What is low-impact logging?

This article was published in the "West Virginia Farm Bureau News, WVU Update" in 2002.

Steven J. Milauskas
Forest Operations Specialist
WVU Appalachian Hardwood Center

    More than 260,000 individuals own part of West Virginia’s 12 million acres of forests. Tract sizes average around 40 acres. Many large forest products companies own large tracts, and the publicly owned Monongahela National Forest consists of more than 900,000 acres.

   Managing and harvesting the forest with gentle or low-impact methods can have different meanings to different types of landowners. For the purposes of this article, I will use the terms “low-impact” and “gentle logging” as if they mean the same thing. Despite somewhat different definitions among people, most landowners usually share such objectives as minimizing damage to the residual stand (the trees that are left after logging).

    Smaller woodlot owners across the country have taken a keen interest in these low-impact logging methods for several reasons. Many newer landowners from more urban areas have a different set of management objectives than traditional farm or woodlot owners. They are often concerned with management for wildlife, recreation, and aesthetics, along with timber management. Traditional farm woodlot owners bring another set of interests to the table. They have increasingly expressed interest in forestry operations that are sustainable, produce income, and support local community interests. Low-impact logging methods are increasingly looked at as a way to help meet these changing landowner objectives.

   Low-impact has different meanings to different individuals, landowners, and organizations. For some, low-impact means logging with horses; others look to using high-tech machines that leave lighter “footprints” on the land. We can have traditional or conventional logging systems that are low-impact or alternative, truly unconventional systems that minimize impacts and incorporate some social or community values. Some of the newer concepts for making smaller woodlot management and logging sustainable and profitable can be exciting. Education and commitment by individuals will be very important if any of these methods are to succeed. This article describes some of the commonalities, definitions, and advantages of low-impact systems.

 What is gentle or low-impact logging?

   Generally, gentle logging systems incorporate several practices that most foresters, landowners, and conscientious loggers could agree on regardless of the type of equipment used:

* having a written forest management or stewardship plan
* planning roads and trails before the harvest
* employing directional tree felling
* cutting stumps low to the ground
* constructing roads and trails to minimum widths
* constructing landings to minimum size and spacing
* minimizing ground disturbance
* paying attention to aesthetics or how the site looks after harvest
* minimizing residual stand damage
* following best management practices (BMPs) as given in the West Virginia Logging Sediment Control Act
* having a good understanding among landowner, logger, and forester of how the site will be harvested, what will be removed, how it will be removed, and measures taken to protect and enhance the remaining stand of trees

    Gentle or low-impact forestry and logging also imply other meanings and objectives to some landowners, foresters, and loggers. It begins with how sustainable forestry is defined. Meeting current needs without compromising the ability of future generations to meet their needs is a common definition of a sustainable practice. Some view sustainable forestry on woodlots as the ability to produce a steady flow of timber harvests and income from their land. Timber stand volume and quality are to be enhanced over time. This typically means many smaller periodic harvests rather than one or two large cuts in a lifetime.

    Such a strategy takes discipline since potential current income may be sacrificed for greater future returns. Low-impact logging here means removing the worst trees first to improve the forest for the future. Since many of the best, high value trees are left to grow, reducing or eliminating damage to the remaining trees is absolutely critical. Trees skinned or damaged by machines, skidded logs, or poor felling can significantly reduce the future value of the stand. Logging costs could be higher when strict constraints on residual stand and site damage are written into a contract.

 A holistic approach

    Many see low-impact logging as part of a holistic approach to forestry. With this approach, low-impact logging should contribute to sustaining forests and local community values, favor local labor and markets, and fit with value-added processes. Practices promoted as making smaller woodlots more profitable to the owner by adding value over time are:

* removing inferior and undesirable trees to improve the value of the timber stand
* logging your own timber using smaller equipment such as a farm tractor
* hiring a proven, committed  low-impact logger that either horse logs or uses smaller, less obtrusive equipment, ensuring minimal stand and site damage and adding value to the future stand
* processing logs into lumber with portable sawmills on site
* drying lumber in smaller solar kilns
* processing into secondary products such as flooring, cabinets, or novelties

    The idea is to add value and increase landowner returns by avoiding middlemen, maximizing on-site processing, and retailing direct to consumers. Implementing such practices requires a large commitment of time and personal energy. In some parts of the country, landowners have joined together in forestry cooperatives.

    Landowner-run cooperatives can provide services and market forest products that give individual smaller landowners an opportunity to maximize the value of their timber. By providing the added monetary values to the timber, specific gentle, low-impact, sustainable forestry methods preferred by members become more affordable, practical, and profitable. The landowner organization might own a portable sawmill or contract with the owner of a mill to do custom cutting. The forest could be managed and harvested across boundaries to ensure that smaller woodlots can be economically and sustainably logged. These larger, cooperatively managed areas may be necessary in order to promote stable relationships with loggers dedicated to using certain low-impact methods.

    Gentle or low-impact logging can exert a positive influence over the landowner’s forest and local community. The range of low-impact logging definitions is wide, but most landowners agree on the specific “core” practices previously mentioned. Several systems are used to implement these practices. As important as these harvesting systems are, the logger’s attitude and dedication are just as critical in carrying out these gentle methods. Ultimately, the effectiveness of the logging operation in carrying out the prescription or plan is one of the most important factors in achieving the landowner’s objectives for his sustainable forest.

Low-impact logging systems gaining popularity

   Four basic types of harvesting or logging systems are used in low-impact logging. These systems differ from one another but have many of the same objectives.

 Horse logging

    Horse logging is the method of choice for many with environmental leanings. Sometimes, horses are used to skid the trees to main or permanent roads where machine skidders or forwarders take over. Proponents of horse logging point out that horses cause less soil compaction and ruts than heavy machinery, that skidding log lengths rather than tree lengths allows tighter turns with less residual stand damage, and that the operation is quiet. A specially designed arch on wheels can be used to raise the front of the log up off the ground during skidding. This prevents the front of the log from digging into the ground when it is pulled.  

   Horse logging is not a high-production system. Horses can skid several thousand board feet of logs per day depending on terrain, slope, log size, skidding distance, etc. Depending on conditions, this might be 15 to 30 logs 24 feet long and 20 inches in diameter. Several horse loggers work regularly in West Virginia.

 Small farm-type machine systems  

    Small woodlot farmers use farm tractors with specialized attachments such as grapples, winches, blades, and log forks to harvest and process their own timber. Woodlot owners and workers should be trained in safety and be aware of the hazards of logging. West Virginia has several fatalities and many serious accidents each year from logging activities. Contact the W.Va. Division of Forestry or the W.Va. Forestry Association if you need a schedule of logging safety classes. Consider contracting with a professional feller if you have many trees to harvest.

   A wide assortment of machines and equipment have been designed or modified for the small-scale woodlot logger. Felling by chainsaw is common. Skidding can be done with several techniques. The most common method is a four-wheel drive farm tractor with a winch or grapple. The tractor should have rollover protection. Remote radio-controlled winching can be an option. The winch allows the tractor to stay on a road or trail, which reduces soil compaction and disturbance. Some special attachments are now made to adapt all-terrain vehicles for skidding smaller logs. Log loading can be done with a farm tractor’s front-end loader equipped with forks or tines. Farm tractors can also pull specially built trailers equipped with an attachment that loads the logs and keeps them off the ground (forwarding). This will minimize any ground disturbance.

 Conventional logging systems

    Traditional logging systems in West Virginia use manual chain saw felling, limbing, and topping; then skidding to a landing; bucking into log lengths; sorting for specific products; and finally loading onto a truck or trailer. Several variations of this system are used depending on site conditions, season, and contractor preference. In many situations, these conventional logging systems have as much potential for reduced site impact as any alternative system if the owner, supervisor, and operators are trained, take careful measures, and have the “right” attitude.   Conventional logging systems using smaller skidding machines cause less damage to remaining trees and provide improved profitability on stands with smaller diameter timber. A 1999 U.S. Forest Service study found that matching machine size to size of wood allows timber stands with smaller diameter trees to be economically harvested earlier, thereby adding value and quality to the future stand. The smaller machines with their tighter turning capabilities and lower weights should result in less stand and site impact if operators are carefully trained and conscientious.

 Cut-to-length systems

    Cut-to-length systems use combinations of tracked or wheeled harvesters and forwarders. These systems have become very popular in some areas of the country. Several loggers in West Virginia use them. The machines in these systems typically cost well over $100,000 each and can approach $200,000 or more. They operate on larger tracts where sufficient timber volume supports their relatively high operating and ownership costs. These high-tech machines can leave very gentle “footprints” in a variety of difficult terrain and conditions. Although production rates are usually less than with some conventional systems, they can operate with less disturbance on wet sites and steep slopes. Because these systems are usually operated with smaller crews, they can be owner operated or family companies. 

    The tracked harvester reaches out with its arm to select the trees marked for harvest, reducing damage to residual trees. The machine operates on tracks that minimize rutting. It is also much safer for the feller since he is in a protected, environmentally controlled cab. After the felling machine cuts the tree, it usually will pick up and place the stem in a position for bucking and delimbing. Some machines have special processing heads that can delimb and cut to proper log lengths based on information in an on-board computer. After delimbing and bucking, a forwarder will use its loading arm to pick up the logs and then haul them to the deck or landing. This forwarding function is a major difference from a conventional logging system. In a conventional system, the logs would be dragged to the landing by a skidder.  Dragging the logs disturbs the soil, which can increase the potential for erosion.

    Using forwarders to carry logs rather than skidders that drag logs can also reduce the number and density of necessary roads. This in itself will reduce impact to the site and stand. Because forwarders carry logs on wheels, they can be driven on truck roads without causing damage and can usually operate economically at farther distances than conventional skidding. Forwarders are equipped with six to eight large wheels, resulting in a low ground pressure and minimizing ground impact. Lowering tire pressure, adding chains or tracks, and putting on wider tires or bogies can all help reduce ground impact in special situations. Many combinations of harvesters, skidders, forwarders, and loaders are used, depending on local site conditions, markets, and customs. The logs can then be piled or directly loaded on a truck or trailer.

 Best fit

     Four general low-impact logging systems that can be gentle on the land, trees, and overall environment have been described in this article. No one system can be said to be the “best” in all circumstances. It is critical to match the logging system with the harvest and management plan, landowner desires, site, and stand characteristics.

    Perhaps the most important factor in any system is the care, training and dedication of the contractor and operators doing the work. Many conventional or traditional West Virginia logging contractors already use low-impact practices. A logger’s attitude can be more important than size or type of equipment. Even horse logging can cause skinned trees if not done carefully. Landowners who demand certain special practices must understand that there is an added cost to the logger. Loggers who make specific efforts to lower impacts may need to be paid incentives or higher logging rates.

    The real challenge is logging smaller woodlots in a sustainable manner using  low-impact methods. It is in these smaller woodlots that minimizing damage to the residual trees and site is especially necessary. The left trees are the growing stock for the future stand and as such are extremely valuable. The growing stock that is left should include valuable species with good form, quality, health, and potential for growth. In some ways, managing smaller woodlots is more challenging than larger acreages since there is little room to compensate for negative practices. Landowners using gentle logging methods will have much satisfaction and pride, along with periodic income from their forest.