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Could the sugar maples have broken bud during unusually warm January temperatures?

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 (

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.

Relationship between Tree Value, Diameter, and Age in High-Quality Sugar Maple (Acer saccharum) on the Menominee Reservation, Wisconsin

Guidelines for managing sugar maple-dominated forests by the single-tree selection method are well established and widely adopted. The forests of the Menominee Tribe in Wisconsin provide an opportunity to validate current guidelines by testing tree value and size/age relationships in forests that have substantially older and larger high-quality trees than can be found through the northern region. We harvested grade 1 sugar maple trees across a wide spectrum of ages and diameters, which we then manufactured into veneer, sawlogs, cants, and hardwood/pulpwood bolts to determine tree value.

Assessing the Commercial Potential of a Site for Maple Sap Collection

These 9 variables are intended to help a potential commercial maple producer evaluate the relative merits of one or more selected woods for profitable maple production. A poor or medium rating does not mean that the woods should not be tapped but that production costs in money or labor will likely be higher or greater investments will be necessary to allow the sap collection to be established relative to other sites. Some problems may be avoided if the potential producer is a creative problem solver. Small-scale producers and hobby producers have less emphasis on financial return, so these variables are relevant but perhaps not weighted as heavily.

Investigating Decreasing Growth Rates of Sugar Maple in the Adirondacks

Relatively little work has been conducted investigating trends and influences of the annual growth of sugar maple trees, utilizing the widths of tree rings to estimate growth rates for each year. Using this tree-ring approach, recent research suggests that growth rates have been decreasing in the Adirondack Mountains of New York State.

The Forests of Southern New England, 2012

This report summarizes the U.S. Forest Service, Forest Inventory and Analysis (FIA) forest inventory data, collected from 2008 to 2012, for Southern New England, defined as Connecticut, Massachusetts, and Rhode Island. In addition to providing regional and state-level summaries, the reports highlights three focus plots, one average or prototypical plot from each State, as a means to better tell the story of the forests of the region. Forests cover an estimated 5,128,000 acres or 59 percent of Southern New EnglandÑ1,736,000 acres in Connecticut (56 percent of the State), 3,028,000 acres in Massachusetts (61 percent), and 364,000 acres in Rhode Island (55 percent). There was no substantial change in the area of forest land between the current, 2012, and the previous, 2007, FIA inventories.

New York Forests 2012

This report summarizes the second annual inventory of New YorkÕs forests, conducted in 2008-2012. New YorkÕs forests cover 19.0 million acres; 15.9 million acres are classified as timberland and 3.1 million acres as reserved and other forest land. Forest land is dominated by the maple/beech/birch forest-type group that occupies more than half of the forest land. The sound wood volume on timberland has been rising and is currently 37.4 billion cubic feet, enough to produce saw logs equivalent to 93.7 billion board feet.

Forests of Vermont and New Hampshire 2012

The first full remeasurement of the annual inventory of the forests of Vermont and New Hampshire was completed in 2012 and covers nearly 9.5 million acres of forest land, with an average volume of nearly 2,300 cubic feet per acre. The data in this report are based on visits to 1,100 plots located across Vermont and 1,091 plots located across New Hampshire. Forest land is dominated by the maple/beech/birch forest-type group, which occupies 60 percent of total forest land area.