Institution: UVM Proctor Maple Research Center

Showing 51 – 60 of 142 resources

Does Color Matter? Spouts come in variety of hues. Does it affect yield?

In general, it is presumed that any effect of Òspout colorÓ on sap yield arises due to thermal warming of darker-colored spouts during sunny periods. Darker-colored spouts warm faster and the spout temperature can rise considerably above air temperature when hit by the sun compared to lighter-colored spouts. To assess the effect of Òspout colorÓ on sap yield, we conducted a multi-year study at the University of Vermont Proctor Maple Research Center in Underhill, Vermont. Twelve treatment plots were randomly assigned a different spout type, with one mainline and releaser for each plot.

Publication:
Maple News
Date:
June 1, 2018

Tapping Zone Model – Tubing

This model estimates the proportion of clear, conductive wood in the tapping zone of an individual tree each year (for 100 years) based on the values input for tree diameter, tapping depth, spout size, number of taps, and dropline length. This is equivalent to the chances of tapping into conductive wood in this tree each year Ð if 80% of the wood in the tapping zone is conductive, you have an 80% chance of hitting conductive wood when you tap that tree. The model can be used to estimate whether various tapping practices are likely to be sustainable. A more complete description of the model and guidelines for its use can be found in the companion technical report “A Model of the Tapping Zone”, which is available on the UVM-PMRC website (http://www.uvm.edu/~pmrc).

Date:
June 1, 2018

Climate Change & Maple

Dr. Tim Perkins (Director-University of Vermont Proctor Maple Research Center) discusses the intimate relationship between weather and maple sap flow, changing climatic conditions have the potential to affect the maple industry in a variety of ways. This presentation describes research that has been conducted on climate change and maple as well as new ongoing work, and describe some possible effects of changing climate on the future of the industry in the northeast.

Date:
April 11, 2018

Tree Size and Maple Production

There are several important factors that affect the yield of sap from trees during the production season. One relationship that is sometimes overlooked is the one between tree size and yield. In order to develop models of tree size and yield to answer some of these questions, we measured the sap volume and sugar content from approximately fifty individuals along a wide range of sizes during the 2016 and 2017 seasons.

Publication:
New England Society of American Foresters News Quarterly
Date:
April 1, 2018

Identifying Sustainable Practices for Tapping and Sap Collection from Birch Trees: Optimum Timing of Tapping Initiation and the Volume of Nonconductive Wood Associated with Taphole Wounds

Experiments were conducted to determine two pieces of information essential to identify practices necessary to ensure tapping trees for birch sap collection is both sustainable and profitableÑthe selection of the time to initiate tapping birch trees to obtain maximum yields, and the volume of nonconductive wood (NCW) associated with taphole wounds in birch trees. The yields obtained from various timing treatments varied between sapflow seasons, but indicate that using test tapholes to choose the appropriate time to initiate tapping is likely to result in optimum yields from birch trees. The volume of NCW associated with taphole wounds in birch trees was highly variable and generally quite large, averaging 220 times the volume of the taphole drilled, and requiring relatively high radial growth rates to maintain NCW at sustainable levels over the long-term. However, more conservative tapping practices, including reduced taphole depth and increased dropline length, as well as thinning and other stand management practices, can be used to reduce the minimum growth rates required. Producers can use this information to ensure that they use tapping practices that will result in sustainable outcomes and obtain the maximum possible sap yields from their trees.

Publication:
Agricultural Sciences
Date:
March 6, 2018

Hitting the Slope

Analysis of the importance of slope on a variety of tubing systems.

Publication:
Maple News
Date:
March 1, 2018

Ask Proctor

Why are my tapholes leaking and what can I do about it? (Part 2) Being able to recognize what is really a leak and what is not takes some time and thought and experience. This article offers some tips.

Publication:
Maple Syrup Digest
Date:
February 1, 2018

Tree Size Matters

In order to develop models of tree size and yield we measured the sap volume and sugar content from a wide range of tree sizes during the 2016 and 2017 seasons. This article explores the findings.

Publication:
Maple Syrup Digest
Date:
February 1, 2018

Ask Proctor

Why are my tapholes leaking and what can I do about it? (Part 1) There are often several issues involved in leaking tapholes, and sometimes the applied remedy itself turns out to be the actual problem.

Publication:
Maple Syrup Digest
Date:
December 1, 2017

Assessment of the Flavor of Syrup Produced with High-Brix RO Systems

Concentrating sap with reverse osmosis (RO) substantially increases the efficiency and profitability of processing maple sap into syrup by reducing the amount of fuel and time required to complete concentration to syrup density in the evaporator, with gains proportional to the level of sap pre-concentration. Because most flavor development in maple syrup occurs through nonenzymatic browning reactions as sap is processed with heat in the evaporator, it has often been speculated that reduced evaporator processing time resulting from the use of RO might also result in perceptible impacts on syrup flavor. However, a series of controlled experiments conducted at the University of Vermont Proctor Maple Research Center using the same sap processed to different levels with RO determined that concentrating sap up to 21.5% prior to boiling in standard maple evaporators had no substantive effects on syrup composition or flavor.

Publication:
Maple Syrup Digest
Date:
December 1, 2017