Equipment Specs
Content
Languages
(Redirected from Shelterwood)

Shelterwood Cutting

From RitchieWiki

(Redirected from Shelterwood)
Forestry Processes

Shelterwood cutting is a silviculture system ideal for trees tolerant to partial-shade conditions or for trees that have adapted to natural events that tend to destroy or damage some, but not all of, the trees within a stand.[1] The objective of shelterwood cutting is to use older, mature trees in a stand as a protective cover over a developing even-aged stand of new trees.

[edit] Process

Harvesting a shelterwood stand is carried out in a series of cuts with each cut meeting a specific objective. Sometimes cutting can span a period of 10 to 30 years.[2] The process of cutting in its entirety is designed to foster growth through seeding. Subsequent and staggered cutting also serves to thin the forest canopy gradually as needed to maximize the potential of partial shade and sunlight in the regeneration of new trees situated in the lower part of the forest.

The first cut made is a preparatory cut similar to low commercial thinning. The first cuts take place in the lower level of the forest canopy and encourage seeding. An establishment cut is then made with the intention to provide enough space and shelter for the development and growth of young seedlings. Sometimes a preparatory cut may be overlooked with the establishment cut being the first cut made in a stand. Removal cuts occur in shelterwood harvesting after regeneration has started and is well established. The protection provided by the forest crown is no longer needed and removed. If the crown of mature trees is not harvested at the right time, it can begin to hinder the regeneration process of a new tree stand. The last cut to be made is usually a salvage cut that involves a non-uniform commercial thinning to remove windthrow and insect infested, diseased, or dead timber.[3]

[edit] Types

Strip shelterwood is a system that involves a series of progressive, linear cuts in narrow successive strips. The basic reasons for this type of system is to lessen the damaging effects on the residual stand from elements such as wind and to maximize shading of cut strips by the uncut areas.[4]

Uniform shelterwood is a system that consists of individual leave-trees that are spaced in a uniform configuration throughout a stand.[5]

Group shelterwood is a system by which small openings are established in the stand in a manner such that adjacent trees provide shelter for new regeneration. Groups of leave-trees eventually decrease with gradual harvesting until all the mature trees have been removed.[6]

Irregular shelterwood is a system that incorporates the features of other shelterwood systems. One distinct characteristic of the irregular shelterwood system is that residual trees are left in a stand long after the regenerative phase. The residual trees are used to foster new age classes of regeneration, accumulate wood volume increment, and sometimes to accomplish non-timber stand objectives.[7]

Natural shelterwood is when natural processes dictate the establishment and development of a two-aged stand consisting of an understory of new-growth trees under a canopy of older, mature, even-aged trees.[8]

[edit] References

  1. Silvicultural Systems. Ontario Ministry of Natural Resources. 27-05-2009.
  2. Silvicultural Systems. Ontario Ministry of Natural Resources. 27-05-2009.
  3. Shelterwood System. Even-aged Silvicultural Systems. BC Ministry of Forests, Forest Practices Branch. 27-05-2009.
  4. Silvicultural Systems Guidebook. Government of British Columbia. 27-05-2009.
  5. Silvicultural Systems Guidebook. Government of British Columbia. 27-05-2009.
  6. Silvicultural Systems Guidebook. Government of British Columbia. 27-05-2009.
  7. Silvicultural Systems Guidebook. Government of British Columbia. 27-05-2009.
  8. Silvicultural Systems Guidebook. Government of British Columbia. 27-05-2009.