If you're not from the East, you probably haven't given much thought to maple syrup - other than the fake stuff that most of us pour over pancakes. But real maple syrup is receiving lots of attention, tapping into our interest in quality artisan foods.

"It's a very natural product," says Tim Perkins. "Pure maple syrup is simply sap that's been boiled - that's all it is."

Perkins, director of the University of Vermont Proctor Maple Research Center, has seen demand rise. "There are more taps out there now than 10 years ago, because they're selling more syrup, and they can get the price they need to make it."

A look at the favorite pancake topping:

• There's a reason Vermont is the largest producer of maple syrup in the U.S. "This is the only area where you can make maple syrup," Perkins says. While maple trees grow elsewhere, the weather conditions aren't conducive to strong sap flow.

• March is the beginning of the syrup-making season. The ideal time to tap trees occurs when there are warm days followed by sub-zero nights. Because sap is mostly water, if it's too cold for too long, it will ice up in the trees. Warm days are needed for tapping the sap; cold nights give the trees a chance to recharge by pulling water from the soil.

• Maple trees are uniquely suited for tapping because they have "positive stem pressure, like car-tire pressure: Put a hole in it and sap drips out ," Perkins says.

• What comes out of the tree is sap, not syrup. The sap is 2 percent sugar, the rest water, and has to be boiled to make the syrup. It takes 40 gallons of sap on average to get 1 gallon of syrup.

• By federal standards, the final product must be 66 percent sugar (after boiling). Vermont's standards are slightly higher.

• Syrup grades are only a reflection of the color; not quality or flavor. The grades are: Grade A Light Amber, Grade A Medium Amber, Grade A Dark Amber and Grade B. Color depends on the time of season that the syrup is made. Earlier in the year, the syrup is lighter; as the season progresses, it grows darker. Grade B is the darkest color, usually used in baked goods where you want pronounced maple flavor.

"It's really a matter of personal preference and what you're going to use it on," says Perkins.