are also much more likely to put manure on their food crops, which can lead to contamination with dangerous pathogens such as the deadly strain of E. coli O157:H7.
Lord Reay asked Leake, "In your view organic produce is going to remain a niche market?"
"Indeed," answered the farm manager.
Dennis T. Avery is based in Churchville, VA, and is director of the Hudson Institute's Center for Global Food Issues.