My conventional grocer ships the kale to Wisconsin from Georgia, and by the time it gets here it is yellow and wilted. Compared to the farmers market, where the kale I find is dark green and crisp. Same story for most other produce. The winters drive me crazy, because kale grows great in January in Wisconsin, yet the grocers insist on shipping it from Georgia, so I go without.

Efficiency compared to what? Stripping of minerals? Loss of topsoil? Petroleum dependence? Water contamination? Yeah, it's true, conventional farming is more efficient at all those.

You're concerned about needing more farm land with "organic" practices, but in truth, "conventional" farming is destroying arable land at an alarming rate.

Edit: http://en.wikipedia.org/wiki/Livestock%27s_Long_Shadow

http://ngm.nationalgeographic.com/print/2008/09/soil/mann-te...