The sustained yield concept dictates that whenever timber is removed, either by block cutting or by selective cutting, the denuded area must be reforested. Similarly, any forested land which has been destroyed by fire or mining activities should be reforested.In rugged terrain aerial seeding is the method of choice.But, now more than one-third of this area has been robbed by man of its natural protective cover and has been turned into barren land.
Some of the fire suppression techniques are to develop three metre wide five lanes around the periphery of the fire, back fires, arrangement of water spray, fire retardant chemicals should be sprayed from back tank and if possible by helicopters.
There must be a trained staff of firefighters to control the fire.
In that case, trees of same age group can be cut down in a selected area and then marked for replantation.
In selective cutting only mature trees are selected for cutting. Shelter wood cutting is where first of all useless trees having been cut down followed by medium and best quality timber trees.
During the colonial period commercial exploitation began and this was the main cause of the depletion of forests.
The commercial use of forests nowadays has reached such an extent that it has become a threat to the environment in the form of: (i) Increase in temperature, (ii) Lesser precipitation, (iii) Increased rate of soil erosion, (viii) Imbalance in ecosystem.
The forest can be managed in such a way that a timber crop may be harvested indefinitely year after year without being depleted.
This technique is called the ‘sustained yield’ method adopted by many countries of the world.
Therefore, cutting should be regulated by adopting methods like: (i) Clear cutting, (ii) Selective cutting, and (iii) Shelter wood cutting.
The clear cutting method is useful for those areas where the same types of trees are available over a large area.