maple producers collect sap?
years, maple producers hung buckets on trees, and allowed the sap
to drip into the buckets. Collecting the sap from hundreds, or even
thousands, of buckets and transporting it to the sugar house was very
hard work. In the 1950s, maple producers experimented with a
new way of collecting sap. They attached a plastic tube to each tree,
which then led to a central collection container or tank (you can
see the tubes in this photograph).
the 1960s, producers and scientists asked whether creating suction
(or vacuum) on the tubes might allow them to collect more sap without
harming the tree. They found that applying suction at the rate of
10 inches of Hg (Hg stands for mercury, a way of measuring the amount
of vacuum) caused a 50% increase in the amount of sap per tap. Applying
15 in. Hg nearly doubled the production per tap. At 20 in. Hg, there
was no further advantage over 15 in. Hg.
have been tapped for over 25 years using vacuum tubing with no apparent
damage to the tree. For more information visit the virtual
tour on sap collection.