Sap Discovery Could Turn Syrup-Making Upside Down : The Salt For centuries, people thought sap had to flow down a tree's body through a spigot at the bottom. But researchers have discovered that sap can flow upward, too, which allows syrup production from much younger trees, and could even turn maple syrup into a row crop.
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Sap Discovery Could Turn Syrup-Making Upside Down

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Sap Discovery Could Turn Syrup-Making Upside Down

Sap Discovery Could Turn Syrup-Making Upside Down

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There are some rules in the natural world: rain falls from clouds, trees grow up from the ground and syrup flows out of big, old trees. Well, that last rule turns out not to be so hard and fast. In 2010, researchers from the University of Vermont were testing ways to gather sap from a mature tree when something unusual happened. All the moisture in the tree dried up by the sap was still flowing. Which meant sap didn't flow exclusively top to bottom from really old trees, which is what everyone had thought for centuries. Sap must have been coming up from the ground. And it didn't matter if the tree was old or just a sapling. The researchers published their findings last year and it is starting to ripple through the community of sugar makers.

LAURA SORKIN: It had never occurred to anyone and it's just always been done this way.

MARTIN: This is Laura Sorkin of Vermont. She recently wrote a piece on this in Modern Farmer magazine. The discovery is important, she says, because it means you could create a syrup farm of sorts.

SORKIN: You can densely plant the saplings in a row, and when it comes time for the freeze-thaw cycles, they would lop off the top, cap it off, put vacuum on it and put a tube in and that would basically get your sap as opposed to getting it from a mature tree.

MARTIN: But Sorkin says that takes some of the romance out of maple syrup harvesting.

SORKIN: Aside from harvesting fish from the sea, pretty much everything else that we eat comes from neatly planted, nicely managed row crops grown in fields. Maple syrup, on the other hand, is something that, you know, we head off into the wild forest to get it. Vermonters, I think, would be very reluctant to give that up.

MARTIN: Most of the rest of the food we eat is grown on farms.

SORKIN: There's no reason why it shouldn't be the same for maple syrup. But still, you know, everyone that I mention this to, their reaction is, it's quite visceral. They're just, what? That's wrong.

MARTIN: And is this whole tapping trees thing worth it anyway? I had to ask. Can you just explain to me what it tastes like, really good maple syrup?


SORKIN: I would just have to say ambrosia.

MARTIN: Ambrosia.

SORKIN: It's sweet but it's so much more than that. When combined with things like cream and butter for something like a maple pudding, there's nothing else like it.

MARTIN: Well, now I don't care where it comes from. That's sugar maker Laura Sorkin.


MARTIN: You're listening to NPR News.

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