logging
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidder, skidding, on-site processing, and loading of trees or trunk (botany), logs onto logging truck, trucksclearcuts, and are instead considered a form of
selection cut
Selection cutting, also known as selection system, is the silvicultural practice of harvesting trees in a way that moves a stand level modelling, forest stand towards an uneven-aged or all-aged condition, or 'structure'. Using stocking models der ...
. A typical patch cut might be 2-3 tree lengths. Below a certain size, seedling regeneration advantage shifts from the shade intolerant species favored in clearcuts to the shade tolerant species favored by selection harvests.
An areas of patch cuts of different shapes were tried in the Northern hemisphere to see where shade tolerant and shade intolerant species might regenerate. It was found in small patches (1/10 acre) N. 44° that there was a limited solar exposure of only a few hours (3-4) and this would lead to strongly shade tolerant and moderately shade tolerant trees dominating over time. Yet at slightly larger (1/2 acre) patches much more sunlight for longer was reaching the forest floor. This would warm the floor more, increase nutrient release and thus more light demanding species could grow faster and might then reach maturity in the stand.
As well as light other factors to be considered are wind to avoid
windthrow
In forestry, windthrow refers to trees uprooted by wind. Breakage of the tree bole (botany), bole (trunk) instead of uprooting is called windsnap. Blowdown refers to both windthrow and windsnap.
Causes
Windthrow is common in all forested ...
,
pathogens
In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ.
The term ...
and fire risk. Positive benefits can also be gained if patches keep horizontal biodiversity in a forest stand and for an owner with not so much forest this may be useful for keeping
non-timber forest product
Non-timber forest products (NTFPs) are useful foods, substances, materials and/or commodities obtained from forests other than timber. Harvest ranges from wild collection to farming. They typically include game animals, fur-bearers, nuts, see ...
s in usable amounts.
Patch cuts can have less visual impact than clearcuts, and can mimic some stand disturbance processes. Patch cuts can also be simpler to implement than trying to selectively log individual trees within a selection cut.
Patch cuts are distinct from the group selection method. A patch would pick several trees to be big enough to allow regeneration of a specific species, perhaps that has problems growing due to shade intolerance or another factor, as several together. Whereas a group would be only a few mature trees (3-5) and would not necessarily favor a shade intolerant species to establish into a group. In a patch the edge effect would be overcome but in a group most likely not.Silviculture: Concepts and Applications 2nd Edition by Ralph D. Nyland Chapter 11
Patch cuts may be used in a hybrid system with the single tree selection cut method or the group tree selection cut method.
See also
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Shelterwood cutting
Shelterwood cutting removes part of the old forest stand to allow for a natural establishment of seedlings under the cover of the remaining trees. Initial cuttings give just enough light to allow for the regeneration of desired species. Subseque ...
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Silviculture
Silviculture is the practice of controlling the growth, composition/structure, as well as quality of forests to meet values and needs, specifically timber production.
The name comes from the Latin ('forest') and ('growing'). The study of forests ...