Tubing systems, which had been experimented with since the early part of the century, were perfected and the sap came directly from the tree to the evaporator house. Vacuum pumps were added to the tubing systems. Reverse-osmosis filters were developed to take a portion of water out of the sap before it was boiled. Several producers even obtained surplus desalinization machines from the U.S. Navy and used them to take a portion of water out of the sap prior to boiling. In fact, one is still in use by a producer South-East of Grand Rapids, Michigan.
History is nothing without our learning lessons from it.
Today the technological developments continue. Improvements continue in tubing. Research continues on pest control and improved woodlot management. This has been a very general discussion of maple syrup and maple sugar making. For more detailed information check out the books listed in our reference page.