Objectives of Tending Operation – Thinning
1) To Improve the Hygiene of the Crop:
By removing dead, dying and diseased trees, hygiene or health of tree can be maintained well.
2) Salvage of Anticipated Losses of the Merchantable Volume:
A large number of trees die of suppression. This amount contributes of about 20 per cent of the merchantable volume. Thinning contributes a substantial amount in the total yield of crop. Thinning helps in shortening of the rotation. Reduction in number of trees in thinning increases the diameter of the remaining trees.
3) To assure the Best Physical Conditions of Growth:
The objective of the thinning is to keep growing stock somewhere within the range. The effect of extreme competition is reflecting by decline in the rate of growth with increasing density in crops which are very dense. Thinning increase the diameter of the crops. Thus thinning may be essential tool for shortening the rotation of a crop.
4) To Obtain Desired Crop:
Thinning helps to improve the stand structure. It ensures a uniform and proper distribution of trees all over the area. This enables the trees to tap water and nutrients from a larger area. The composition of the crop can also be improved. The less valuable species may be removed in thinning and the important and valuable species may be retained for future.
5) Improvement of Stand Composition, Regeneration and Protection:
If an undesirable species is not eliminated during regeneration stage it can be done during thinning to a certain extent. Thinning helps in obtaining suitable seed bearers for obtaining successful regeneration. The dead, drying and diseased trees are removed to afford protection from insect pest, disease and fire because these trees may serve as a source of infection.
6) Improvement in Wood Quality:
Thinning may also improve the quality of wood because trees with higher diameter are likely to be of better quality than smaller ones.
7) To Increase Net Yield and Financial out turn from a Stand:
Thinning help to obtain returns early. The sale of thinning material helps to reduce investment burden because of early returns from thinning and shortening of rotation.
8) To Help Decomposition of Raw Humus:
In temperate forests, thinning increases light and temperature on the forest floor and causes mechanical disturbance which help the decomposition of raw humus and release of nutrients, etc.