With sales of nearly $17 billion in 2006, organic food is a major green living trend in the U.S. But the concept of organics is still widely misunderstood.

Trying to buy more organic? There are a few things you should know. In this week's two-part series, we're debunking the Top Ten Organic Myths. Read on for the skinny on some common misconceptions:

1. If it's not certified, it's not organic.

To be labeled organic, food must come from a USDA certified farm. Organic farmers cannot use synthetic fertilizers, most chemical pesticides, bioengineered crops, or sewage sludge. For dairy or meat to be organic, it must be raised on organic feedstock and be free of growth hormones and antibiotics.

But some farmers who adhere to organic principles decide not to seek certification. The process may be too time consuming or they may disagree with USDA's regulations. If you're unsure whether or not a farm is organic, ask about their pest control methods and animal treatment policies.

2. Organic is organic is organic.

One product bears the USDA seal, another says organic on the package, and a third lists organic ingredients in its nutrition label. They're all the same, right?

Not exactly. Only products made with at least 95% certified organic ingredients can bear the USDA seal. If they contain more than 70% organic ingredients, they can make organic claims on the front of their packaging. Products with less than 70%, however, are restricted to listing specific organic ingredients on the side panel.

3. Buying organic is always more expensive.
This isn't always a myth, since organic produce is generally between 10% and 40% more expensive than conventional foods. But many shoppers consider the "hidden costs" of buying conventional produce, which can include environmental damage from pesticide runoff and unwanted exposure to agricultural chemicals. The good news? You can often find good deals on organic food at local farmers markets and through CSAs.

4. Organic food always comes from small farms.
The modern organic movement began with small farms, farmers markets and local food stores. But the rise in demand has catapulted several farms to industrial proportions. Earthbound Farm, for instance, has more than 34,000 acres of organic produce and sells its prepackaged salad mixes in 75% of supermarkets nationwide. Organic has gone big.

Next issue, we'll debunk the rest of our Top Ten Organic Myths! Stay tuned...

To read the USDA's consumer brochure on its organic regulations, click here. Find a farmers market near you at localharvest.org. Download Puget Sound Fresh's guide to local CSAs on their website.