To wrap up this series let’s examine what would happen if conventional agriculture abandoned the practices discussed last week as called for by the sustainable agriculture movement. How “sustainable” would that be for the environment? First a reminder of what we are defining as sustainable:
1. Any of a number of environmentally friendly farming methods that preserve an ecological balance by avoiding depletion of natural resources.
2. The production of food, fiber, or other plant or animal products using farming techniques that protect the environment, public health, human communities, and animal welfare.
Unfortunately there isn’t room for great detail but the information is readily available.
• The elimination of GMO technology – This would result in a significant increase in the use of insecticides, fungicides and herbicides not nearly as friendly to the environment. Since GMO technology has resulted in better water use efficiency more irrigation would likely result and rain fed crops would experience greater water stress. Heat and cold stress technology would be lost. Crop quality would decrease as would the overall nutritional profile while the shelf life of many crops would decrease. The overall result would be increased pesticide usage and decreased crop yields. More land needed to produce the same yields while agriculture looks to feed two billion more people over the next twenty years.
• Elimination of synthetic fertilizers and pesticides – Eliminating synthetic fertilizers would dramatically decrease yield and currently there is no way to replace the needed amount of nutrients with “organic” fertilizers. Eliminating synthetic pesticides also significantly decreases yield and crop quality. And since a goal of sustainability is to protect the environment, eliminating pesticides would make reducing and/or eliminating tillage much more difficult, result in more tillage for weed and pest control while increasing soil water and wind erosion.
• The use of hormones and pharmaceuticals in livestock production – First keep in mind these technologies aren’t used like candy and strictly regulated. Let’s focus on beef cattle production. The responsible use of implants significantly decrease the cost of gain and therefore the price to the consumer. Implants also mean less feed is needed per pound of gain and results in leaner meat. Overall less land is needed to produce feed for protein production. One article said that eliminating implants would mean more acreage in corn equivalent to the state of New York. The amount of estrogenic activity found in implanted beef while slightly larger than non-implanted is dwarfed by the amount found in tofu or even bread. Hormones are not used in poultry or pork production. The responsible use of pharmaceuticals in meat production maintains animal health, allows a quicker time to finish, and a healthier food supply.  
To wrap this topic up, if we adopted what the sustainable food movement advocates, the goals in the first two bullet items would rapidly move out of reach.