Understanding Common Forestry Cutting Methods

Forestry cutting methods are crucial for sustainable forest management. These techniques vary widely depending on ecological, economic, and social factors. In this article, we will explore the three most common methods: under cut, back cut, and fore cut, while also discussing broader categories used in different forest types.

The Three Common Forestry Cutting Methods

Under Cut, Back Cut, and Fore Cut

The three primary cutting methods used in forestry are under cut, back cut, and fore cut. These methods are often employed to fell large trees safely and efficiently.

Under Cut: The under cut, also known as the undercut, is the first step in the felling process. It involves removing wood from the base of the tree on the side where the tree is intended to fall. This creates a wedge of wood that allows the tree to be pushed over when cut. The cut is made at an angle, typically about 30 degrees, to the trunk of the tree. Back Cut: Once the under cut is complete, the next step is to make the back cut. This cut is made on the side opposite the under cut, on the edge of the tree. The back cut is crucial because it, along with the under cut, will cause the tree to fall. It should be made at a 90-degree angle to the under cut. Fore Cut: The fore cut, also known as the felling cut, completes the process by making the final cut just above the under cut. This ensures that the tree will fall as intended without any unexpected movements. It is critical to ensure all cuts are parallel and clean to prevent the tree from splitting.

These three cuts work in unison to safely and effectively fell a tree. Each cut is necessary to achieve a controlled fall and minimize the risk of damage to nearby trees or property.

Common Harvesting Methods in Different Forest Types

While we have highlighted three primary forestry cutting methods, it's important to note that the field of forestry encompasses a wider spectrum of techniques. These methods can be broadly categorized into three major categories: clear-cutting, individual tree selection, and thinning. Each method has its unique applications and is most effective under specific circumstances.

Clear-Cutting

Clear-Cutting

Clear-cutting is a comprehensive method often used in even-aged forest plantations. It involves the complete removal of trees within a defined area, typically in strips or patches, with the number of subdivisions equal to the forest's rotation age. This method is often ecologically beneficial, as it promotes new growth and maintains ecological balance. However, it can face strong public opposition for its perceived environmental impact.

Individual Tree Selection

Individual Tree Selection

Individual tree selection is a more selective approach that involves the careful removal of individual trees based on specific criteria. This method is typically used in forests with diverse aged trees. Although appropriate in certain circumstances, repeated selective cutting can lead to an unhealthy forest condition. This method was initially developed in 18th century Europe to manage post-war forests.

Thinning

Thinning

Thinning is a method that reduces tree density, aiming to improve the growth and health of remaining trees. It is often misunderstood as merely removing understory trees. However, thinning involves various techniques, including low thinning (removing understory trees), high thinning (removing some of the overstory trees), and variable density thinning (a combination of both). Another innovative practice is group selection, which involves creating small clearcuts to promote natural regeneration and biodiversity.

The US Forest Service is implementing group selection in the coastal forests of the Pacific Northwest, aiming to convert maturing clearcuts into old-growth conditions within a short timeframe. While purists debate the authenticity of these man-made old-growth forests, they do attract a diverse range of wildlife species.

Conclusion

Finding the right forestry cutting method is a complex process that requires careful consideration of ecological, economic, and social factors. From the basic under cut, back cut, and fore cut techniques to the broader methods of clear-cutting, individual tree selection, and thinning, each method serves a unique purpose in forest management. Understanding these techniques is essential for sustainable forestry practices and the preservation of our natural environment.