Every spring, Kemp Station taps maple trees and produces a few gallons of maple syrup. In March 2026, we are planning a public demonstration project—moving beyond the simple sap buckets and sap bags—to a modern tubing system for gravity-flow sap collection. This demonstration is designed for the small maple sap operation and is all about maximizing efficiency with minimal costs.
Before installing the first piece of tubing, careful planning is essential. The system must accommodate the number of tapable trees and, most importantly, the existing topography. We are fortunate to have the right topography at Kemp Station with sugar maples growing in an around a natural bowl in the landscape. This is the perfect setup for a simple tubing system. A non-vacuum, or gravity-flow system, is designed for what is called a “natural vacuum.” This system can develop a natural vacuum as a column of sap fills the lines and slowly moves toward the tank, which in turn increases the overall sap yield. The fundamental principle is that the tubing must be kept tight, straight, and sloping downhill. Any dips or sags can slow the flow and defeat the purpose of the natural vacuum.
The smallest components of our system are the lateral lines, typically 5/16-inch tubing. These lines run from tree to tree, collecting the sap from the tapholes. For a gravity system, the installation needs to encourage the lines to fill with sap and maintain the liquid column. To achieve this:
- We are aiming for 10 to 15 taps per lateral line, and keeping each line around 150 feet or less in length.
- A dropline, 30 inches or longer, is used to connect the taphole to the lateral line. The length helps spread out tapholes over the trunk from year to year.
- Where a natural slope is present, the lateral lines branching off the larger mainlines should run up the slope from the mainline, rather than across it. This arrangement is crucial, as it maximizes the natural vacuum that can be achieved when the 5/16-inch lateral lines become full.
The mainlines are the larger conduits that collect sap from multiple lateral lines and transfer it to the collection tank. They are a more permanent part of the sugarbush infrastructure, ranging from 3/4 inch to 2 inches in diameter.
- The mainline path is dependent on the location and density of tapable trees, and it will often follow the sugarbush's natural surface drainage pattern. It is critical for the mainline to be installed on a fairly constant grade with absolutely no dips or sags.
- Mainlines must be supported by a tight wire strung along the path, which prevents sagging. If you have ever put up a wire cattle fence, similar tools are used to install a tight mainline.
- If the ground is very flat, we gain slope by installing the mainline progressively higher off the ground the further it goes into the woods, up to a practical height of about six feet. Our topography at Kemp Station should work well for this mainline demonstration.
The final piece of the gravity puzzle is the storage tank—the "reservoir" where all the sap ultimately flows.
- The collection tank must be placed at the lowest practical point of the sugarbush to allow all mainlines to flow directly into it via gravity.
- In areas with very little or irregular slope, the sugarbush may be divided into compartments, requiring the use of several remote tanks, each serving a shorter group of mainlines. We will only have one tank at Kemp Station. We will use a small transfer pump and portable tank to bring the collected sap to our boiling operation.
Watch for our program announcements later this spring. This demonstration project will offer hands on examples of sap collection and maple syrup processing—a great lesson in applied science, leveraging gravity to turn tree sap into the first sweet harvest of the year.
