Advance silvilculture iof

Unit-1
Introduction
1.1 General introduction about the systems
1.2 Classification and concepts of silvilcultural system
Unit-2
Major silvicultural systems and their advantages and disadvantages
2.1 Clear felling system
2.1.1 with artificial regeneration
2.1.2 with natural regeneration
2.2 Seed tree system
2.3 Shelter wood system
2.3.1 Uniform systems
2.3.2 Group
2.3.4 Strip
2.3.5 Irregular
2.4 Selection system
2.4.1 Single tree selection
2.4.2 Group selection system
2.5 Accessory systems
2.5.1 Two storied high forest system
2.5.2 High forest with reserves system
2.6 Coppice system
2.6.1 Simple coppice
2.6.2 Coppice with standards
2.6.3 Coppice with reserves
2.6.4 Other variations of coppice systems
2.7 Conservation
2.7.1 Objectives of conversion
2.7.2 Techniques of conversion
2.7.3 Examples of conversion
Unit-3
Choice and formulation of silvilcultural systems
3.1 Factors to be considered while selecting and formulating a system
3.1.1 Identification of objectives of management
3.1.2 Provision for regeneration
3.1.3 Efficient use of growing agencies
3.1.4 Provision for sustained yield
3.1.5 Control of damaging agencies
3.1.6 Optimum use of forest capital
Unit-4
Application of silvilcultural systems
4.1 Silvilcultural systems applicable to following forest types: Sal, Asna, Khair-Sissoo, Katus Chilaune, Utis, Oak, Chir pine, Spruce,
Fir, Deodar
Unit-5
Silvilfultural systems and practices in Nepal
5.1 Nation forest
5.2 Community forestry
5.3 Leaseholds forest
5.4 Religious forest
5.5 Private forest
5.6 Bufferzone forest
Advance Silvilculture Compiled MHK & DG IOF,POKHARA Page 1

Unit-1
Introduction
1.1 General introduction about the systems
1.1 General introduction about the systems;
Definition:
Silvilculture is the art and science of cultivating forest crops. In broad sense, silviculture includes both silvics and its practical application.
Silvics:
Silvics is the study of life history and general characteristics of forest trees and crops with particular reference to environmental factors as
basis for the practice of silvlculture. Silvilculture can be described to include all practical and theoretical aspects of silvics. The knowledge
gathered in silvics is applied to the production and care of forest crops.
Thus, the practice of silvilculture is applied silvics. The practice of silvilculture is concerned with the social as well as the biological aspects
of forestry. The important objective of forestry is to make forests useful to society.
Objective of silvilculture;
The objective of study and practice of silvilculture is to produce more useful and valuable forests to meet our requirements in a shorter time.
The study of silvilculture helps to attain the following objectives;
1. Production of species of economic value.
2. Production of more volume per unit area
3. Production of high quality timber
4. Reduction of rotation period
5. Raising forest in blank areas.
6. Creation of plantation
7. Introduction of exotics
8. Increase in employment potential
9. Increase in production of fuel and fodder
10. Development of forest industries
11. Derive environmental benefits
1. Production of species of economic value;
The production of timber species of economic value per unit area is low. If the forests have to produce timber of industrial and economic
importance, it is necessary to study and practice of silvilculture so that we can produce only the desired species.
2. Production of more volume per unit area:
In the virgin forest the crop is generally either very dense or very open. Both these extremes are unsuitable for quantitative production. The
study and practice of silviculture helps in raising sufficient trees per unit area right from the beginning to fully utilize the soil and as they
grow up gradually reduce their number so that the requirement of light and food of the remaining tree is met. In this way silvilculture helps to
bring the production of more timber per unit area on a sustained basis.
3. Production of high quality timber:
In the unmanaged forest because of much competition a large number of trees become crooked, malformed, diseased and defective.
Silvilculture techniques help to avoid these problems and to produce timber of a very high quality. Thus knowledge of silvilculture is
essential to ensured disease free timber production.
4. Reduction of rotation period:
Rotation is the planed period of time expressed in years between the regeneration of a crop to its final felling. In unmanaged forests rotation
tend to be longer because the growth of individuals’ tree is retarded. There is intense competition and it takes the trees a longer time to attain
an exploitable size. With the knowledge and practical application of silvilcultural techniques density of the crop can be properly regulated
and consequently the rate of growth increased and rotation reduced.
5. Raising forest in blank areas:
In nature a large number of areas potentially suitable for tree growth, remain blank due to certain adverse factors inhibiting growth of trees.
Silvilcultural skills and techniques help in raising forest in such areas.

6. Creation of plantation:
Plantations may be created in place of natural forest. This can be brought about under conditions where the natural forest has failed to
regenerate itself or when the existing forest is too slow growing for exploiting its potential to the optimum extent possible.
7. Introduction of exotics;
Knowledge of silvilculture is highly beneficial for the successful introduction of exotic species for industrial environmental or related
purpose e.g. Eucalyptus, Populus and Teak etc
8. Increase in employment potential:
Increased employment potential is clearly one of the objectives of modern silvilcultural techniques. In any plantation operation, the labor
component accounts for between 60-70% of the total financial input.
9. Increase in production of fuel and fodder:
Silvilcultural techniques help to bring about an increase in the production of fuel wood and fodder from the forest both of which are very
essential for a developing country like Nepal.
10. Development of forest industries;
Silvilculture contributes to the development of the industrial potential of a region as forests provide important raw materials e.g. Resin,
pulpwood, industrial wood and minor forest products for various forest-based industries.
11. Derive environmental benefits;
Silvilculture helps to raise forests so that human beings may drive maximum environmental benefits from them such as soil and water
conservation, control of air and noise pollution, wild life conservation, regulation of climatic conditions and regulation of water cycle.
Silvicultural Systems
 Silvicultural system may be defined as a method of silvicultural procedure by which forests are harvested, regenerated and tended.
 It is a planned silvicultural treatment, which is applied to a forest crop throughout its life to get a distinctive form.
 It begins with regeneration felling and includes adoption of some suitable method of regeneration and tending of the new crop
throughout of its life.
 A silviculture system is a silvilcultural procedure adopted for renewal of a forest crop in a given set of conditions.
 Thus, it is just a technique perfected on the basis of knowledge of silviculture, but its application is governed by the requirements
of forest management or to achieve the objectives of forest management.
 A silvicultural system deals with the removal of a forest crop, its replacement with a new crop of distinctive form, and its tending.
It has the following essential characteristics
The pattern of felling to be adopted in harvesting a mature crop to be regenerated:
It includes felling of a single tree to clear felling; the pattern of felling depends on:
1. Silvicultural requirement of the species to be regenerated
2. Intensity of demand of forest products
3. Development of communication and other local conditions
The pattern of felling affects the form or character of the new crop. I.e. even aged and uneven aged. These form the basis of
classification of silvicultural system.
Classification of Silvicultural Systems
Silvicultural systems have been classified in a variety of ways but the most commonly used classification is based primarily on the mode of
regeneration and further classified according to the pattern of felling carried out in the forest crop. According to the method of regeneration
silvicultural systems are of following two types:
1. High Forest System
2. Coppice Systems

1. High forest systems:
Those silvicultural systems in which the regeneration is normally of seedling origin, either natural or artificial or a combination of both and
the rotation is generally long
The high forest systems and coppice systems are further classified on the basis of pattern of felling and mode of regeneration as well. A
schematic classification of these systems is given here.
High Forest Systems
Systems of Concentrated Systems of Diffused Accessory Systems
Regeneration Regeneration
1. Two storied High Forest
2. High forest with Reserve
3. Improvement felling
Clear felling system Shelter wood system Selection system
1. Clear felling system 1. Uniform system 1. Single Tree system
2. The clear strip system 2. Groups system 2. Group system
3. The alternate strip system 3. Irregular shelter wood system
4. Indian irregular shelter wood system
2. Coppice System (Low Forest System)
1. Simple Coppice System.
2. The Coppice of Two Rotation System.
3. The Shelter wood Coppice System.
4. The Coppice with Standards System.
5. The Coppice with Reserves System.
6. The Coppice Selection System.
7. The Pollarding
1. High Forest Systems:
Those silvilcultural system in which the regeneration is normally of seedling origin, either natural or artificial or a combination of both
and the rotation is generally long. These are further classified a follow on the basis of pattern of felling.
1. Clear Felling System
2. Shelter wood system
3. Accessory systems

Unit-2
Major silvicultural systems and their advantages and disadvantages
2.1 Clear felling system
2.1.1 with artificial regeneration
2.1.2 with natural regeneration
2.2 Seed tree system
2.3.1 Uniform systems
2.3.2 Group
2.3.4 Strip
2.3.5 Irregular
2.5 Accessory systems
2.5.1 Two storied high forest system
2.5.2 High forest with reserves system
2.6 Coppice system
2.6.1 Simple coppice
2.6.2 Coppice with standards
2.6.3 Coppice with reserves
2.6.4 Other variations of coppice systems
2.7 Conservation
2.1 The clear felling system:
 The clear felling system is defined as a silvicultural system in which equal or equi- productive areas of mature crop are
successively clear-felled in one operation to be regenerated most frequently, artificially but sometimes naturally also.
 The area to be clear-felled each year in uniformly productive sites is l/n of the total area allotted to this system’s
 Where n = no of years in the rotation and is usually referred to annual coupe.
 The regenerated crop is absolutely even aged. The coupes to be felled every year are made equi-productive.
According to the definition, the entire crop of the coupe should be felled and removed in one operation, but in practice following
variations are observed:
1. Some mature trees are retained as a frost protection measure or as insurance against failure. Such trees are also sometimes
retained to serve as a nurse crop to facilitate establishment of frost-tender species.
2. Promising groups of saplings and poles are retained to prevent unnecessary sacrifice of immature crop of the desired species.
Isolated saplings or poles are generally not retained as they develop in to wolf trees.
Removal or felling of mature crop:
Variations:
Retention of some matured trees as a frost protection measure or as an insurance against failure, through from the point of view of both
these objects, their number is very small. Sometimes retained to serve as a nurse crop
According to definition, the entire crop of the coupe should be felled and removed in one operation but in practices following variations
are observed.
1. Retention of some mature trees as frost protection measures or as and insurance against failure or as nurse crop to facilitate
establishment of forest tender species.
2. Retention of promising groups of saplings and poles to prevent unnecessary sacrifice of immature crop of the desired species.
3. Isolated saplings and poles are ordinarily not retained as they may develop in to wolf trees.
Methods of obtaining regeneration: the area can be regenerated sometimes naturally but mostly artificially:
2.1.1 Artificial Regeneration
2.1.2 Natural Regeneration

1. Method of Artificial Regeneration: Artificial regeneration is preferred due to following reasons
1. It is the surest and quickest method of improving crop composition.
2. It facilities introduction of fast growing and high yielding exotics.
3. It provides better financial returns.
4. The regeneration is established sooner, so the area can be opened for grazing sooner.
Advantages of AR:
 It is the surest and quickest method of improving crop composition which remains under strict control.
 It facilitates introduction of fast-growing and high yielding exotics.
 It completes regeneration operation quickly, and therefore results in considerable in cost of formation and in better financial
return.
 As the regeneration is established sooner artificially thanit does naturally, and the area can also be opened for grazing sooner.
Artificial regeneration can be done through:
1. Departmental plantation
2. Taungia
a. Departmental Taungia
b. Leased Taungia
c. Village Taungia
1. Departmental Plantation:
Demarcation of annual coupe
• all trees are marked and enumerated
• a stock of the area is prepared
• the trees to be retained are ringed and serially numbered.
• the marked trees are auctioned
• sale rules guides the contractor for cleaning and burning of the felling refuse.
• felling and exporting forest products will be regulated by the sale rules.
After the area is cleared, it is inspected and a soil map as well as a treatment suitability map is prepared
• during this inspection, the method of soil working (pits, trenches and the alignment) are sown.
After soil working the area is fenced.
• soil dug up in soil working is kept by the side of the pit, in slopes on their lower side.
• soil working should be completed at least a month before.
• after weathering, the soil is filled back in the pit.
• sowing is done before the rain start and planting is done when the rains have set in.
• in hills the winter sowing and planting is also done before snowfall.
After this the plantation is kept well weeded during the rains and protected against fire during summer.
2. Taungia:
Taungya
It is a method of raising forest plantations in combination with field crops. The taungyas may be,
• departmental –done by the department, E.g., Tamagadhi
• leased or village taungyas- agricultural crops are raised in the interspaces of the lines of the forest
plants by giving the land on lease money. Village taungyas are those taungyas which are raised by
villagers who have settled by down in a village inside the forest for the purpose. It has following
advantages:
a) Reduction of burden of work on forest staff;
b) Realization of sufficient lease money to cover the entire expenditure on plantation; and
c) Suppression of weeds and grasses without expenditure.
2. Method of Natural Regeneration: Natural regeneration may be from seeds or from advanced growth already present on the site or
seeds brought from outside by natural means. Some methods of obtaining natural regeneration:
Natural regeneration from seed: The area may get seed form one of the following sources:
1. Seeds stored in the area

2. Seeds received from outside
3. Natural regeneration from advanced growth
1. Seed stored in the area;
Essential condition for the success of this method is the prolonged viability of the seed, or seed ripening should coincide with the
felling so that latter may result in dispersal of seed required for regeneration of the area.
Example; Teak but its natural regeneration from seed is rarely relied upon.
2. Seed received from outside
Natural regeneration can also be obtained if seed can reach the coupe from outside after clear felling.
Example; Babul seeds from advance growth retained are flooded with flood waters in Indus river, the area gets profuse natural
regeneration Sind, Pakistan.
3. Natural regeneration from advance growth
The reliable method of natural regeneration of the coupe after clear-felling is from advance growth, i.e., established seedlings, saplings
and young pole of the desired species already present in the coupe before clear-felling. Seedling coppice is an operation carried out in
stagnating or damaged seedlings to give well-grown new crop.
Example; Sal in Singhbhum
TENDING
The weeds are all destroyed by one or two effective burns given before soil working, they appear again by the time of sowing or
planting is started. As the weeds affect the growth of plants of the desired species, the plantations have to be kept well weeded. The
number of weeding depends upon the rate of growth and density of the weeds, as well as the rate of growth of the forest plants as:
Weeding intensity and other operations:
Year Planting Sowing Other tending operations
First Two weedings Three weedings Spacing of plants of desired species, hoeing of soil
and climber cutting are also done.Second One weeding Two weedings
Third One weeding One weeding
Note: In village taungyas, weedings are done from 5th
year onward; cleanings and thinning are carried out, initially on 5 or 10 years
cycle.
Objective of the tending:
To allow plants of the desired species to grow rapidly so that they are established and their canopy closes as early as possible.
CHARACTER OF THE NEW CROP
The crop is absolutely even-aged and, if there are no accidents or failures, the system gives a normal series of age gradations
Advantages:
1. It is simplest of all high forest system. It does not require a high degree of skill.
2. As felling is concentrated, the yield per unit area is more and consequently the cost of felling and extraction is low.
3. Introducing fast growing exotics and regulating composition of new crop through artificial regeneration is advantageous.
4. It makes the supervision of all operations easy.
5. There is no damage to new crop by felling.
6. If properly tended the even aged crop produced have trees with cleaner and more cylindrical boles.
7. Entire crop is regenerated in one operation. Its establishment is quicker there by reducing the cost and rotation.
8. As the regeneration establishes early, the coupe can be opened up for grazing soon.
9. The distribution of age class is very regular.
10. The success or failure of regeneration is clear by the end of first year or in few years.
Disadvantages:
1. It is the most artificial system.
2. Soil remain open there is more danger of soil deterioration and erosion
3. The danger of weeds and grass invasion increases.
4. It produces even aged crop, which is less resistant to damage by wind.

5. When the crop is pure it becomes more susceptible to damage by Insects, plant parasites and pathogens.
6. It sacrifices all immature crops that may still be putting on valuable increment.
7. Growing space and site factors are not fully utilized.
8. Annual yield is less than uneven aged crops.
9. This system is not suitable on hilly area and slopes.
10. The system is aesthetically very bad.
Considerations for applications:
These considerations are:
1. Factors of locality:
The climatic factors in general and microclimate in particular, affect the choice of species. In case of exotics, bio-climate factor of the
new locality favorably with that of their home-land. Similarly, temperature, photo-period, rainfall, humidity, affect the plant growth
and so their effect should be properly assessed. Geology and soil also affect the system. The biotic factors are also equally important in
our country.
2. Potential productivity of site:
It is necessary that potential productivity of the site is assessed and the silvicultural technique suitably modified to ensure rapid growth
of new plants after felling. For example, highly productive requires less input compared to sites of low potential productivity and it is
also imperative that necessary inputs are judiciously applied.
3. Species and composition of crop:
Though clear-felling system is most suited to light demanders, but when this is done, care should be taken to ensure that the choice of
species has been correctly made and that only genetically superior seeds or plants are used.
4. Regeneration:
The success of any system depends entirely on the success of regeneration. If regeneration is not assured, the system is not assured, the
system is a failure. The clear-felling system followed by artificial regeneration is the only system by which areas which cannot be
naturally regenerated satisfactorily, and in a reasonably short time, by any other high forest or coppice system, can be regenerated.
Adequate quantities of genetically superior seed or plants, as also sufficient labour to complete the work in time, should be arranged
well in time.
Example of Application:
I. Clear felling followed by Artificial Regeneration;
Regeneration may be obtained either by departmental plantations or by taungyas.
a) Departmental plantations
i. Allapalli techniques for teak - advance growth & NR of teak,
ii. Casuarina plantatons - naked root / ball of earth / container plantation & watering till third year,
iii. Cryptomeria and Cupressus plantations of West Bengal – planting of naked root plants raised in nursery is
done in pits.
b) Taungyas
i. Sukuna (Kurseong division) technique for sal – Every nine lines of sal, 3 lines of miscellaneous species are
raised with inter cultivation.
ii. Nilambur technique for teak
One and half year advance work of teak stump planting time and short stalked paddy growing in 2 hector
lease plots,
iii. Gorakhpur technique for sal- cultivators cultivate agricultural crops for four years till adequately stocked
with sal saplings about 1m height.
II. CLEAR-FELLING FOLLOWED BY NATURAL REGENERATION
i. Natural regeneration by seed stored in area
Acacia mollisima produces large quantities of annually in Tamil Nadu, India.
ii. Natural regeneration by seed received by outside
Mangrove forest of Andhra Pradesh are managed with all advance growth under 2.5 cm in diameter is retained at
the time of clear-felling.
iii. Natural regeneration from advance growth

a. North Betul (MP) technique for teak – Teak working circle with conversion to uniform, as a part of the
unconverted forest is worked under selection system.
b. Saranda (Bihar) technique for Sal – The silvicultural system adopted is clear-felling followed by natural
regeneration. In the areas allotted to P.B.I., which have prolificand complete established advance growth.
c. South Raipur (MP) technique for sal - The silvicultural system adopted is conversion to uniform, the work
done in P.B.I is clear-felling followed by natural regeneration.
VARIATIONS FROM THE STANDARD TECHNIQUE OF CLEAR-FELLING SYSTEM
A typical clear-felling system stipulates clear-felling of old crop and production of an even-aged crop. But now a day this retention
creates two kinds of deviation from the standard of clear-felling system:
a) The pattern of felling does not conform to clear-felling, and
b) The crop produced becomes uneven-aged.
EXAMPLES OF CLEAR-FELLING WITH RETENTION OF SHELTERWOOD
a) Haldawani Division (U.P.) technique for teak in planting series II
b) Kulu and Rohru Divisions (HP) techniques for fir and spruce
THE CLEAR-STRIP AND THE ALTERNATIVE-STRIP SYSTEMS
It is not always possible to clear-fell the whole of a compartment/ sub-compartment in one operation, in such cases clear-fellings are
done in the form of strips. The objects may be:
i. To regenerate the area naturally by seed from adjoining areas,
ii. To protect the young crop against wind, snow, insolation, insect or fungal attack,
The clear-felled strips may be arranged in two ways:
i. Progressively in one direction, known as the clear-strip system.
Altering with unfilled strips, know
Variations in Clear-felling System: The clear-felling can be done in various ways. The clear felling can be done in patches or in
strips. The strip may be alternate or progressive.
1. The clear strip system
2. The alternate strip systems
3. Clear felling in patches
4. Clear felling with advanced regeneration
5. Clear-felling with retention of sheltered
1. Patches 2. Alternate Strips
3. Progressive Strips
THE CLEAR-STRIP SYSTEM

A silvicultural system in which clear-felling is done in the form of strips which progress successively in one direction
across the regeneration area. It is also known as progressive strip system.
Pattern of felling - The clear-felled strips are separated by unfilled forest of sufficient width which may be multiple
width of clear-felled strip. The period after which can be felled depend on:
• when natural regeneration is relied upon, and
• the period for which protection against adverse factors is required.
Wind
CS IV CS III CS II Cutting Section I
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Arrangement of strips in progressive strip system
Method of regeneration
This system can be regenerated artificially as well as naturally depending on the
circumstances.
Character of the crop produced
The clear-strip system results in production of even-aged crop. Each strip can be treated as sub-compartment and can be
shown separately on the management map.
ADVANTAGES
This system has all the advantages of the CF system and additional, it does not deteriorate the site and maintains aesthetic
beauty of the area.
DISADVANTAGES
1) Protection of regeneration in strips is not only difficult but also costly.
2) In case of artificial regeneration, burning of felling refuse in the strips often results in fire spreading to the
un-felled forests.
APPLICATION
The oldest example is the working of Pinus kesia in Assam, India.
THE ALTERNATE-STRIP SYSTEM
The Alternate-strip system may be defined as a silvicultural system in which clearfelling is done in the form of strips, and
the clear-felled strips alternate with unfilled stips of similar width, though sometimes these may be narrower or wider
also.
Pattern of felling - The width of felled and unfilled strips varies place to place. Troup indicated the width of clear-felled
strips to be 36m to 56m altering with un-filled strips of similar width. Whereas, in France with clear-felled strips 40m-
50m, and the un-felled strips were only 15m-20m. The period after which the alternate un-felled strips are felled also
varies according to circumstances.

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Arrangement of felled and un-filled strips in alternate-strip system
Mode of regeneration
The initially felled strips are regenerated naturally, but the intervening unfilled strips may be naturally or artificially
depending on the circumstances.
Pattern of crop
The pattern of crop produced depends upon the period after which the alternate strips are felled and the rotation. The
alternate un-felled-strips not only supply seed for the felled strips but exercise protective influence on the regeneration of
the felled strips results in production of even-aged crop.
ADVANTAGES
1) This system has a definite advantage as it supplies seed to the felled strips from two sides.
2) This system has two distinct advantages, viz, lesser damage to seed bearers from wind and also young crop from
felling and extraction of the seed bearers.
3) While it affords complete overhead light for the natural regeneration of light demanders, it protects their
sensitive seedlings against frost and cold wind.
DISADVANTAGES
1) If the alignment of strips is at right angles in the hills, it creates serious problem for the extraction of timber,
when felled.
2) In our conditions, it does not afford any protection to regeneration of shsde bearing species.
3) Fire protection is very difficult.
APPLICATION
This system applied to Sal in Dehra Dun India with clear-felled strips 12m wide alternating with un-felled strips 36m.
Recently it has been successfully applied to Acacia mollissima in Tamil Nadu.

2.2 Seed Tree Method:
 In this method the stand is clear felled except for a few seed trees, which are left standing singly or in groups to produce
seeds for regeneration
 After a new crop is established these seed trees may be removed or left indefinitely.
 The chief distinction from shelter wood system is that the seed trees are retained only for seed production and not enough to
provide shelter.
On the basis of arrangements of seed trees the seed tree methods may be:
1. Single Tree Method: the seed trees are left scattered singly over the entire area.
2. Group Tree Method: the seed trees are left in groups scattered over the entire area
3. Strips or Rows Method: the seed trees are left in strips or in rows
Characteristic of Seed Trees:
1. Wind firmness: Trees with tapering boles are more resistant to wind.
2. Seed producing ability: The best trees are members of Dominant crown class having wide deep crowns and relatively large
live crown ratio.
3. Age: Seed tree must be old enough to produce abundant fertile seeds; the age at which seed bearing begins in closed stand is
the safest criteria.
Number and Distribution of Seed Trees: It depends on following factors:
1. Amount of seed produced/tree
2. The no. of seed required
3. Seed Dissemination
4. Number of viable seed produced (depend on pollination. There will be low no of viable seed in isolated trees
5. Seed germination
6. Seedling establishment
7. Risk of loss by wind of lightning
Advantage:
Ample opportunity for Phenotypic Selection, suitable for Light demanding species
Disadvantage:
Under stocking, over stocking, damage by forest and drought
Shelter wood Systems
1. Shelter wood system is a silvicultural systems in which the over wood is removed gradually in two or more successive felling
depending on the progress of regeneration.
2. In other words, the shelter wood system involves gradual removal of the entire stand in two or more successive felling
extending over a part of the rotation.
3. The trees, which are no longer capable of increment in value, are removed to make room for regeneration to come in
4. The trees, which are growing vigorously, are retained to provide
a. Shelter
b. Seed
c. Rapid diameter increment and value increment
d. Protection of site against deterioration.
Kinds of Shelter wood system:
The varying patterns of regeneration felling and their distribution in space and time, results in a variety of shelter wood systems
1. Uniform shelter wood system: Regeneration felling is done by making uniform opening
2. Group shelter wood system: Regeneration felling is done in scattered groups
3. The shelter wood strip system: Regeneration felling is done in strips
4. Irregular Shelter wood System: Opening is made irregularly. Uneven aged crop is produced There is a compromise between
shelter wood group system & selection system

5. Indian irregular shelter wood system: Uneven aged crop is produced and immature trees are retained as future crop. It is a
compromise between Uniform System and Selection System.
6. One cut sheltered: Removal of over wood in one operation if sufficient advance growth is present
Pattern of fellings:
1. Predatory fellings: It is felling made udder a high forest system with the object of creating conditions favorable to seed
production and natural regeneration.
2. Seedling felling: It is defined as opening the canopy of a mature stand to provide conditions securing regeneration from the
seed of trees retained. This is the first stage of regeneration felling.
3. Secondary felling: It is defined as a regeneration felling carried out between seeding felling carried out between seeding
fellings and final felling in order gradually to remove the shelter and admit increasing light to the regenerated crop.
4. Final felling: It is defined as the removal of the last shelter or seed trees after regeneration has been affected. It is the final
stage in regeneration felling.
2.3.1 Uniform Shelter wood System (Uniform System)
The canopy is uniformly opened up over the whole are of a compartment to obtain uniform regeneration. It is also called as shelter wood
compartment system or compartment system.
Pattern of felling:
1. Preparatory felling:
 It is a felling made under a high forest system with the object of creating conditions favorable to seed production and
natural regeneration
 Create gaps in the canopy
 Create favorable conditions on the forest floor.
2. Seeding felling:
 It is defined as opening the canopy of a mature stand to provide conditions securing regeneration from the seed of trees
retained
 This is the first stage of regeneration felling and the object is to make opening in the canopy all over the compartment so
that favorable conditions are created for regeneration.
 There are two important considerations:
1. Selection of trees to be retained:
a. Genetically superior trees
b. The number of trees varies according to the silvicultural requirement of species.
c. The shade bearing sp. and those with heavy seed-retain more seed trees (small opening)
d. The light demanding sp. and those with light seed-retain less seed trees (large opening)
e. For the same sp. opening is lighter in the drier areas than in moist areas.
f. Seeding felling is done with caution if there is danger of invasion of grasses and weeds.
g. Large no. of seed bearers on southern aspect and less no. of seed bearers on northern aspect for the same species.
2. The number of seed bearers: The number of seed bearers to be retained depends on:
a. Seed requirement of the area.
b. Amount of light to be admitted (shelter)
c. Moisture condition
d. Condition of weed growth
e. Altitude and aspect.
Examples:
Species No. of seed bearers Approx. distance
Pinus roxburghii 12-18 on cooler aspect 24-30m
20-25 on warmer aspect 20-22m
Pinus wallichiana 20-25 18-20m
Cedrus deodara (Deodar) 45-50 14-15m
Picea smithiana (Spruces)
Abies pindrow (Fir) 75-87 11-12m

Secondary felling:
It is defined as a regeneration felling carried out between seeding felling and final felling in order gradually to remove the shelter and
admit increasing light to the regenerated crop. Removal of trees in secondary felling depends on progress of regeneration and its light
requirement. It also helps in the manipulation of mixture of crop.
Final felling:
It is defined as the removal of the last shelter or seed trees after regeneration has been affected. It is the final stage in regeneration felling
when the are is completely stocked with established regeneration which do not require shelter.
Uniform Shelter wood system
Periodic Block:
It is necessary to divide the rotation period in to as many parts as the number by which the rotation is divisible by the time taken to
regenerate an area.
Example
 If the rotation is 120 years and it takes 30 years to regenerate the area naturally.
 The rotation will be divided into periods. As each of this part is felled and regenerated in a particular period, it is called a
periodic Block.
 120/30 = 4 periodic blocks
Age Class (Age of crop in years)
Period and at the beginning at the end
Periodic block of the period of periodRemarks
I 91-120 1-30 after one rotation
II 61-90 91-120
III 31-60 61-90
IV 1-30 31-60
Each area moves from one periodic block to other
Fig: Sequence of Movement of Forest in Various Periodic Blocks
Length of Regeneration Period: It Depends on:
1. Frequency of seed years
2. Light requirement.
3. Other climate factors
Periodic
block I
Periodic
block II
Per
Periodic
block III

4. Soil condition
5. Condition of grass and competing weed growth
6. Incidence of grazing, browsing, and
7. fire
Allotment of areas to Periodic Block
1. Permanent (Regeneration period is fixed)
FS x P (Number of years in the period)
Area of Periodic Block = -------------------------------------------
R (Rotation)
= 1000 x 30
------------- =250 ha.
a 120
b (a) Self contained
c (b) Scattered (is adapted in India)
2. Floating (Regeneration Period is not fixed)
(Simple Periodic Block)
FS x estimated regeneration period
= -------------------------------------------
Rotation
Area of the felling series
= ------------------------------
No. of periodic block
= 1000/4 or 1000/5
Using the example of 4 PBs, silvicultural operations to be carried out in various periodic blocks will be as follows:
No. of PB PBI PBII PBIII PBIV
Age of crops (years in the beginning
of period
91-120 61-90 31-60 1-30
Silvicultural operation
Regeneration
felling
Thinning if necessary preparatory felling
if prescribed
Thinning Cleaning,
thinning
Numbering of Periodic Block; I, II, III, IV
Advantages:
1. Marking and felling of trees of the over wood are simpler than in other shelter wood systems as well as selection system.
2. In this system the soil is not completely denuded so there is little risk of soil deterioration and erosion.
3. As the regeneration operations are carried out under the shelter of older crop, there is little danger of invasion of the area by weeds
and grasses.
4. The young crop is protected against adverse climatic factors such as cold, frost, winds, drought etc.
5. As the regeneration is obtained from seeds obtained from best selected trees, the new crop is superior.
6. It is a suitable system for the regeneration of both light demander and shade bearer species. In mixed forest it is suitable to
regenerate a mixture of different species by regulating of light reaching on forest floor.
7. As the new crop appears before the old one is harvested, the average length of rotation is shortened.
8. The growing space is more fully utilized as the regeneration grows under the shelter of older trees.
9. It makes supervision and control of various operations easy.
10. From aesthetic point of view the system is superior to clear felling system.
Disadvantages:
1. As the over wood is removed in more than one operation there is much damage to the young crop.
2. In mixed forest with species having different light requirement, the manipulation of canopy requires skill and knowledge of
silvicultural requirement of species composing the mixture.
3. The isolated seed bearers are susceptible to wind damage.
4. In the species having long intervals between seed years, after seeding felling there may be invasion by weeds and regeneration
may be affected.

5. In species with longer regeneration period, weeding and cleaning has to be done for longer period and the natural regeneration
becomes costly.
The Group System:
Regeneration felling is carried out in scattered groups either because of presence of advance growth or to induce regeneration de-nova
so that there foci of regeneration can be enlarged centrifugally to merge with each other ultimately.
DEFINITION
A silvicultural System in which regeneration fellings, instead of being done uniformly all over the compartment, are carried out in
scattered groups, either because the presence of advance growth in those groups, or to induce regeneration so that these foci of
regeneration can be enlarged centrifugally to mange with each other ultimately.
Thus, regeneration starts from some natural nuclei or groups of advance growth, or from artificially created nuclei, and spreads
centrifugally to finally cover the entire area.
First developed by Karl Gayer in Germany as a reaction against CF system, popularly known as Femelschalag.
Kind of cutting Areas marked
1 2 3 4
Preparatory and seed
cutting combined
5 10
Removal cutting 10 15
Final cutting 15 20
Figure 14-7: Arrangement of cutting in a stand regenerated by the group-shelter wood method. Advance reproduction was present
before cutting on areas marked 1.
PATTERN OF FELLINGS
 locate groups of promising advance growth
 all or some overwood is removed silviculturally necessary
 seeding felling is done on the periphery
 if the groups of advance growth are not adequate, some gaps are created by felling trees in small groups to enable
regeneration to come up in these gaps
 when regeneration appears in these artificially created gaps, secondary felling is done therein as well as in the seeding-felled
rings round natural foci
 when regeneration in these gaps is established, final fellings may be done
 Simultaneously, secondary fellings are done in the seeding-felled peripheral strips round then and fresh seeding fellings in
rings round them. In this way, the regeneration spreads centrifugally and cover the entire area. Blanks, if any are planted up.
Centrifugal sequence of fellings

Describing Figure
1. Advance growth / secondary felling will be done
2. Secondary felling in 1/ seeding felling in 2
3. Final felling in 1/ secondary felling in 2/ seeding felling in 3
4. Final felling in 2/ secondary felling in 3/ seeding felling in 4
5. Final felling in 3/ secondary felling in 4 / seeding felling in 5
6. Final felling in 4/ secondary felling in 5. Ultimately final felling will be done in area 5
Other considerations
 size of the gap and rings varies with species and their light requirements
 light demanders require bigger gaps and wider rings than shade bearers
 In mixed crops, depend upon the desire proportion between the light demanders and shade bearers
 gaps proceed against the direction of wind and only on leeward side to minimize the risk of wind damage
TENDING
Tending operation required are slash disposal after felling, followed by weeding and shrub-cutting, as and when necessary, after the
regeneration appears.
CHARACTER OF CROP PRODUCED
 Is not so even-aged as the crop in Uniform system because it is produced by a series of seeding fellings carried out in
successive concentric circular strips
 In early stages it looks fairly un-evenaged but towards the end it looks more or less even-aged
 If the regeneration period is long the crop becomes slightly un-evenaged, but recovers towards the end of rotation, the system
is accepted as even-aged system. Its canopy has a wavy profile, usually known as Gayer’s line.
Advantage:
1. The young crop develops in more natural way.
2. Adjoining trees protects the young regeneration.
3. Little danger of the seed bearers being uprooted by windstorm.
4. Less damage of young crop by regulating the fall of trees in unfelled areas.
Disadvantages:
1. Existing advanced growth has to be located which is difficult in hills.
2. Marking of seeding felling is difficult around group of advanced growth in hilly terrain.
3. The weeding and cleaning is difficult and costly.
4. As the work gets diffused its supervision and control becomes difficult.
5. Over extensive area, intensive working is not possible.
6. Requires individual attention of a single officer for about 30 years, which is not possible.
APPLICATION
 The group system first tried in HP, India for Deodar and Blue pine but it was not successful

 In Orrisa, India for Sal also failed because of heavy invasion of grass in groups and consequent accidental fires
 It was again tried in Chakrata, UP for Deodar but was given up due to:
– Groups of advance growth and artificially created gaps could not be mapped in practice because of difficult hilly
terrain
– Protection of regeneration against grazing and fire could not be enforced done
2. Shelter wood strip system:
Regeneration felling is done in the form of strips successively from one side of the compartment, progressing against the direction of
wind.
The width of the strip varies according to local conditions, and may vary from 20 m to 30 or even more.
Shelter wood Strip System
Advantage:
a. It provides protection from wind.
Disadvantage:
a. Lying out of strips, execution of felling, logging, transport of material, tending, protection against grazing and fire is difficult
and not applied in India.
3. The Irregular Shelter wood System:
Regeneration felling is on the pattern of group system but as the regeneration period is long, the crop produced is uneven aged or
irregular. This is a compromise between shelter wood group system and selection system.
4. Indian Irregular Sheltered System:
Silvicultural System is which the crop to be regenerated is open up irregularly and the resultant crop is uneven aged, a compromise
between uniform system and selection system.
1. It provides for retention of groups of well-grown poles and immature trees (up to 40 cm. diameters) as the future crop.
2. It permits the adoption of selection felling on steep and rugged portion of compartment being worked under uniform system.
Irregular Shelter wood methods
The Selection System:
The selection system is defined as a silvicultural system in which felling and regeneration are distributed over the whole of the area and the
resultant crop is so uneven-aged that trees of all ages are found mixed together over every part of the area. Such a crop is referred to as
selection forest or all-aged forest. The selection system may be of following two types.

1. Single tree selection
2. Group selection
Felling of trees all over the area of a forest is possible when the area is small but if the area is large it is not possible to fell the trees over the
entire area annually. Therefore, the area to be worked under selection system is divided in to coups and felling is confined to one coup every
year.
1. Ideal selection system
2. Periodic selection system
1. Ideal selection Systems:
When fellings are carried out over the whole area each year. Felling of trees all over the area of a forest is possible when the area is
small.
2. Periodic selection system:
When fellings are carried out over only a part of the forest each year under a felling cycle. If the area is larger it is not possible to fell
the trees over the entire area annually. Therefore, the area to be worked under selection system is divided in to coupes and felling is
confined to one coupe every year. Thus, felling is done in a coupe after a certain number of years, which is equal to the number of
coupes. This interval is known as felling cycle, which is defined as the time between two successive main felling on the same area. The
length of the felling cycle affects the silvilcultural of species, exploitation of forest, and the nature of crop produced.
Pattern of felling:
1. Single Tree Selection: When the trees are felled singly
2. Group Selection: When the trees are felled in groups
3. Strip Selection: When the trees are felled in strips.
Thus, felling is done in a coup after a certain number of years, which is equal to the number of coups. This interval is known as felling cycle,
which is defined as the time between two successive main felling on the same area. The length of the felling cycle affects the silviculture of
species, exploitation of forest, and the nature of crop produced.
Selection forest or all aged forest:
1. The felling and regeneration are distributed over the whole area.
2. Uneven aged - All aged.
3. Regeneration operations are carried out throughout the life of crop.
Conduct of felling: following categories of trees are generally removed.
(1) Dead, dying, diseased, misshapen or otherwise defective trees interfering with the growth of better trees.
(2) Trees of undesirable species
(3) Immature trees, which can be removed in judicious thinning, carried out in different age classes.
(4) Mature tree of and above the exploitable diameter which will leave gaps for regeneration to come in
(5) Maintain proper proportion of diameter classes – Maintain reveres ‘J ‘shaped curve.
Consideration for Application:
1. Topography
2. Catchment Areas
3. Communication
4. Market Requirement
5. Silvicultural Considerations

Advantages:
1. It results in the production of all aged forest. Trees of all ages are mixed together on each unit of area. Then the growing space and
site factors are fully utilized.
2. By maintaining continuous leaf cover, the selection systems conserve soil and moisture to the fullest extent possible.
3. The selection forest produced is most resistant to injuries by insect pests and adverse climate factors.
4. It prevents invasion of grass and weeds.
5. Natural regeneration comes up without difficulty due to abundance of seed bearers, use of every seed year and the protection
afforded to seedlings.
6. The forest regenerates itself continuously, without any time limit.
7. As the lower age class trees grow below the older trees, the selection system results in producing more growing stock in large size
trees per unit area than the uniform system.
8. This is best system of producing large size trees.
9. It produces a forest which is superior biologically (Bio-diversity) as well as in its aesthetic and scenic value.
Disadvantages:
1. Considerable skill is required in carrying out marking and felling to ensure regeneration to come up in the gaps. This requires
knowledge of silviculture of species.
2. As the mature trees to be removed are scattered, cost of logging and extraction is high.
3. Felling, logging and extraction causes’ damage to the young crop.
4. Seed is obtained from good as well as bad trees; there is genetic deterioration of future crop.
5. There is much damage to regeneration by grazing.
6. As the area is extensive, strict fire protection is difficult. Thus accidental fires result in damaging the new crop.
7. Success or failure of regeneration is difficult to assess.
8. In a mixed crop with lower % of valuable species, when valuable sp. are removed there vacancies are filled up by less valuable
species.
9. Maintaining proper proportion of each diameter classes is very difficult and there will be Misconception of Reverse J shaped
curve.
10. It is difficult to know exact growing stock, normal distribution of tree sp. and DBH.
11. Heavy felling.
Accessory systems
Accessory systems are those high forest systems, which originate from other even aged systems by modification of techniques,
resulting in an irregular or two-storeyed high forest. The following accessory systems are commonly met with.
1. Two storeyed high forest system
2. High forest with reserves system
3. Improvement felling
1. Two storeyed high forest system:
It is silvicultural system in which results in the formation of a two storeyed forest in which the canopy can be differentiated in to two
strata, in each of which the dominant species is usually different. The crop in each storey is approximately even-aged, and is of seedling
origin. The lower story may be obtained by natural regeneration by seed brought from outside, but usually by under-planting, which is
done for one of the following objects.
or usually by enrichment planting for one of the following object.
1. For protection of soil
2. For increasing the proportion of valuable sp. (Enrichment planting)
3. For propagation of species, which cannot be raised in the open?
Advantage:
Two storeyed high forests may be adopted for any of the following reasons.
1. To protect soil with the lower storey when the upper storey is incapable of doing so.
2. To increase production by growing two crops on the same land.
3. To propagate shade bearing sp. or frost tender sp.
4. To change the species gradually.
5. To provide for a vertical mixture in sp. composition.
6. To obtain early return.

Disadvantage
1. Under-planting is a difficult operations and unless done carefully , it is likely to fail
2. The under storey crop may affect the growth of upper storey crop.
3. The under-storey is likely to be damaged during thinning or felling in the upper storey crop.
Application
 Chirpine and Sal forest, where Sal grows under Chirpine
 Deodar grows under pure crop of Chirpine
 Oaks growing under Deodar and Chirpine crops.
 Introducing teak in Sal areas
 Introducing Sissoo in Sal areas
 Planting Mulberry under Sissoo
High Forest with reserves system:
In this system selected trees of the crop being regenerated are retained for part or whole of the second rotation, in order to produce large
size timber i.e.
 Clear felling system with reservation
 Reservation of some trees during final felling in uniform sheltered system.
Improvement felling (TSI):
It is not a silvicultural system as it neither aims at regenerating the crop, nor producing a crop of distinctive characteristics. It is defined
as the removal of inferior growing stock in the interest of better growth of more valuable individuals. It is usually applied to mixed
uneven-aged forest. The following operations are usually done in improvement felling.
1. Felling of dead, dying, and diseased (3Ds) trees.
2. Felling of saleable unsound over mature trees which are not likely to survive up to the nest felling, provided these are not required
for protection.
3. Felling of unsalable over mature trees, if their removal benefits the other trees or regeneration.
4. Feelings of unsound or badly shaped mature or immature trees, if it benefits other trees. But it should not be revenue filling.
5. Thinning of congested groups of trees and poles likely to benefit from the operation.
6. Removal of badly shaped and damaged saplings and advance growth expected to give better coppice shoot
7. Removal of undesirable undergrowth or trees of inferior species. Which are preventing or likely to prevent development of
regeneration of the desired species?
8. Climber cutting
B. Coppice Systems
The silvicultural system in which the crop is regenerated mainly from stool coppice and with short rotation. Reproduction is obtained
from the shoots arising from the adventitious buds of the stump of felled trees.
Types of coppice system:
On the basis of pattern of felling the coppice system is of various types.
1. Simple coppice system.
2. The coppice of two rotation system.
3. The shelter wood coppice system.
4. The coppice with standard system.
5. The coppice with Reserve System.
6. Coppice Selection System.
7. Pollarding
Factors affecting natural regeneration by coppice:
1. Species- coppicing power.
2. Age of tree-pole and young trees.
3. Season of coppicing-before spring.
4. Height of stump-15-25 cm.
5. Rotation-short.

6. Silvicultural system-clear-felling.
1. Simple coppice system:
The simple coppice system is defined as a silvicultural system based on stool coppice in which the old crop is clear felled completely
with no reservation.
Patter of felling in simple coppice system consists in clear felling a fixed area annually.
Area of coppice coupe = 1/n x total area. Where n is the number of years in rotation.
Season for coppicing:
1. The best season for coppicing is a little before the growth start in spring because at this time there is a large reserve food material
in roots which is utilized by the coppice shoots.
2. During the dormancy period. (from Nov. – Feb./March)
Method of felling:
1. The stump should neither be too low/high.
2. The lower the stump, the better it is for coppice shoot.
3. But if the trees are cut very low there is a danger of the stump splitting and or drying up from top.
4. On the other hand, the higher the stumps, the greater the possibility of shoots being damaged by wind or animals.
5. Stumps are usually kept, 15-25 cm high. (10 cm for eucalyptus)
Figure: Simple Coppice System:
Precaution during felling:
1. Stump should not split during felling trees.
2. The bark did not get detach from the wood.
3. Stump should slope slightly in one direction.
Tending:
Cleaning is done to remove climbers and inferior sp. and to reduce the no. of shoots to two or three.
Thinning if necessary is carried out in fifth year and the no. of shoot is reduced to one/stool. This is called as singling out operation for
pole or timber.
Advantage:
1. The system is very simple and does not require any skill in making.
2. The regeneration is more certain.

3. As coppice shoot grow faster in the beginning the cost of weeding, cleaning and protection is much less than in case of
reproduction by seed.
4. The mean annual increment (MAI) of the coppice crop is much higher then that obtained under high forest.
5. The net returns on investment are relatively higher primarily due to short rotation and less investment.
6. Although it is shortsighted system but very suitable for producing fuel wood and small sized timber to fulfill the immediate need
of the society.
Disadvantage:
1. The system tends to exhaust mineral substances in the soil.
2. This system is not permanent because the trees cannot keep on coppicing indefinitely.
3. The coppice crop is liable to great damage by frost and wind.
4. This is not a very desirable system from aesthetic point of view.
5. Risk of site deterioration (Soil erosion, weed invasion etc.)
2. Coppice with standards system
It is silvicultural system based on coppice in which over wood of standards, usually of seedling origin and composed of trees of various
ages, is kept over coppice for a period of multiple coppice rotation and as a permanent feature of the crop throughout its life.
Purpose of standards:
1. Supply of large size timber
2. Protection against frost
3. Enrichment of coppice
4. To provide seedling regeneration
5. Increase in revenue
Thus, 1) Constitution of crop: lower storey (even aged coppice crop), upper storey (over Wood of standards).
2) Rotation: two rotations- one for coppice and one for standard (multiple of coppice rotation).
Pattern of felling: All trees except standards are clear felled and selection of standards depends on
1. Species: The species of same or different sp. or a mixture of species.
2. Characteristics and quality of standards: Standards should be as follow
1. Most valuable species
2. long, clean bole with light foliage
3. capable of putting on increment and increasing in value
4. wind firm
5. light demanders
3. No. of standards: Number of standards depend on following
1. Object of mgt.
2. Climatic factors (frost)
3. Silvicultural characteristics of species (light, frost etc.)
 Standards should not occupy more than one third of the canopy (33%)
 The space allotted to the standards is to be properly distributed amongst the various age classes.
4. Distribution of standards: Uniformly distributed over the whole area.
If .3% of canopy area is occupied by standards and there are three age class present than each age class will occupy 0.1% of canopy
area. It means more no. of trees of lower age class.
Advantages:
1. There is greater protection to the soil.
2. Advantage of heavy shelter wood felling and selection system.

3. Standards serve as seed bearers and provide seed.
4. The investment is small and the net return is higher.
5. Aesthetically superior than simple coppice.
Disadvantage:
1. It requires great skill in maintaining correct balance between standards and coppice and between standards of different age classes.
2. This is a combination of simple coppice system and high forest system with the advantage of none.
3. It has an exhaustive effect on soil.
4. Felling and extraction cost is higher than high forest system.
Conditions of Application of CWS:
1. Where there is demand of firewood, pole, and timber.
2. Where simple coppice is inhibited due to climatic factors and silvicultural characteristics of species.
C.W. S. Not suitable for:
1. If required no. of standards of desired species are not available.
2. Poles of valuable species have to be coppiced immaturely which can produce large timber if thinning is done.
3. It does not provide for retention of other trees for economic, silvicultural or protective consideration, howsoever important and
necessary these may be.
Example:
Forest Coppice rotation Standard rotation
1. Sal 30 years 60 years
2. Jamun belt 20 or 30 40 or 60
3. Dry deciduous forest 30 90
4. Anogeissus pendula 40 80
3. The coppice with Reserves System
A silvicultural system in which felling is done only in suitable areas likely to benefit, after reserving all financially immature growth of
principal as well as other valuable miscellaneous species, either singly or in optimally spaced groups, trees yielding products of and
first introduced in 1934-35. The tenth silvicultural conference held in 1961 recognized it as a definite silvicultural system and
recommended its application to dry deciduous forest extensively.
Pattern of felling:
In this system, the emphasis is not on felling but on conservation. Distinguish areas which, require protection or some improvement
felling and areas in which felling can be done according to the requirement of crop, local people, and site. Then felling may be from
clear felling to practically no felling by reserving all trees.
1. Reservation by Area:
a) Under stocked areas where felling is likely to retard the process of rehabilitation by nature.
b) Eroded areas or areas liable to erosion, strips of land along streams for soil conservation.
c) Area around springs wells, camping sites and places of worship.
d) Areas having dense pole crop
e) High quality areas in which the crop is in its optimum condition. In such areas light improvement felling can be done if
necessary.
2. Reservation by trees: Reservation of individual trees up to a fixed girth class which is generally between 60-75 cm. with the
following objectives:
1. Reservation of miscellaneous sp. for maintaining healthy mixture of species.
2. All advanced growth of valuable species up to 24 cm. dbh. Is reserved.
3. Reservation for completing the stocking and supply of seed.
The rest of the crop is felled. The basic principle is the removal of all growth that has become financially mature unless its retention is
required for protection of soil, maintenance of its fertility, for supply of seed, fruit or any other forest produce required by the local
population, for supply of industrial timber and for meeting the requirement of Lac industry.
Mode of Regeneration:

Regeneration is generally obtained by coppice but advance growth and regeneration from seed also make substantial contribution to it.
Tending:
Tending should be done-clearing, climber cutting, and reduction of coppice shoots. Recently rotation has been discarded and suggested
to work the forests on felling cycle of 10-15 years.
Character of the crop:
The resultant crop under this system comprises of irregular groups of even aged coppice with uneven aged reserve crop scattered
irregularly. Thus taking the crop as whole, it is uneven aged.
Advantage:
1. It helps in improving the quality of locality as a result of soil and moisture conservation, maintenance of crop mixture.
2. It helps in improving the condition and composition of crop.
3. It fulfills the needs of local population and the requirement of industries.
4. It avoids the sacrifice of financially immature crop whose value increases. Thus it offers best financial returns per unit area.
Disadvantage:
1. Its execution requires a high degree of skill.
2. Reservation of a large number of trees affects coppice growth adversely
Conditions of applicability:
1. When the crop varies greatly in density, composition, and quality and proportion of valuable species is low.
2. When most of the species are good coppicers and the coppicing power of most valuable species is vigorous.
3. When valuable species in the crop is light demanders.
Coppice with reserves system is not suitable:
1. When valuable species are shade bears and forest tenders.
2. When there is likelihood of invasion of fast growing obnoxious weeds, shrubs, and grasses such as Lantana, and Imperata.
3. When the crop does not contain valuable species and there is no hope to improving it by coppicing.
4. When it is not possible to protect the area against fire and grazing at least for five years after main felling.
2.7 Conservation
Conversions
Conversion is defined as a change from one silvicultural system or one (set of) species to another. Thus the concept of conversion
involves a change in crop composition and/or silvicultural system by which the crop are regenerated and replaced by the new crops of
distinctive form.
Change in crop composition: It is often necessitated from any of the following reasons.
1. Increasing yield from forest: Pine plantation in hills, Eucalyptus plantation in Sagarnath, Sissoo plantation in Kohalpur and in other
in degraded Sal forest enrichment planting
2. To meet the demand of industry: Populus, Eucalyptus, Acacia, Bombax, Teak
 The demand of industrial timber is fast increasing in our country, partly due to increasing population and partly general rise
in its standard of living.
 Thus, meeting these demand, it is necessary to raise species which meet the requirement of industry and, if the local forests
are do not have those species, new species suitable for the locality have to be introduced in those forests.
B. Change in the Silvicultural System:

Change from one silvicultural system to other is mainly for changing the character of the crop and/or for changing the method of
obtaining regeneration. A change in silvicultural system is due to following:
1. Advantage of a Particular System:
 When a particular silvicultural system known to offer greater advantages in terms of higher yield, simplicity of working,
concentration of work and improvement of the growing stock, it is usually adopted.
 This has been a very great consideration while making changes in the silvicultural systems.
 Conversion to uniform without appreciating the silvicultural requirements of the native species.
 Selection or selection cum improvement felling replaced by Uniform System.
 C.W.S. or Selection System replaced by C.W.R.
2. Failure of an Existing System:
 When a silvicultural system applied do a species fails to regenerate it, it has to be changed.
 When attempts to apply Uniform system to sal in Haldwani, UP failed, the conversion to uniform was given up and Indian
irregular shelter wood system adopted instead.
 In case of teak, clear-felling followed by natural or artificial regeneration is usually adopted
 Uniform System to Sal in Haldwani failed and Indian irregular shelter wood system was adopted.
 Uniform System to Deodar in Chakrata failed and Indian irregular shelter wood system was adopted.
 In case of Fir and Spruce uniform system was changed to Selection System or clear felling with reservation followed by
artificial regeneration.
 In case of Teak uniform system was changed to clear felling followed by natural or artificial regeneration.
3. Advances in Silvicultural knowledge and perfection of regeneration techniques:
 With continued research and practices, a lot of knowledge about the silviculture of species has been collected and, in some
cases, the technique of regeneration of species by natural and /or artificial means has been perfected.
 As a result of this:
1. Conversion to Uniform: By clear-felling followed by natural regeneration by seedling coppice as in Saranda (Bihar),
South Raipur (M.P) for Sal, North Betul(M.P)for Teak Taungia for Sal and Teak, in parts of UP, West Bengal, MP,
Maharastra and Kerala.
2. Indian Irregular Shelter wood System is usually applied in case of evergreens in Andaman and Arunachal Pardesh.
4. Development of communication and increase in market demand:
 With the development of communications and increase in market demand even for smaller sizes of timber, systems based on
concentrated regeneration are replacing the old systems.
 Continual evolution of silvicultural system…?
 Selective felling or selection cum improvement changed to concentrated regeneration.
1. Regeneration techniques have been perfected: Conversion to uniform by clear felling
2. Where regeneration is not assured, conversion to less irregular, Indian Irregular Shelter wood System
3. Where the site is poor, conversion to an elastic and composite technique, CWR based on coppice and seedlings,
resulting irregular crop.
Techniques of Conversion:
When a change in silvicultural system is desired the entire area is not subjected to conversion at a time. Only a part of the forest is
taken up under new system and rest is worked under old system where new areas are taken for conversion after completing conversion
in the areas taken previously.

 Not subjected to conversion at a time
 Only a part of the forest is taken up for the work during the plan period
 Rest of the area continuous to be worked under the old system
Example: Irregular forest worked under selection is to be subjected to conversion to uniform by clear-felling followed by artificial
regeneration, and the rest is worked under selection system.
The converted crop is transferred to the last PB more areas to PB I for clear-felling and planting, while remaining area worked under
selection. Thus, 3PBs as: PB-I for areas to be converted, PB-II un allotted for areas to be worked under selection and PB-III for
converted crop which is only tended by thinning.
Pace or speed of conversion:
The conversion period means the period in which conversion is to be done. The conversion period is very important consideration.
When the conversion period is short the conversion proceeds with a fast speed on the other hand if conversion period is long, the
conversion is slow.
The following considerations affect the decision about the length of conversion period:
1. Sacrifice of immature crop: The sacrifice is greater when the period is shorter and lesser when it is longer.
2. Proportion of the over mature growing stock with negative increment.
a. Larger the proportion of over mature trees the conversion period should be short.
b. Lesser ,, ,, ,, ,, ,, long.
3. Hiatus between the age of first converted crop and the exploitable age at the end of conversion period:
 The decision on the length of conversion period should also take into account the age of first converted crop at the end of
conversion period and compare it with exploitable age.
 If the age of first converted crop is less than the exploitable age there will be a hiatus at the end of conversion felling till the
start of felling under the new system (uniform system).
 Thus, the shorter the conversion period, the greater the hiatus. To overcome this difficulty following two alternatives can be
adopted.
1. The conversion period should be so fixed, that the first converted crop is mature at the end of conversion period.
2. Part of the young immature crop should be retained as part of the future crop. These increases the mean age of converted
crop and makes it fit for exploitation earlier.
Examples of Conversion:
Conversion to uniform by clear felling with natural regeneration and clear felling with artificial regeneration
Approx. Area = Area of Working circle x Working Plan Period
Conversion Period
PB1 allotted.
PBII unallotted.
PBIII converted or last PB.
1. Conversion to relatively less irregular crop by retaining young poles up to 20-30 cm. Diameter in clear felling.
2. Conversion from CWS to CWR (Dry deciduous forest of MP, 1935 larger scale). The area of working circle divided into
three categories.
3. Conversion of coppice and CWS to high forest.
A. Conversion by natural regeneration (to retain the existing BL species)
a. Conversion of CWS to uniform broad-leafed high forest (by uniform).
b. .,, ,, ,, irregular ,, ,, ,,(by selection)
c. .,, ,, ,, coniferous high forest (in case of fir).
B. Conversion by artificial regeneration (To change sp. from BL- conifer)
a. Artificial conversion by clear felling.
b. Artificial conversion under a sheltered (fir).
c. Artificial conversion by groups (spruce).

I. Conversion to uniform
– Area approximation of the working circle as; working plan period divided by the conversion period is selected for
conversion during a WP period
– Clear-felled in coupes, nearly equal area with nearly equi-productiveness
– Natural regeneration due to advance growth
– Some overwood is left in absence of advance growth
– Advance growth is cut back and brunt
– Planted up polypots and cutting if needed
– Tended and no of coppice reduced 1or2 in yr5
– Partly under treatment as PB-I , rest under PB-un allotted, and the converted crop as last or PB-III
Examples: Teak and Sal in MP, India
II. Conversion to relatively less irregular crop:
– When regeneration cannot be assured in above situation, it is not possible to adopt conversion.
– In such cases, it is usual to retain young poles, upto 20 or 30cm diameter to complete the regeneration in short
period so that uniform system could be applied at the end of conversion
– Though retention of young poles makes the resultant crop irregular yet it is only way out of the problem created by
failure of regeneration, when and where desired reasonably short time, or vulnerability to damage from various
factors, climatic or biotic.
Examples: Sal forest in Raipur division Dehra Dun, India has Conversion to uniform as the Indian Irregular Shelterwood System.
III. Conversion from CWS to CWR:
This type of conversion has been initiated on the realisation of deficiencies of CWS system. During conversion the area of the working
circle was differentiated into:
i. In which CWR would be applied during the current plan period- (Marking)
ii. In which CWR would be applied during the future working plans,-(no work) and
iii. In which CWR had already been applied –(only tending work)
Form of conversion
A. Mainly by natural regeneration to retain the existing broad-leaved species; and
B. By artificial regeneration to change the composition from broad-leaved to coniferous species.
A. Conversion by natural regeneration
i. Conversion of CWS to uniform broad-leaved high forest
• with a preparatory period of rest
• working circle is divided into a number of PBs, keeping in view the rotation and PB for regeneration
If rotation is 100 years and the regeneration period is 25 yrs, 4 PBs are distinguished
i. PB-I -maximum standards and seed bearers, over matured standards are removed, preparatory period of rest,
regeneration fellings
ii. PB-II -similar work as in PBI for 25 yrs
iii. PB-III -similar work as in PBI for 25 yrs till the entire crop is converted and uniform crop of 4 different age-class
is formed.
Method of intensive reservation
As a modification of the Conversion of CWS
It involved
i. Heavy conversion thinning in coppice crop to reduce the number and increase vigor
ii. Removal of physically over matured trees standing over seedlings or coppice crops, while retaining such standards as
a) Require to complete the stocking with seed
b) Are fit to form part of new crop, followed by immediate artificial regeneration of the coupe by sowing.
These forests are now worked under the Punjab Shelter wood System.
11 Conversion of CWS to irregular broad-leaved high forest by selection
 The crop is worked on a short felling cycle
 At each felling, dead, dying, badly-shaped and undesirable stems are removed

 The standards are opened out and coppice thinned to help existing seedlings and to provide enough light for natural
regeneration to come in
 a selection forest by group is developed
Advantages: Conversion proceeds steadily with a fairly constant yield from the beginning in the absence of period of rest and
advantage is taken of sporadic seeding
111 Conversion to CWS to coniferous high forest
If broadleaved forests worked under CWS are invaded by natural seedlings of silver fir, such forests are gradually converted by
carrying out cleanings in favour of fir
B. Conversion by artificial regeneration
i. Artificial conversion by clear felling
This involves complete clear-felling of coppice crop followed by artificial regeneration and is thus similar to such
work done in high forests. However, a great danger of artificially raised plants being suppressed by coppice
shoots. This method is more suited to poorer areas where the coppice growth is poor.
Artificial regeneration is effected, as a rule, by and not by sowing so that the plant may be out of danger of suppression by coppice
sooner.
ii. Artificial conversion under a shelter wood
The usual method is to allow the coppice to grow up to the time the crop is opened up for seeding felling. In the gaps so
created, silver fir is shown in patches.
The cover under which this species is introduced should not be too heavy and should be well above the ground.
Natural regeneration of beech, if any, is retained to form a mixture.
The over wood is gradually removed and the conifer is regularly tended.
iii. Felling is done in groups
By removing standards and thinning coppice, and moderately shade bearing species like spruce are introduced in gaps which are
gradually enlarged.
This method is adopted in places exposed to high winds.
Unit-3
Choice and formulation of silvilcultural systems
3.1 Factors to be considered while selecting and formulating a system
3.1.1 Identification of objectives of management
3.1.2 Provision for regeneration
3.1.3 Efficient use of growing agencies
3.1.4 Provision for sustained yield
3.1.5 Control of damaging agencies
3.1.6 Optimum use of forest capital
Introduction:
 A good silvicultural system is a long-term program of treatment designed to fit a specific set of circumstances
 It is not likely to be something that has already been invented and can simply be selected from schematic description of
silvicultural systems given in books
 In fact there is no cookbook for the application of silvicultural systems. A silvicultural system evolves over time as
circumstance change and knowledge of them improves.
 Formulation of a silvicultural system should start with the analysis of the natural and socioeconomic factors of the situation
 A solution is the devised to go as far as possible in capitalizing on the opportunities and conquering the difficulties found to exist.
 When the important act of inventing the solution has preceded far enough the less important step of attaching a name to it can be
taken.
 The standard terminology should be used in terms of meaningful to all foresters.
 If silvicultural systems are not chosen readymade from a manual or book, it is logical to examine the various considerations that
enter in to their construction and evolutionary development
 In the first place, a rational silvicultural system for a particular stand should fit logically in to the overall management plan for the
forest of which the stand is a part
 Second, it should represent the best possible amalgam of attempts to satisfy all the following major considerations.

Considerations:
1. Harmony with goals and characteristics of ownership
2. Provision for regeneration
3. Efficient use of growing space and site productivity
4. Control of damaging agencies
5. Provision for sustained yield
6. Optimum use of capital and growing stock
7. Concentration and efficient arrangements of operations
8. Resolution of conflicting objectives
1. Harmony with goals and characteristics of ownership:
 Choice among all the alternatives of silvicultural treatments is greatly simplified by clarification of the objectives of
ownership
 This logical first step automatically eliminates many of the possible alternatives.
 It is commonly necessary to help owners select their own objectives before thinking much about formulating a silvicultural
program.
 However, choices of objectives considered by owners must be limited to those that are reasonably attainable.
 The objective of ownership clearly dictate the relative amounts of attention paid to management for timber, fuel wood,
wildlife, forage, water and soil conservation, recreation, scenery or other benefits that forest may provide.
 Analysis of the objectives of ownership will normally define the kind of vegetation to be maintained, the kind of trees that are
to be grown, and the amount of time, money, and care that can be devoted to the process.
2. Provision for regeneration:
 Continuity of any forestry enterprises, ultimately and absolutely depends on replacing old trees with new.
 The objective of regenerating stands is seldom achieved without temporary, resolute, sacrifice of some other objectives.
 It is necessary to reduce the competition from the older vegetation enough to provide sufficient growing space for the new
crop.
 This often requires cutting some trees before they are mature or reserving others beyond the time of maturity as sources of
seed or shelter for the new crop.
 Only that system should be adapted which suits silvicultural requirement of the principal species to be regenerated.
 The most important factors, which should be considered, are light requirement, seeding, and the ease of regeneration.
 Considering the silvicultural requirement of the principal species and the owner’s objective of management any one of the
suitable methods of regeneration can be adopted.
3. Efficient use of growing space and site productivity:
 Forest vegetation usually seems to fill all of the available growing space but not all plants growing are equally efficient or
desirable.
 One important goal of managing a forestland is, to see that all available growing space is filled with useful plants.
 The most serious loss of potential production occurs during any interval of time that elapses between the removal of previous
crop and the establishment of new one. The ideal way to reduce such los of production and to retain some command of the
growing space is to start the new stand under the old one.
 It may be noted that at the time of regeneration, perfect efficiency could be achieved. If the new stand arrived at full
occupancy with just that number of trees that could ultimately be used profitably without any growing space having been
wasted during the transition from the old stand to the new.
 During the rotation increased efficiency in the use of growing space can be sought by application of intermediate cuttings,
including thinning and techniques of adjusting stand composition.
 Maximum efficiency in use of growing space is more likely to be achieved with mixed or uneven-aged than with pure and
even-aged stands.
General
• not all of the plants that are equally efficient or desirable
• what plants are desirable depends on
• objectives of ownership
• sometimes grasses or shrubs may be fully as desirable trees
• among tree species not all equally productive or adaptable to given site
As we know, silvicultural system is, among other things, program for the allocation of use of growing space throughout the whole
rotation
• see that all available growing space is filled with useful plants
• areas not occupied are an economic burden and may also invite invasion or undesirable competitive vegetation
• better to have a poor but useful plant than by useless or undesirable one

• full occupancy should not lead that stands become overcrowded with desirable trees
How it will be attained?
• What may initially appear to be understocking may correct itself as the trees of increases in size; overstocking may correct
itself automatically
• Damaging agencies may thin out overcrowded stands but only in unreliable fashion; pre-commercial thinning is a better
solution but it can be costly one
Observations:
• overstocking can be just inefficient as understocking
• to guard against either extreme is to develop and follow logical programs for regulations of stand density at all stages of
development from regeneration to maturity
• regeneration techniques that produce the most seedlings are not always the best
• a stand that has no obvious gaps does not maintain full occupancy of the growing space or use it with equal efficiency
throughout its life
• the times when it does not are mostly likely to come when it is young and when it is old
• biological productivity of a stand is highest at some period intermediate between youth and middle age
• optimum economic productivity is achieved somewhat latter because of the the effect of tree size on the utility of wood,
however, the annual productivity increases rapidly during youth and decline gradually with the onset of old age
Decline in production in latter stages is caused by:
• Decreasing biological efficiency
• slow destruction by damaging agencies
• Crown friction induced by increasing winds way reduces the amount of stand foliage even while the amount of meristematic
tissue to be nourished increases
• Margin between gross production and losses due to respiration and damage shrinks and a given classes of trees slowly losses
its command of the growing space
• Determining logical lengths and simply replacing mature stands at right time
How do we know?
• Biological efficiency is attainable as the root system and live crowns of the trees have expanded both horizontally and
vertically to occupy all the spaces they are capable of claiming
• Presence and vigour of shrubs and other vegetation can indicate the extent to which such stands short of full
occupancy
• Most serious loss occurs during any interval of time that elapses between the removal of the previous crop and the
establishment of new one
Overcoming the loss
• Start the new stand under the old one as with shelterwood cutting
• Advantageous with species that grow slowly in youths
• Securing the promptest possible regeneration after removal of the old stand
 Sprouting species-by coppice cutting
 Clear felling and planting provide prompt regeneration
Some losses is almost inevitable during the regeneration
Thus, not replacing stands any more often than is truly necessary
• Determine rotation length from calculations form present net worth for periods that extend over two or three
rotations rather than just one.
• Predicted effects not only of delays but also the gain from telescoping rotations that results when new stands are
started under old ones
• At the time of regeneration, perfect efficiency would be achieved if the new stand arrive at full occupancy with just
that number of trees that could ultimately be used profitably
• During the rotation increased efficiency in the use of growing space can be required by:
• Intermediate cuttings, including thinning and
• Techniques of adjusting stand composition
• By such measures that silvicultural treatment usually make contribution to increasing the yield over that naturally
available without treatment.
Other variables overcoming the loss:
• soil and site conditions often dictate some variation in species composition from one part of a stand to another
• sites where many species can grow and least true of those limiting moisture conditions that restrict the species
composition
• if a single species is best for all parts of a large tract of land, there may be enough site variation to call for differences
in rotation length in different places
For these reasons, maximum efficiency in use of growing space is more likely to be achieved with mixed or uneven-aged than
with pure or even-aged stands
Thus, the considerations depends on:

• Judgement about the relative cost and value of simplicity of uniformity and the fine-tuning possible with irregularity
Fitting of species to sites is not merely a matter of choice according to gross productivity but also strongly affected by ability to
survive and withstand damage
• many silvicultural system, especially those that involve felling a number of times during a rotation, contain important
provisions for some reduction of the enormous loss and waste.
• but also subtle losses of growth from excessive competition of poor trees with better ones
• It is logical to attempt to reduce this loss by measures such as frequent cutting, thinning, salvage cutting, and
integration of harvesting operations for multiple product utilization
Concluding efficient use of growing space and site productivity
• Cost of reducing waste and loss as well as that of capturing more complete occupancy of the site must always be
weightaged against the cost of additional effort involved
• Point of diminishing returns is reached long before if we start through the forest planting up every vacant gap,
salvaging every dying tree, thinning every stand, and utilizing every crooked top log.
4. Control of damaging agencies:
 Any successful silvicultural system is modified by the objective of creating stands with adequate resistance to insects,
pathogens, fire, wind or other injurious biotic or abiotic agencies.
 The modification is specific steps taken against specific damaging agencies and cannot be safely based on generalization.
 Most of the generalizations about the damaging agencies of the forest are more nearly true than falls, but they cannot be
accepted as a basis for silvicultural procedure without being scrutinized for applicability in each instance.
 Among these is the view that vigorous, fast growing trees are more resistant than less thrifty, slow growing ones; that mixed
stands are safer than pure, that uneven-aged stands are more resistant than even-aged, and that close duplication of natural
conditions will safeguard against many difficulties. Expectations are numerous.
5. Provision for sustain Yield:
 Perhaps the most noble and ambitious goal of forestry is that of making each forest the source of indefinitely sustained and
uniform flow of wood and other benefits.
 The difficulty of attaining this goal is greater the longer the production cycle of the benefit or the age of stand on which it is
dependent.
 Sustained yield is most difficult to achieve with timber and other benefits available only from stands that have ages measured
in decades or centuries.
 The fundamental principle of sustained yield is simple.
 Each annual age class, from that of year one to that of rotation age, which is being harvested and replaced this year, must be
equally represented in whatever forest unit is the source of sustained yield.
 It is very important to recognize that foresters almost always manage forests that have mal-distribution of age classes.
 This mean that goal of sustain yield is approached but not achieved.
 It is however important to note that rigid adherence to annual sustained yield would force timber on to the market when
demand was low and withhold it when demand was high.
 However, sustained yield for timber has been prescribed in forest management through the following three methods.
1. Area method of yield regulation:
2. Volume method of yield regulation
3. Combination of both:
1. Area method of yield regulation:
 This consists basically of dividing the total forest area in to as many equally productive units as there are years in the planed
rotation and harvesting one unit each year.
 This is very suitable if only clear-felling or simple coppice systems are being applied because it may not be suitable for other
silvicultural systems for uneven-aged management.
2. Volume method of yield regulation:
 In this method the basic procedure is to determine the allowable annual or periodic felling in terms of volume of wood with
dew regard for the rate of growth, current and potential, and for the volume of growing stock, existing and desired.
 The volume method of yield regulation is really a sophisticated and indirect way of applying the area method.
 In fact, if often depends of regulating diameter distribution and it might better be called as diameter limit cut method of yield
regulation. This is suitable for ideal selection system.

3. Combination of both:
 A combination of both area method and volume method of yield regulation may sometimes be applied as in case of periodic
selection system.
 The above methods of forest regulation are simple in principle but difficult to apply, even if the owner’s policy is to have
sustained yield
 The area method of regulating yield remains the most dependable technique of developing and guiding sustained yield.
Optimum Use of Capital and Growing stock:
 It takes so long for trees to grow that silviculture, especially that for timber production, is powerfully affected by policies about
long term investment of capital
 These are following two quite different kinds of capital investments are made and it is important to analyze them separately.

1. Treatment of monetary investments
2. Investments in growing stock
1. Treatment of monetary investments:
 The more obvious of two kinds of investments is the money actually invested out of pocket in the cost of growing trees and
holding the land beneath them
 A common way of analyzing these kinds of investments is by using compound interest calculations to compare the present
net worth of different course of action
 One of the most important uses of this particular analytical technique is the financial comparison of different systems of
silvicultural treatments.
 Comparison of present net worth help with choices of regeneration techniques, rotation length, thinning programs, logging
methods and many other decisions made in formulating a silvicultural system.
 Operational cost is also an important consideration. So, the systems in which cost of felling, logging, and extraction is less
should be selected to reduce the operational cost or the investment in various operations. Hence, the concentrated systems are
advantageous than diffused systems.
2. Investments in growing stocks:
 The second kind of capital investment in timber management silviculture is the value tied up in merchantable trees that are
standing and growing
 This investment is in income postponed rather than in money actually invested, unless one has recently purchased the trees of
the growing stock
 A good growing stock has a high stumpage value and the money that could be realized from its liquidation represents a
substantial investment
 It is desirable to manipulate the growing stock so that its increase in value represents an acceptable rate of compound interest
return on its own value.
 The assessment of this situation is called financial maturity analysis.
Concentration and Efficient Use of Operations:
 It is important to arrange stands so that costs, per unit of volume harvested will be kept at the lowest level consistent with
other objective
 Transportation is the component of logging costs most affected by the arrangements of stands
 In considering the relationship between silviculture and logging cost, it is crucial to distinguish between area related
transportation costs and those by handling and processing, which are most strongly affected by tree size.
 Concentration of work reduces cost of felling, logging, and extraction operations.
 From this point of view, systems based on concentrated felling and regeneration, offer a great advantage over selection
system which results in diffusion of works
 The clear-felling and simple coppice systems are most advantages, as the regeneration period is the shortest.
 The longer the regeneration period and greater the number of secondary felling, the lesser will be the advantage.
 The concentration of felling and regeneration also makes the supervisions of work easy.
Resolution of conflicting objectives:
 It should be apparent that there is no inherent harmony among the various major objectives sought in managing forests.
 Such harmony can be created only by weighing the various objectives and above said consideration individually and
formulating a silvicultural system that represent analytical compromises within forest management plans created by the same
kinds of procedures
 The disharmony that has been deliberately painted is most evident if one considers all forestry in general.

 Fortunately these conflicting objectives need be resolved only for particular forest or stands.
 Analysis of each situation will usually reveal a few ruling considerations.
 The necessity of giving first attention to these considerations will simplify and govern the solution.
 Sometimes one is faced with two or more problems, each of which is separately soluble but which can be neatly combined in
to a single solution
 The process starts with a consideration of the goals of the forest owners.
 Each of the remaining objectives must receive some attention
 The analytical process generally works downward from the forest to the stand, but not without formation of some preliminary
idea of the range of treatments and results that is silviculturally feasible.
 Foresters are more able to formulate and prescribe silvicultural treatments than such lay people such as legislators,
corporation directors, accountants, or users of forests.
 However, when these other kinds of people represent the ownership of the forest public or private, it is they who determine
the objectives of management and policies of use of the forest.
 The foresters should advise and tell what the potentialities are, but they should then be content to execute the policies.

Advance silvilculture iof

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Advance silvilculture iof