I was at an event last week where Jessica Prentice spoke. In passing she mentioned her Local Foods Wheel, which immediately struck me as brilliant. Since I am not originally from California and don't have a farmer's sense, this tool is very helpful to guide my market visits.
The wheel is currently available in San Francisco and New York varieties (links on the site for where to purchase). The cost is $12.95 plus shipping. I give it a big zealot seal of approval! Go get yours (link on image to visit the site).
For those who haven't yet discovered the importance of seasonality and eating local, it goes something like this:
Since the dawn of agriculture humankind has operated on a schedule of seasonality. We ate food when the earth could produce it, relative to the location where it was produced. It's a simple cycle that we've broken with our greed for convenience. And......local food just tastes better. It's fresher and smaller, which means it wasn't engineered to be bigger and full of water = flavorless.
Purchasing your food out of season means that it must be grown in far off places. The environmental impact of transporting these foods gobbles up unnecessary natural resources. On a planet with a global climate crisis, it is best to try to minimize our impact. Moreover, by eating local you support small farmers and build community relationships, which goes a long way in knowing where your food really comes from. The era of industrialized farming has done a lot to make corporate profits, but very little to support farmers. Plus, pesticides and chemicals are necessary to support the monoculture mentality of the modern agri-business, which does no good for the soil or the people who consume them.
There are many books, blogs and a few movies (including Food Inc - have you seen it??) available to provide more information, if you're interested.