Industrial food production is not very fashionable right now.

Three books by Michael Pollan criticizing the system of giant corporate farms and food factories have topped the best-seller lists. A graphic documentary, “Food, Inc.,” based in part on his books, has been nominated for an Academy Award.

In Washington, Michelle Obama grew vegetables on the White House lawn as an example of self-sufficiency. And across America, more farmers’ markets and restaurants have popped up that sell vegetables and meat produced on small farms.

Diners now scan the menus at their local restaurants for provenances like “Cattail Creek Ranch lamb” or “Hudson Valley rabbit.” And home cooks now await boxes of fresh produce delivered weekly from local growers.

Some of these so-called locavores may think they are part of a national movement that will replace corporate food factories with small family farms. But as much of the East Coast lies blanketed beneath a foot or more of snow, it’s as good a time as any to raise a few questions about the trend’s viability.

First, how practical is local food sourcing in a nation that enjoys a diversity of food? From a practical standpoint, there isn’t much that can be grown in winter in most parts of the country.