Top soil - the stuff that makes farming possible - has depleted by 50% in most of Iowa in the last 100 years. Efforts have slowed the loss, but some loss is always happening. Agriculture, agribusiness if you prefer, is not possible to sustain at the rate we've been doing it. And, even if you can grow it, you still have to transport it to market, and fuel rates have added a lot of cost to the coast-to-coast salad, while a lot of prices are far more expensive in California, my GF is back in Mich, and can't believe the prices they are paying for produce compared with Safeway down the street.
Education - Yes, many grad programs are great, undergrad, particularly at the huge state schools, particularly in the liberal arts are pretty much trashed.