Organic vs Local? Who Cares. Neither is Sustainable.
Where the Rubber Hits the Road in Farming
One farmer, in trying to eliminate erosion on his fields uses no-till growing, meaning that older, dead plants are left where they fall and new seeds and crops are planted right over top of them. This means A) the field looks like a big mess compared with his neighbors and B) that weeds are allowed to grow too. To keep them down, the farmer applies a small amount of herbicide, which now means his food isn't organic and he can't sell his vegetables at the premium price. The word shunned comes to mind.
Looking at the carbon footprint of food vs where it's produced vs how many resources it uses still doesn't get to the issue of whether the system is sustainable or not. When it comes to a farming method that is sustainable, you still must factor in costs vs profits which gets us back to massive, farms that get the most they can out of the harvest and worry about next year, well, next year. Looking at local vs organic boils the system down into something it's not: "we've come to see sustainability as some kind of fixed prescription - if you just do these 10 things, you will be sustainable and you won't need to worry about it anymore."
Growing Organic En Masse
While organic farms uphold to stricter standards, they are still trying to keep up with their conventional rivals in terms of production and that amounts to cutting costs somehow. The organic standards encourage farmers to replenish soils on site, via manure or crop rotations or no-till, from the example above. This is costly and to cut costs, some farmers just truck in manure from feed lots. Trucking in manure (emissions) from feed lots (hormones, and other food safety issues) begs the question - is this organic item still the holy grail of food? Plus, its very hard to keep GMO tainted seeds and food out of organic fields, meaning most of the items we call organic today are just "mostly" organic.
Before you completely write the article off, there are examples of sustainable, organic farms, but they are few and far between, and they take way more work than a traditional farm (meaning they cost more to run). If we were to convert all of the US industrial farms to organic, consider the resources we would need. According to the article, current organic farms are able to replenish their soils with manure, etc because they only represent 3% of the food supply. Ramp this up to feed the 6.7 billion people (and growing) currently on the planet and we've got a problem. If we want to get rid of fertilizers and use cover crops and other alternative farming methods, we would need 2-3 times the amount of farmland currently available - which means knocking down more rainforests and taking over more land for farms.