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Understanding the relationship between tree size and yield

Timothy Perkins, Mark Isselhardt, Abby van den Berg | UVM Proctor Maple Research Center and UVM Maple Extension, University of Vermont Underhill Ctr., Vermont | Feb. 5, 2018

There are several important factors that affect the yield of sap from trees during the production season.

These generally fall into four categories: tree characteristics, tapping, vacuum, and spout/tubing sanitation.

On tubing, it is sometimes difficult to observe the impacts each of these has on sap yield, by doing controlled research studies it is possible to discern the relationships among certain characteristics and practices.

In fact, some of the common sayings in the maple industry such as “strive for five, no more than ten” and “5% more sap for each 1” Hg vacuum” come directly from such research.

One relationship that is sometimes overlooked is the one between tree size and yield. [ MORE ]

A snapshot of sugarbush lease rates in Vermont

Mark L. Isselhardt, Maple Specialist | Oct. 6, 2017

Many sugar makers in Vermont own the land on which their trees grow. The land may have been passed down through several generations of family ownership or recently purchased on the open market. Sometimes however, producers will pay landowners for the right to tap trees. Whatever the reason, sugar makers and landowners who decide to enter into an agreement, at a minimum, they must agree on a price and terms before tapping can begin. This is just the beginning however as both landowner and producer need to consider several things before an agreement can be reached. Determining length of lease, minimum tree diameter to be tapped, when payment is made as well as determining what restrictions related other activities (thinning, retubing, road maintenance, etc.) needs to be done before an agreement can be finalized. These and other details should be carefully considered and written into a signed lease agreement. This article will focus on just one part of establishing a lease agreement; a snapshot of the current $/tap for lease agreements statewide. [ MORE ]

Are you watching your profits evaporate?

Mark Cannella | May 2017

Maple sugaring in 2015 was not as profitable as 2014. The record crop in 2016 was able to stabilize overall financial performance but on a pound for pound basis the 2016 profit margins were still down as market prices slipped. [ MORE ]

Off-flavor syrup reference available

Mark L. Isselhardt, Maple Specialist University of Vermont Extension Proctor Maple Research Center | February 2017

A new product to help producers identify off-flavors in maple syrup is available for the 2017 production season.

The product, officially known as the Off-flavor syrup reference set, was developed by the University of Vermont Extension Maple Program. The kits are intended for anyone who works with pure maple syrup, especially those who are responsible for grading pure syrup and are using flavor terminology common to U.S. producers. [ MORE ]

Long-term average a better predictor of air temperature

Tim Perkins, University of Vermont Proctor Maple Research Center | Jan. 2017

Whether it is choosing when to tap, or anticipating when the sap will run (or stop), maple production is intimately tied to the daily change in weather. Producers keep a close eye on their trees, and often an even closer eye on the weather forecast.

Although the weather prediction can provide some level of information about the possibility of impending sap runs, it can sometimes lead to a bit of angst if the forecasted weather appears that it will be too cold or too warm for good flows. [ MORE ]

Devastating caterpillar

By Mark Isselhardt, UVM Extension, Maple Specialist | September 2016

An infestation of forest tent caterpillar or FTC (Malacosoma disstria) has developed in several parts of Vermont this summer. This early-season defoliator is a native insect and has the potential to defoliate large areas of hardwood forest. Sugar maple is one of the caterpillars preferred host trees. [ MORE ]

Some confusion over IPA usage

Various Contributors | March 2016

Increased attention to spout and tubing sanitization has led to rising sap yields for maple producers. Cleaning and replacement (use of new spouts, use of Check-valve spouts or adapters, or replacing spouts and droplines) strategies have different effects on sap yields, and each carry their own costs in terms of supplies and labor to implement the various approaches, and thus each has a different net profit. [ MORE ]

Recent trends in the maple industry III - changes in sap yield

Timothy D. Perkins, M.L. Isselhardt and A.K. van den Berg |

This series of articles has described the changes in the U.S. maple industry over the past 15-20 years. We have witnessed an era of tremendous growth in production, much of it coming about due to the addition of taps. Utilizing the data collected by the U.S.D.A. National Agricultural Statistics Service, it is easy to see that one of the more striking changes though has been the increases in the quantity of sap per tap (sap yield) that producers are now able to collect. [ MORE ]