Author: van den Berg, Abby K.

Showing 1 – 10 of 76 resources

Why Does the Sap Stop Running After a Few Days if it Doesn’t Freeze Again?

Without a freeze, the flow of sap will continue to slow and eventually stop because there is no longer a difference between the pressure inside and outside of the tree. However, producers often observe an uptick in sap flow during the daytime over a few days. Why does this occur? Where did the extra sap come from? Typically, these short bursts of increased sap flow happen when the temperature warms over the next few days. The warm temperature causes gas bubbles in the wood fibers to expand and squeeze more water from the wood tissues, where it flows into the vessels and out through the taphole. This might occur for a couple of days, and eventually turn into slow weeping flows before ceasing entirely.

Publication:
Maple Syrup Digest
Date:
March 27, 2023

North American Maple Syrup Producers Manual, 3rd Ed.

Since 1958 the North American Maple Syrup Producers Manual has served as a basic reference source for the production of pure maple products. This 2022 edition provides up-to-date, science-based information and recommendations relating to all aspects of the industry. The guidelines presented will help users ranging from the hobby and beginning producer level to those well-established in the industry. In addition, the information herein will benefit foresters, land managers, Extension and outreach personnel, and others aiming to provide assistance to those in the maple industry. Numerous photographs, tables, a glossary and hyperlinks to selected source materials are included.

This publication is also available in print, at www.mapleresearch.org/ordermanual.

Date:
July 19, 2022

Exudation Pressure in Maple Trees: Comparing Simulations with Experiments

Exudation is the process whereby trees can generate a large positive pressure in stems or roots during months when the tree is leafless and mostly dormant and temperatures fluctuate above and below freezing. This article aims to provide an update on recent modelling efforts
in combination with experimental measurements from red/sugar maple trees at the University of Vermont Proctor Maple Research Center that validate the model results.

Publication:
Maple Syrup Digest
Date:
June 1, 2022

Ask Proctor: Defoamer

We regularly get questions from maple producers about which defoamers are the best to use. Of course, the answer is…it depends.

Publication:
Maple Syrup Digest
Date:
September 1, 2021

Wound Response to Taphole Rejuvenation Practices

In response to injury from wounds such as tapholes, trees initiate processes to compartmentalize the affected area in order to prevent the spread of infection by disease- and decay-causing microorganisms beyond the wound, and to preserve the remaining sap conducting system (Shigo 1984). This results in the formation of a column of visibly stained wood above and below the wound, and the affected zone is rendered permanently nonconductive to water and nonproductive for sap collection. These processes, along with effects from microbial activity, are responsible for the gradual reduction in sap flow from tapholes over the course of the production season. There has been recent renewed interest in strategies which attempt to extend the standard sapflow season or increase overall yields through the “rejuvenation” of tapholes. As part of a multi-year experiment to investigate the yields and net economic outcomes of several taphole longevity strategies, we conducted an experiment to investigate the volume of NCW generated in response to two of these strategies.

Publication:
Maple Syrup Digest
Date:
June 1, 2021

Keys to high maple yield

Comprehensive video on how to make the most of your sugaring season, covering tapping, tubing, and efficient boiling.

Date:
May 26, 2021

Why sap may not always flow well in early season

Maple producers know that when the temperature starts to rise in the spring, sap flows can’t be far behind. But when the weather starts to warm early in the spring and temperatures seem favorable for good sap flows, they are sometimes left wondering why the sap hasn’t started to run. There are several explanations for the disconnect between warm air temperature and a lack of flow during
the early season.

Publication:
Maple News
Date:
May 7, 2021