(https://image.guim.co.uk/sys-images/Guardian/Pix/pictures/2011/11/15/1321368744564/A-wheat-field.-007.jpg)
Some 15 investigators have been dispatched to Oregon to find out how GM wheat seeds arrived in what was supposed to be a fallow field in the eastern part of the state. Monsanto had carried out field trials of the GM wheat in Oregon and 15 other states between 1998 and 2005, but abandoned efforts to market the strain.
Half of America's wheat is exported, and buyers in Asia and Europe were opposed to GM products. The last field trials in Oregon were grown about a decade ago. The company has not entirely given up on GM wheat, however. Monsanto has applications pending to test new strains of GM wheat at fields in North Dakota. (http://www.guardian.co.uk/environment/2013/jun/05/gm-wheat-oregon-field)
How and why this was discovered was quite funny:
Resistance to glyphosate (http://pmep.cce.cornell.edu/profiles/extoxnet/dienochlor-glyphosate/glyphosate-ext.html), a key ingredient in weed killers such as Roundup. The presence of Monsanto’s Roundup Ready gene (CP4) was the first clue as to whom the wheat belonged to. This is a specific indicator of the MON* series of crops, in this case MON71800.
American farmers have not raised GM wheat on a commercial basis. The major export markers of Europe and Asia do not want GM wheat due to reservations about genetic engineering. “Our customers have zero-tolerance for GM wheat,” said Wally Powell, president of the Oregon Wheat Growers League.
Monsanto currently blames sabotage by unknown Ecoterrorists. I call bullshit, someone did a improper disposal. (http://orgprints.org/9074/1/9074.pdf) In fact, the article ‘GM/non-GM wheat co-existence in Canada: Roundup Ready® wheat as a case study’ demonstrates such.
TL:DR version, GM genetic traits will contaminate other crops covertly. New herbicides, methodology and additional finical resources are required to prevent such.
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The result of Roundup Ready transgene movement in western Canada is that essentially all volunteer canola populations in western Canada contain some proportion of Roundup Ready volunteers. This is true even if Roundup Ready canola cultivars have never been intentionally planted in a given field. Farmers now cannot be certain of the herbicide tolerance status of their volunteer canola population. When Roundup Ready volunteer canola is present in a field, pre-seeding weed control in low-disturbance direct seeding systems requires the addition of another herbicide as well as glyphosate, adding cost and complication in the crop rotation because of the pre-seeding residue left by some herbicides (Van Acker et al., 2003). Farmers who choose to grow Roundup Ready canola balance the added costs and complications against the measurable benefits they receive from this technology. However, because of the ubiquitous presence of the Roundup Ready trait in volunteer canola populations, the added costs and complications in rotation are also borne by farmers who choose not to grow Roundup Ready canola (non-adopters).
The impact of gene movement depends upon the crop. For example, controlling Roundup Ready wheat volunteers in a low-disturbance direct seeding system would cost more than controlling Roundup Ready canola volunteers (Harker et al., 2003; Van Acker et al., 2003). If the transgene conferring glyphosate tolerance became ubiquitous in volunteer wheat populations in a manner similar to what we have witnessed in canola, then the cost associated with low-disturbance direct seeding systems in western Canada would rise significantly. This would threaten the economic viability of these systems and in turn threaten Canadian farmers' ability to capture the environmental, resource conservation and economic value of low disturbance direct seeding (McRae et al., 2000). In this manner, a production economics issue related to the movement of one trait within a crop species can become an environmental issue.