The picture of the woodpecker is a joke. It is actually a picture of a yellow-bellied sapsucker, which drills rows of holes and then comes back later for the insects stuck in the sap. We have no interest in the bugs, only in the sap, with which we’ll make maple syrup.

Tapping maples is always a big hit with the children, who are always amazed, when I drill a tree, that the sap comes out so swiftly. It truly is under pressure, within the tree, though it doesn’t squirt out. It simply drips out faster than you would think possible, from a block of solid maple.

The kids ask “Why? Why? Why?” and sometimes they corner me, and I have to admit I don’t know. However the simple fact of the matter is that there is more mystery surrounding how sap rises in the spring than most care to admit.

In the summer it is fairly obvious that the evaporation up in the leaves can create a partial vacuum, which helps draw the sap up, but how can the sap be drawn up when there are no leaves?

There are various ideas about how thawing increases the pressure, and freezing decreases it, (creating a slow pulse, if not a pumping heart), however there are no valves, so you would think the flow would go aimlessly back and forth, without direction. In fact some even argue the sap doesn’t even rise, but instead moves in to the heartwood and then back out again.

The children have no interest in such complex thought, and are perfectly satisfied when I simply state the sap rises. Some don’t care much about that, and are only interested in pancakes and waffles. They seem perplexed when I tell them we can’t have syrup five minutes after the drops start plinking and plunking on the metal bucket’s bottom. So perhaps the lesson is actually about patience.

Knowing how impatient they are, I’ll let them drink the sap tomorrow. It is basically water with only the faintest flavor of maple. 95% of the water has to be boiled away to make syrup, which is a steamy later step the children enjoy. However I like to watch their eyes as they drink Dixie cups of the icy cold sap, straight from the pail, fresh from the tree.



    • Glad you liked it. I have to get away from the politics of Global Warming at times, to stay sane.

      WUWT is a life-saver of a site. Thanks for moderating there.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s