Winter lure of the (micro) logging life

January 3, 2009

Bitter cold and snow-covered trails make my chainsaw trigger-finger itch. The smell of diesel exhaust mingled with pine pitch is the essence of January on our small, certified tree farm. We plan to cut, winch and skid several cords of log-length firewood to our roadside landing before the snow gets too deep for the tractor in February and before mud arrives in March.

Confession: We're just wannabes, weekend wood warriors. Compared to real commercial loggers, we're micro-choppers. We cut an oak here, a few maples or a birch over there. Skid trails fan into the surrounding woods, where we release the best red oak "crop trees" by removing competing poor-quality weed trees to make our firewood. Our goal is to improve growing conditions for high-quality red oak saw timber, to create small openings in the canopy to let light into the understory to regenerate new seedlings and favor advanced young saplings.

As a self-confessed "skidderchaser," I'm fascinated with logging. We live in one of the best wood-growing regions on Earth. And while logging doesn't typically generate much public enthusiasm, if we are not willing to meet our domestic demand for wood here in New Hampshire, we're forfeiting productivity and importing what we consume from someone else's backyard.

After several years of organizing timber-harvest tours sponsored by the Forest Society, I’ve observed that skilled professional loggers and their machinery appear to be a misunderstood and under-appreciated link in the state's wood-supply chain. Beyond the noise, diesel horsepower and complexity of mechanized timber harvesting, logging language requires some translation.

Small-scale, old-fashioned "hand-felling" utilizes chainsaws to fell trees, limb the tops and lop the resultant "slash" low to the ground. Loggers then rig noose-like "choker" chains to assemble a hitch of cut logs that is winched to the heavy, steel-plated arch of a "cable skidder" by winding cable onto a rotating drum. With log ends up off the ground, the rubber-tired, four-wheel-drive skidder, hinged in the middle to turn in tight spaces, pulls logs to a landing or "log deck," where logs are sorted and stacked to await transport.

Large-scale, highly-mechanized timber harvests include whole-tree harvesting equipment such as a "feller-buncher" – which can accomplish more work than a bunch of "fellers."

Mechanized feller-bunchers run on steel tracks like an excavator. Instead of a bucket, they have a mechanical cutting head with hydraulic arms that grasp trees firmly to hold them upright while a high-speed saw blade slices each stem from its stump. Tracked machines then carry several upright trees to an opening along a skid trail, where whole trees are tipped horizontally without damage to the surrounding forest. A "grapple skidder" with long grapple arms then grasps each hitch and drags branches, limbs, twigs and all to the landing.

Observing a well-organized and efficient mechanized logging operation is akin to watching the popular "How It's Made" series on the Discovery Channel. A log landing becomes a temporary forest factory where high quality saw timber and various low-grade wood products are processed by species to feed raw logs to diverse wood markets.

Softwood and hardwood "sawlogs" are sold by species, grade (quality) and length. Softwood -- pine, hemlock and spruce -- are generally sold in 16-foot lengths stacked on a trailer that holds 5,000 board feet. An individual, large, 16-foot cut pine log might contain 150 to 200 board feet, such that each truckload of sawlogs comprises some 25 to 35 logs per truck. More valuable hardwood logs are sold in shorter lengths of 8, 10, or 12 feet. On average, 80 percent of the value of a given tree is contained in its first butt log.

A quality sawlog is perfectly cylindrical. Few trees in the forest qualify.

In small logging operations, logs are "bucked" to assorted lengths using a chainsaw. Logs are sliced to optimize the longest length of straight trunk as is practical while eliminating crotches and minimizing short, low-grade "culls." Larger operations use a crane to place trees on a steel bunk adjacent to a huge saw called a "slasher," which cuts timber to length to await transport to a sawmill. Log trucks access the log landing via a durable, year-round haul road.

Higher on each tree, crooked logs, crotches and top wood with branches or knots is unsuited to be lumber. Low-grade products include pallets and tie logs, fuel-wood chips sold by the ton, softwood pulp used to make newsprint, and hardwood firewood sold by the cord.

"Biomass" wood chips are sold to large chip-burning boilers, which burn low-quality wood chips to produce energy as a renewable alternative to fossil fuels. Crooked tops, limbs and branches that in the past would have been left in the woods or on the landing are fed into a giant chipper that grinds trees into chips and blows them into a "chip van" pulled by tractor trailer to transport up to 40,000 pounds – 20 tons of "green" (still wet) wood chips – to a biomass plant.

Winter is traditionally the season for logging in New Hampshire forests. Frozen ground covered by a slick blanket of snow offers ideal conditions to skid logs down packed trails to a log landing. As bitter cold and snowy weather arrives, I head into the woods to follow the lure of the logging life.