Genetically modified foods: good news, bad news

The National Research Council has a new study out evaluating the benefits of GM (Genetically Modified) foods: Impact of Genetically Engineered Crops on Farm Sustainability in the United States.  The blurb about the book gives the good and bad news (which is which depends on how you interpret it):

Since genetically engineered (GE) crops were introduced in 1996, their use in the United States has grown rapidly, accounting for 80-90 percent of soybean, corn, and cotton acreage in 2009. To date, crops with traits that provide resistance to some herbicides and to specific insect pests have benefited adopting farmers by reducing crop losses to insect damage, by increasing flexibility in time management, and by facilitating the use of more environmentally friendly pesticides and tillage practices.

But then it continues:

However, excessive reliance on a single technology combined with a lack of diverse farming practices could undermine the economic and environmental gains from these GE crops.

I haven’t had a chance to read the book yet but I most certainly will.  I am curious to know how the report defines “sustainability” in relation to GM food crops.  In the meantime, the New York Times has weighed in on some clearly unsustainable aspects of this technology:

Use of Roundup, or its generic equivalent, glyphosate, has skyrocketed to the point that weeds are rapidly becoming resistant to the chemical. That is rendering the technology less useful, requiring farmers to start using additional herbicides, some of them more toxic than glyphosate…Shares of Monsanto [the manufacturer of Roundup], which have been falling since January, slipped nearly 2 percent Tuesday to $67.75.

When the FDA first approved GM food crops for planting in 1994, critics warned that overuse of Roundup would eventually promote the growth and proliferation of plants resistant to this chemical.    Well, yes.

As for the scope of planting, we have Louis Umerlik to thank for creating these nifty maps of use of GM crops in the U.S.  Start with this one (it gives references to sources of the information).  Then look at his maps of soybean, corn, and cotton plantings.  Enjoy (or not).