|Corn rootworm. Photo from Wiki Commons|
Corn rootworm ranks amongst the most expensive threats to US maize farmers. The invention of a GM crop which generates its own 'Bt' insecticide against the rootworm has been a great boon.
However, bolstered by biotech enthusiasm to sell as much as possible of its product, farmers' enthusiasm for reduced post-planting workload and costs, government enthusiasm for incentives to grow maize, and limited availability of alternative seeds, US agriculture has been channelled into planting the same Bt crop year-on-year.
And the rootworm have, inevitably, evolved resistance to that Bt toxin.
Aware that this puts US maize production on a slippery slope to increased and ever-increasing use of noxious pesticides, the Environmental Protection Agency (EPA) has made a "bold" proposal to require seed companies to force farmers to change their habits back to old-fashioned crop rotation.
Suggested efforts by industry could include legal agreements signed by farmers, and incentives to encourage non-growing of Bt maize.
To add leverage, the EPA is demanding that fifteen varieties of GM corn be re-registered by the biotech industry later this year along with outline plans for stemming insect resistance.
Neither the farmers nor the biotech industry like being told what to do.
Another erstwhile GM boon to farmers, herbicide-tolerant crops, are also collapsing in the face of over-use.
Glyphosate-based herbicides (such as Monsanto's 'Roundup') have been used, not only to clear away weedy competitors in fields of GM crops, but also to minimise tillage and preserve soil structure. Now there are so many glyphosate-resistant weeds around, farmers are resorting to old-fashioned weed control methods including high-intensity (soil destroying) tillage to bury the problem, cover-crops to smother the problem, and weeding the problem out by hand.
Failing to learn the lesson of the past, the EPA and US Department of Agriculture have approved the biotech industry's 'answer' to this rekindled weed problem: new GM crops resistant not only to glyphosate but also to a much older, more toxic weedkiller, 2,4-D.
US 'light-touch' agri-regulators seem to expect farmers and the biotech industry to solve the problems they've created for themselves. Unfortunately biotech industry 'agri-solutions' tend to involve ever more chemicals and GM crops, and farmer 'agri-solutions' now tend to involve asking the biotech industry what to do.
Glyphosate has now been classified as a probable carcinogen and comes in a formulation which attacks cell membranes: 2,4-D seems to have very similar properties . Perhaps the EPA might do better to persuade the biotech industry to get its farmers off the GM treadmill altogether.
 GLYPHOSATE IS A PROBABLE CARCINOGEN - May 2015
 2,4-D - EVERY BITE A KILLER - April 2011
- Jacob Bunge, Limits sought on GMO corn as pest resistance grows, Wall Street Journal 5.03.15
- Carey Gillam, EPA will require weed-resistance restrictions on glyphosate herbicide, Reuters, 31.03.15
- Carey L. Biron, U.S. Nearing Approval of Next Generation of Herbicide-Resistant Crops, IPS News, 2.05.14
- Paul Hollis, Conservation tillage systems threatened by herbicide-resistant weeds, Southeast Farm Press, 11.03.15