By Isabell Newlin, Good Food student worker
Elm Street, which runs by the President’s house and the Good Food Garden, is lined with sugar maples. If you have walked down this street in the past few weeks, you might have noticed a couple of blue bags hanging from the trunks. This winter a few of us (Swarthmore students) tapped three of these maples, and we have been boiling the sap down to make syrup.
Equipment used to collection the sap. photo credit: B. Dair
To tap a maple you need a drill (7/16 in), a spout, a mallet, and a bucket. As the days get warmer and temperatures rise above freezing, the difference between day and night generates pressure in the roots of the maples and their sap runs up from the roots into the trunk and branches.
Drill a hole about two inches into the tree and tap the spout into it with your mallet. Angle the drill upwards at a very slight angle so that gravity will draw the sap down into your bucket. At the end of the spout is a hole, to catch the sap is coming upwards from the roots. There is a hook on the spout on which to hang a bucket, or bright blue bag. In the Delaware Valley, the sap often starts running at the beginning of February, when it first gets up to 40 degrees F.
The amount of sap we get each day varies a great deal. When it is warm, more than a gallon; when it is below freezing, very little. Sugar maples, Acer saccharum, have the highest concentration of sugar in their sap, but you can make syrup out of the sap from silver maples, Acer saccharinum, and black maples, Acer nigrum, too.
Blue bags used to collect sap. photo credit: B. Dair
We have collected about 20 gallons of sap over the past two weeks, which as syrup is very roughly 1/30th its original volume.