You might notice log truck traffic around the Grafton County Complex this fall. A timber harvest will take place under the supervision of the Grafton County Extension Forester, as part of a written forest management plan that has guided the stewardship of the forest over the last 15 years. (The plan will be updated again in 2030.) The Grafton County Forest has been managed by the County Extension Forester since the 1980s.
Trees were marked by the forester and the harvest was put out to bid. The sale was awarded to a contractor from Littleton. All timber harvesting regulations and best management practices will be followed on this harvest.
The harvest will take place on the eastern side of the property, around the fields at the end of the road, and is part of a planned silvicultural treatment. Silviculture is the art and science of establishing, tending, and regenerating forest stands. A stand is an area of forest with similar tree species composition and age class distribution. The harvest will take place in two stands.
One stand is made up of mostly hardwoods and white pine. Hardwoods in the stand include oak, maple, birch, aspen, and cherry. The oak is of good quality, suitable for lumber products. Some of the other hardwoods are of good quality, but many of them are poor quality or low vigor. Many of the white pines have low vigor also. The trees are overstocked, resulting in slow growing, stressed trees.
Forest management decisions depend on landowner objectives and what the land is capable of growing. One objective of the county forest is to grow valuable timber products for periodic income. The most valuable tree species that the county forest’s soils are capable of growing are red oak and white pine.
Oak and pine need a mix of sun and shade to germinate and become established. To regenerate these species, we need to open the canopy to allow adequate sunlight to reach the ground. We don’t, however, want to open it up completely because we need some mature trees to provide seed and light shade. Oak seedlings need to become established in the understory before the canopy is completely removed. The established seedlings are known as advanced regeneration.
White pine can become established in an opening such as a patch clearcut, but it’s better to establish white pine under some light shade due to the white pine weevil. Weevil larvae feed on the terminal leader (the upper most upright stem) of white pines, which kills the leader but not the tree. A side branch takes over and becomes the leader. This creates a crook in the stem, deforming future logs. When growing pine for timber, we grow them under some shade (which the weevils don’t like) until they’re at least sixteen feet tall. This way at least one straight sixteen-foot log develops before weevil damage occurs.
The silvicultural treatment for the hardwood-pine stand is a shelterwood cut. Much of the poor quality and low vigor hardwood will be cut for pulpwood and firewood. Most of the red oak will be retained for seed and shade and to grow larger and more valuable, though some will be thinned to create more space for remaining oaks. The oaks will also continue to produce acorns for wildlife. In addition to acorns, oaks also support a huge diversity of caterpillars which in turn feed a great variety of songbirds as they get ready for their fall migrations to Central and South America.
Some white pine will be retained for seed, though the huge pine seed year we had last year should provide more than enough for regeneration.
Most of the white birch in the stand is of low quality or low vigor. Some will be left standing to provide seed and diversity.
With the imminent threat of emerald ash borer, much of the white ash will be harvested, though some will be retained to provide seed and maintain ash on the landscape.
The second stand is white pine-hemlock with scattered oak and other hardwoods. This stand had some harvesting activity approximately 25 years ago. It was a single-tree and group selection harvest which is just as the name implies – trees were harvested individually and in small groups. The idea is to develop a stand with multiple age classes over time, regenerating small openings and thinning other areas to improve the health and growth rate of residual trees. The upcoming harvest will continue that process.
In addition to trees, the harvested openings will regenerate with shrubs and herbaceous plants. Follow-up monitoring and control efforts will be necessary to keep any invasive plants in check.
Wildlife will benefit from the harvest as the forest responds to the silvicultural treatments. The shelterwood cut will provide a dense understory for food and cover, and the remaining mature oaks and other trees will provide acorns and other seeds for food. Retained live and dead standing trees with cavities will provide nesting and denning sites. The selection cut area will continue to develop layered structure in the stand, which will benefit many species of songbirds.
Products from this harvest will include sawlogs for lumber, railroad ties, and pallets, pulpwood for paper, and firewood. Some of the wood will be sold to mills in New Hampshire and some will go out of state.
The harvest will generate economic activity by providing local, renewable raw materials for sawmills and other wood-using businesses. It will also provide income and revenue for loggers, truckers, sawmills, pulp mills, and for the county government. That’s the beauty of forest management – it can improve wildlife habitat and perpetuate the forest all while generating economic benefits.
