Silviculture is the art and science of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values of landowners and society on a sustainable basis.
Regeneration
Forest regeneration refers to the establishment of
seedlings following a natural disturbance or a prescribed management activity. Establishment can be either natural or artificial. Natural establishment occurs through newly
germinating seeds or resprouting of cut
stems. Artificial establishment involves planting of tree seedlings or seeds.
Thinning
The goal of thinning is to control the density, composition, and quality of tree stands and to improve
tree growth, especially of the diameter, by providing additional growing space for the remaining trees. It also provides an opportunity to cull the commercially less desirable, usually smaller and malformed, trees.
Pruning
Pruning, as a silvicultural practise, refers to the removal of the lower branches of the young trees so clear
knot free wood can subsequently grow over the branch stubs. Clear knot-free
lumber has a higher value. Pruning has been extensively carried out in the
Radiata pine plantations of
New Zealand and
Chile, however the development of
Finger joint technology in the production of
lumber and
mouldings has lead to many forestry companies reconsidering their pruning practices.
Common Silvicultural Regeneration Methods
Clearcut
The removal of all trees in a single cut with the goal of establishing new forest
reproduction from artificial or natural means.
Seed tree
The removal of most trees in a single cut with a few are being retained to provide a source of
seed for the natural regeneration of the forest. Generally, these retained seed trees are removed following the establishment of the new forest.
Shelterwood
The removal of trees in a series of cuts to establish new forest reproduction under the shelter of the retained seed trees. The main difference between the shelterwood and seed tree methods is that the residual trees in a shelterwood alter the enivironmental conditions, such as
sunlight,
temperature, and moisture, for tree seedling growth, while the few retained trees in a seed tree method do not. Commonly the shelterwood method involves three cuts:
- Preparatory cut
- Establishment cut
- Removal cut
Selection
The removal of scattered individual trees or groups of trees with the goal of creating and maintaining an uneven-aged forest structure.
See also
References
- Daniel, T. W., J. A. Helms, and F. S. Baker 1979. Principles of Silviculture, Second Edition. McGraw-Hill, New York. 521 p. ISBN 0070152977
- Nyland, R. D. 1996. Silviculture, Concepts and Applications. The McGraw-Hill Companies, Inc. New York. 633 p. ISBN 0070569991
- Nyland, R. D. 2002 Silviculture: Concepts and Applications, Second Edition. The McGraw-Hill Companies, Inc. New York. 704 p. ISBN 0073661902
- Smith, D. M. 1986. The Practice of Silviculture, 8th edition. John Wiley & Sons, Inc., New York. 527 p. ISBN 0471800201
- Smith, D. M., B. C. Larson, M. J. Kelty, P. M. S. Ashton. 1997. The Practice of Silviculture, Applied Forest Ecology, 9th edition. John Wiley & Sons, New York. 560 p. ISBN 047110941X
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