Years of planning paying off on forest management practices at Blackwater Dam

Courtesy Photo | Freshly cut trees are loaded onto a vehicle to be sold.  

WEBSTER, NEW HAMPSHIRE, UNITED STATES

11.09.2018

Courtesy Story

U.S. Army Corps of Engineers, New England District

by Joshua Levesque
Edward MacDowell Lake
Earlier this year, the Blackwater Dam team and their partner, the New Hampshire Division of Forest and Lands, successfully completed a cut-to-length harvesting operation to implement a partial overstory (tree top) removal in order to regenerate White Pine trees at the Dam. This operation was the culmination of a 20+year undertaking to establish a White Pine generation project on Corps lands.
The Corps of Engineers has had a license with the state of New Hampshire’s Department of Natural and Cultural Resources for Wildlife and Forestry Management since 1989. Early in the 2000’s a small 27- acre plot at the Blackwater project caught the attention of the State Forester for its potential regenerative qualities for white pine. The tree, which is used in every aspect of the building and timber industry in the Northeast, has huge economic value both in terms of dollars and social economic importance. The trees offer wildlife value to a large diversity of species.
The State Forester proposed a small experimental shelterwood harvest that would incorporate three different stocking levels to determine how overstory stand density influences white pine regeneration. A shelterwood harvest is used to leave seed-producing trees uniformly throughout a section of the forest, also known as a stand. The ultimate focus was on managing for white pine, with a component of hemlock, red spruce and balsam fir, and to establish young successional growth for biodiversity. The state of New Hampshire is responsible for the proper management and execution of the long-term program and developed a 25-year working forest management plan for each of the District’s projects in the Merrimack River Basin.
In the winter of 2007 a decision was made to equally divide the timber harvest area into three, 9-acre stands. Within these three separate stands, tree density was reduced to 10 trees per acre in one stand, 30 trees per acre in another and 90 trees per acre in the last stand. In each case efforts were made to preserve a few of the most robust and healthiest pines, known as “seed tree cutting” –trees that are selected for their genetics and are intentionally left as a future seed source.
After a 10-year regeneration survey conducted by the State Forester James Airey, the results were clear -- the site conditions demonstrated exceptional regenerate qualities, but more importantly, the 10 tree per acre application clearly had the best results. The pine seedlings that began in 2007 were now nearly 20 feet tall in some cases and showing growths of 2-3 feet per year. Compared to the other two sites, the same aged pine were averaging less than half that height. This regeneration survey helped determine the next steps needed for future sustainable forest management in this area.
In 2018 a proposal was agreed to between the state and the Blackwater team to plan for a partial overstory cut. The management approach was to reduce stand density to 10 trees per acre within the two other stands in order to further encourage the white pine to regenerate. Within the stand initially cut to 10 trees per acre, the entire overstory was recommended to be removed to fully release the established, advanced white pine regeneration. The residual mature white pine trees left would provide some shade protection to seedlings in order to prevent damage by white pine weevil. These trees would also serve as a seed source for the recruitment of additional white pine seedlings.
A Cut-To-Length (CTL) harvesting operation was used in 2019 by the logging contractor for this overstory harvest. This cut operation allowed for the low-impact removal of timber. The equipment consisted of a Harvester that cuts the tree, de-limbs the stem, and then cuts the stem to length all directly at the stump. Additionally, delimbing occurs in front of the harvester, so the limbs and slash can be used as a mat upon which the machine travels. The CTL is also able to fell or place trees directionally resulting in considerably less damage to the white pine regeneration compared to the amount of stand damage and soil disturbance conventional harvesting does.
This timber harvest will create young forest habitat for many species of wildlife and build tree species diversity. Within the next several years, another regeneration survey will help determine the results of this timber harvest and the next steps. No Corps of Engineers dollars are used directly in the management of the lands, but rather income from the harvested timber is allocated as a resource that the state can use to resource the staff and equipment necessary to manager the program. Income from the timber can also be used for future projects, habitat improvements and towards providing sustainable Silviculture. All of the revenue generated at the project returns to the project.
The state of New Hampshire through their Department of Natural and Cultural Resources, and the State Forester James Airey, manages the majority of the lands at Hopkinton-Everett, Franklin and Blackwater for wildlife and forest management through the license agreement. Our partnership has developed a beneficial approach focused on maintaining a sustainable forest management program for conservation and other benefits as well as to provide for the greatest diversity of species indigenous to the surrounding area.

• Date Taken: 11.09.2018
• Date Posted: 06.21.2019 09:33
• Story ID: 328621
• Location: WEBSTER, NEW HAMPSHIRE, US