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Calcium and aluminum impacts on sugar maple physiology in a northern hardwood forest

Forests of northeastern North America have been exposed to anthropogenic acidic inputs for decades, resulting in altered cation relations and disruptions to associated physiological processes in multiple tree species, including sugar maple (Acer saccharum Marsh.). In the current study, the impacts of calcium (Ca) and aluminum (Al) additions on mature sugar maple physiology were evaluated at the Hubbard Brook Experimental Forest (Thornton, NH, USA) to assess remediation (Ca addition) or exacerbation (Al addition) of current acidified conditions. Fine root cation concentrations and membrane integrity, carbon (C) allocation, foliar cation concentrations and antioxidant activity, foliar response to a spring freezing event and reproductive ability (flowering, seed quantity, filled seed and seed germination) were evaluated for dominant sugar maple trees in a replicated plot study.

Publication:
Tree Physiology
Date:
October 8, 2013

Effects of Acidic Deposition and Soil Acidification on Sugar Maple Trees in the Adirondack Mountains, New York

High levels of atmospheric sulfur (S) and nitrogen (N) deposition have substantially damaged ecosystems in the Adirondack Mountains of New York. Efforts to quantify damage have largely focused on aquatic effects2 However, limited recovery of surface water acid?base chemistry in response to large (>40%) decreases in S deposition over the past two to three decades has been attributed to depletion of soil calcium (Ca) and other base cations that may be ongoing despite declining acidic deposition. Availability of soil Ca has also been linked to changes in terrestrial faunal and vegetation communities in Adirondack hardwood forests.

Publication:
Environmental Science & Technology
Date:
October 8, 2013

The “Jones Rule of 86” Revisited

The Jones “Rule of 86” was devised in 1946 by C.H. Jones, a scientist and educator at the University of Vermont. The gist of the rule is that ifone divides 86 by the sugar content of sap, you can estimate the amount of sap required to produce a gallon of syrup.

Publication:
Maple Syrup Digest
Date:
October 1, 2013

Sulfite Concentration in Pure Maple Syrup

Maple syrup is a natural product free of artificial coloring or other additives. Regardless, some publications mention that maple syrup may contain sulfites. In this study, which is conducted by Center ACER in collaboration with UVM Proctor Maple Research Center, direct measurements of sulfites concentration in maple syrup samples collected during 2011 and 2012 were made.

Publication:
Maple Syrup Digest
Date:
October 1, 2013

Age, allocation and availability of nonstructural carbon in mature red maple trees

The allocation of nonstructural carbon (NSC) to growth, metabolism and storage remains poorly understood, but is critical for the prediction of stress tolerance and mortality. We used the radiocarbon (14C) Ôbomb spikeÕ as a tracer of substrate and age of carbon in stemwood NSC, CO2 emitted by stems, tree ring cellulose and stump sprouts regenerated followingharvesting in mature red maple trees. We addressed the following questions: which factors influence the age of stemwood NSC?; to what extent is stored vs new NSC used for metabolism and growth?; and, is older, stored NSC available for use?

Publication:
New Phytologist
Date:
July 14, 2013

Sugar Maple Sap Yields Using One or Two Tapholes Per Tree

Studies currently underway at the University of Vermont Proctor Maple Research Center (PMRC) are examining the effects of accumulating internal taphole damage on the ability to support future tapping, as well as related subjects such as the effects high vacuum sap extraction might have on tree growth, all with the goal of developing new sustainable tapping guidelines. However, along with focusing on the possible negative effects of tapping and sap extraction, it is important to examine how certain practices might lead to greater sap yields.

Publication:
Maple Syrup Digest
Date:
June 1, 2013

2012 Maple Tubing Research

In 2012 a variety of spout and tubing cleaning and replacement options were tested to determine the extent of sap yield changes. These tests were done at the Cornell Arnot Research Forest.

Publication:
Maple Syrup Digest
Date:
February 1, 2013

Chemical Composition of Scale in Maple Syrup Evaporators

The goal of this work was to investigate the chemical composition of the scale that is deposited on maple evaporator surfaces during sap processing. Knowing the chemical composition of scale produced in modern equipment and how it compares to previously published values for loose sugar sand may aid in understanding how best to remove these unwanted deposits.

Publication:
Maple Syrup Digest
Date:
December 1, 2012

Seasonal dynamics and age of stemwood nonstructural carbohydrates in temperate forest trees

Nonstructural carbohydrate reserves support tree metabolism and growth when current photosynthates are insufficient, offering resilience in times of stress. We monitored stemwood nonstructural carbohydrate (starch and sugars) concentrations of the dominant tree species at three sites in the northeastern United States. We estimated the mean age of the starch and sugars in a subset of trees using the radiocarbon (14C) bomb spike. With these data, we then tested different carbon (C) allocation schemes in a process-based model of forest C cycling.

Publication:
New Phytologist
Date:
October 7, 2012

Tubing Cleaning – Methods Used in the U.S.

A wide variety of cleaning techniques are currently used in the maple industry, including rinsing the system with pressurized air and water, or attempts to sanitize with chemical solutions such as peroxide, bleach, or alcohol. However, the effectiveness of these cleaning techniques in reducing microbial populations and increasing annual sap yield is often questionable.

Publication:
Maple Syrup Digest
Date:
October 1, 2012