Resource type: Research

Showing 1 – 10 of 380 resources

How controlled inoculation of sap tubing with Pseudomonadota strains may influence maple syrup quality

The study recently published in Canadian Journal of Microbiology and available in open access consisted in the inoculation of the sap collection system with three Pseudomonadota strains and to assess the microbial and organoleptic quality of maple sap and syrup (Gagnon et al., 2025). This work represents a significant step: rather than simply characterizing microbial communities, the study tested whether an intentional inoculation of selected bacterial strains into tubing systems can steer microbial succession and influence syrup quality.

Publication:
Maple Syrup Digest
Date:
December 15, 2025

When to Add a Second Tap Under Vacuum? – Part 1

Determining the proper diameter at which to put a second tap in a maple tree can be difficult. The decision can be affected by numerous factors, including: tree diameter, tree growth rate,  previous tapping history, whether vacuum is used and if so, what level, the additional yield of sap, and the cost/benefit ratio (factoring in both time and $), among others. These considerations have factored into the development and use of tapping guidelines. In some cases, guidelines were developed with science-based answers to some of these questions. In other cases, guidelines were more of a “rule-of-thumb”used by producers in broad regions. While tapping guidelines are mostly, as the name implies, non-regulatory suggestions, in other cases such as in organic production or when producers lease taps, neglecting to adhere to guidelines can have undesirable consequences such as revoked organic certification or losing the ability to access leased taps

Publication:
Maple Syrup Digest
Date:
June 15, 2025

When to Add a Second Tap Under Vacuum? – Part 2

In a previous article we reviewed previous work and described an approach to determine the amount of syrup gained by adding a second taphole to a tree (Perkins et. al. 2025). This study follows up on that work by determining yields from trees across a wide range of sizes with either a single, or two tapholes, over several seasons.

Publication:
Maple Syrup Digest
Date:
June 15, 2025

Reducing Maple Sap Spoilage

Sap spoilage can be minimized by both maintaining optimal storage conditions, particularly at low temperatures and proper sanitation of collection and storage materials. Temperature control is essential in reducing spoilage.

Publication:
Maple Syrup Digest
Date:
March 15, 2025

Variation in Sap Sugar Content Across States

There is little information about how sap sugar varies across the maple producing region.

In most cases, absolute changes in SSR from one year to the next averaged 6.3%, but occasionally changes in SSR of up +20% (ME from 2013 to 2014) and -13% (NH from 2014 to 2015) were found. Some states (MA, NY, MI) exhibited relatively stable or minor changes in SSR across the three years.

In examining these results, northern states appeared to have slightly lower SSR (sweeter sap), while more southern states tended to have lighter SSC (less sweet sap).

Publication:
Maple Syrup Digest
Date:
March 15, 2025

Tapping Below the Lateral Line for a Sustainable Use of Maple Resource

In recent years, someproducers have seen the benefit of tapping maples below the lateral line for multiple reasons. The main reason is to access a larger area of healthy wood on the trunk. This is because the maple tree produces a compartmentalization zone inside the trunk following tapping, which isolates the wound left by the tap hole.

By opting for a tapping pattern that respects the necessary spacing of taps from year to year based on their size and number, the likelihood of tapping into compartmentalized wood is minimized. If, in addition, the tapping area is expanded by allowing tapping below the lateral line, the exploitation of the trunk surface is further optimized, ensuring the sustainability of sap collection.

Publication:
Maple Syrup Digest
Date:
March 15, 2025

Drivers of Sap Flow in Maple

Sap now in maple trees has been described many times. Milburn and O’Malley (1984) provided the first well-accepted modern description,which was later modified and improved by Tyree (1984), then further by Cirelliet al. (2008). Stem pressure and now in maple were then mathematically modelled in detail by Graf et al. (2015) with additional refinements and comparison with field-derived measurements by Zarrinderakhta et al. (2024). While these articles provide extensive detail into the anatomy and physiology of the science of the sap now mechanism, they are somewhat unavailable to most people. A good general description of the sap now mechanism is described in more modest detail in the Third Edition of North American Maple Syrup Producers Manual (Perkins et al. 2022), so won’t be discussed at length here. Rather, this article is aimed at describing pressure gradients and the sources and magnitude of those pressures as they related to sap exudation from maple tapholes.

Publication:
Maple Syrup Digest
Date:
December 15, 2024

A Promising Alternative to Defoamers for Maple Production

Foam development in the evaporator is a phenomenon often encountered in maple production (Martin, 2011). As it passes through the evaporator, the boiling sap can begin to foam quickly, especially at a later stage of the production season. When excessive foaming occurs, the use of a foam control agent, commonly called “antifoaming agent” or “defoamer” in the maple syrup industry, sometimes becomes necessary to avoid problematic overnows (low productivity, loss of product, cleaning challenges, safety, etc.).

Publication:
Maple Syrup Digest
Date:
December 15, 2024

Effects of the January 1998 Ice Storm on Stem and Root Carbohydrate Reserves, Radial Growth and Tree Vigor in Two Vermont Sugarbushes

The ice storm of January 1998 damaged well over 17 million acres of forest in the northeast, including nearly 1 million acres of forests in Vermont (Figure 1, Miller-Weeks and Eagar 1999, Vermont Department of Forests, Parks & Recreation 2000). Many of the areas which experienced damage were active sugarbushes, with severe damage to tubing systems in affected zones.

Publication:
Maple Syrup Digest
Date:
June 15, 2024