An increasingly industrialized global economy, rapid population growth, land degradation, land use pattern and role of various human activities have led to dramatically increased the pressure on the natural resources such as the available land for sustaining the livelihoods, and with over exploitation and extraction of the natural resources the ecosystems are becoming unsustainable and fragile since last century. The forest and tree cover of India is 78.92 million ha, accounting for 24.01 per cent of the geographical area. But due to biotic disturbances such as over-grazing, deforestation, shifting cultivation and etc. also effect on regeneration of tree species inside and out side of the forest area.

1. Course no. FOR 501
Course Title : SILVICULTURE
Assignment Topic: Natural regeneration of few species
Submitted to Submitted by
Dr. M. B. Tandel Vikas kumar
(Assistant professor) M.Sc. (FORESTRY)
Aspee college of horticulture & Forestry Aspee college of horticulture And forestry,
Navsari, Gujarat Navsari, Navsari
Email ID: vkskumar49@gmail.com
Contact No.: 9995093698

2. Regeneration-
The Renewal of forest crop by natural or artificial means .
NATURAL REGENERATION-
Regeneration through self sown seed or by coppice or
root suckers .
Sources- 1. From seed- seedling crop-high forest .
2. From vegetative parts -coppice crop-
low forest / coppice forest .

3. Natural regeneration from seed :
It depends upon-
1. Seed production-
2. Seed dispersal-
3. Germination-
4. Establishment-

4. 1.Seed production:
1. Species - moderate or good seed year .
2. Age of trees – middle aged trees .
3. Size of the crown- middle-aged mature trees
with well developed crown .
4. Climatic factors – warmer climate favours .
5. Other locality factors – like insects attack
and girdling , fire injury .

5. Tab:1 below table shows the interval between moderate
and good seed yeas of important Indian species :
Species Moderate seed yr Good seed yr
1. Abies pindrew
2. Cedrus deodara
3. Picea smithiana
4. Pinus
roxburghii
5. Shorea robusta
6. Terminalia
tomentosa
7. Dalbergia sissoo
6
3
3
3
2
2
2
10-11
4-5
5-6
4-5
3-4
3-4
2-3

6. 2. SEED DISPERSAL :
 WIND- All coniferous species , Acacia catechu, Acer,
Adina ,Bombax, Betula, Casuarina, Chloroxylon, Dalbergia,
most of the Dipterocarpus Holoptelia, Populus, Pterocarpus
marsupium, Rhododendron, salix, Terminalia.
 WATER- most swampy and mangrove species ,teak
Trewia, Dalbergia etc.
 GRAVITY- oak, Chestnut , walnut , Aesulus etc.
 BIRDS- Diospyros Mulberry, Prunus, Trema,
Pyros melanoxylon.
 ANIMALS- Anthocephalus, Zizyphus, Prosopis juliflora,
Acacia arabica.

7. 3. SEED GERMINATION :
INTRNAL FACTORS-
a. Permeability to water-
b. Permeability to oxygen –
c. Embryo development- fully developed at the time of
seed fall also may remain dormant .
d. After ripening- chemically not developed seed
undergo the process of after ripening .
e. Seed viability- potential capacity of seed to
germinate .

8. f. Seed size-
g. Germinative capacity and Germinative energy-
Germinative capacity- the percentage ,by number ,of seed
in a given sample that actually germinate , irrespective of
time.
Germinative energy- the percentage ,by number ,of seed in
a given sample that have germinated up to the time when the
rates of germination reaches (i.e. number of seed germinating
per day) reaches it’s peak.
h. Plant percent- percentage of the number of seeds in a
sample that develop into seedling at the first growing season.

9. 2.EXTERNAL FACTORS-
Moisture- activates the dormant embryo by softening
the seed coat
a) Oxygen-
a) Temperature- higher the temperature greater the
germination.
b) Light and heat- most species are indifferent to light
condition for their germination.
c) Seed bed- light burning or shrub cutting

10.  Seed year-
• a year in which a given species bear seed
abundantly.
• designate as good, moderately good, poor or very
poor .
Seedling year-
• a year in which a given species produces
abundant first year seedling .
• designate as good, poor, or very poor.
•A good seed year is not necessarily a good
seedling year .

11. 4. Seedling establishment :
 Development of young regeneration,
natural or artificial, is considered safe
from normal adverse influences .
 longer needs a special protection or
tending operation ( other than cleaning,
thinning and pruning ) .

12. Factors affect establishment of seedlings are :
1. Development of roots- fast root growth seedling
less mortality.
2. Light condition –as young regeneration grow in
age , require more light.
3. Soil condition - soil should have adequate
moisture , nutrients and proper soil aeration.
4. Competition- for light, soil nutrients soil
moisture, growing space.

13. 5. Crop composition- mixed crops are more favorable for
establishment of natural regeneration.
6. Biotic factors- like grazing, burning, lopping & others
forms of human interference like removal of timber etc.
7. Other factors-
 Drip- by exposing roots of tiny seedlings.
e.g. Sal ,Teak.
 Temperature- very high and very low temperature kill the
seedlings.
 Precipitation- drought , rainfall distribution leads to
mortality of seedlings.

14. In short, Development of a forest from seed under
natural condition is depends on :
1.Adequate and well distributed seed supply.
2.Favourable condition for the
-germination of seeds.
-development and establishment of seedling.
3. Favourable condition of undergrowth , ground cover
and overhead canopies so that seedling receive not
only adequate light also free from root competition.
4. Protection against all kinds of injuries.
5. Tending.
6.Control over mixture.

15. Following operation were carried out to
obtaining natural regeneration :
1. Disposal of lot of felling refuse & creation of
clean ground by cutting and burnt down.
2. Sowing or planting.
3. Strip form of regeneration.
4. Weeding & cleaning and at pole stage has to be
thinned.

16. Sources for obtaining seeds or seedlings
in natural regeneration of clear-felled
areas :
1. From the adjacent standing mature forest .
2. Seed already lying dormant in the clear-felled
areas .
3. Ripe seed on the mature trees before they were
clear-felled .
4. Advanced growth already present in the clear-
felled area .
5. Coppice crops .

17. Fig. Clear-felling system.

18. Natural regeneration under clear
strip system :
 Progressive strip system –
Progresses successively in one direction
( usually against the prevailing direction of
the wind ) across the regeneration area .
 Alternate strip system –
Clear-felled strips alternate with unfelled
strips of similar width though they may
narrower or wider also .

19. fig. Shelter wood
system

20. Regeneration felling :
 Seeding fellings –
canopy is opened to provide enough light for the
seedlings to come up and ensure their survival in
the initial stage.
 Secondary fellings –
mother trees are removed in a series of fellings.
 Final fellings –
only when ensuring regeneration has established
itself.

21. Following operation were carried out to obtaining
natural regeneration :
1. Seed supply – distribution of middle age trees, aspects,
presence of advance growth.
2. Light requirement & canopy manipulation –
Size of regeneration, system followed and areas.
Methods to reduce undergrowth density are- regular
cutting back, controlled burning, uprooting, use of
weedicides.
3. Soil condition – Compact, undecomposed organic
matter, excess or shortage of moisture are not
favourble.
4. Burning – beneficial effect on natural regeneration and
soil condition mostly in Sal, Chir, Teak.
5. Slash disposal – treatment or handling of slash for
reducing hazards from fire, insects, fungi and providing
the seeds with access to the soil.
6. Tending operation and protection against damage by
animal.

22. Following operation were carried out to assist
in establishment of natural regeneration :
 Removal of trees of and above the exploitable
diameter .
 Thinnings in tress below the exploitable diameter
.
 Cultural operations .

23. Natural regeneration from vegetative
parts :
 Coppice – plants cut from near ground level, produce a
flush of fresh seeds .
 Root sucker – root of a plant partially or wholly cut to
produce shoot .
 Cutting – part of stem, root or branch is planted in soil .
 Layering – roots developed on a girdled portion of a
branch .
 Grafting – cut part is grafted to another
 Budding – bud is grafted to bark of another plant.

24. Natural regeneration by coppice
:
 Seedling coppice – coppice shoots from the
base of seedlings which have been cut back .
 Stool coppice – coppice shoots growing from a
stool or a living stump .

25. Factors affect natural
regeneration by coppice :
 Coppicing power .
 Age .
 Season of coppicing .

 Height of stump .
 Rotation, silvicultural system .

26. Cedrus deodara
Common name: Deodar, Himalayan Cedar
Family: Coniferae

27. Development & ripening of cone :
 No growth in young cones untill the following spring, by the end of June
or during July they become full sized, and are pale yellowish green.
 They turn chocolate-brown in colour during august, & ripen from the end
of September to middle or end of November.
 Time occupied from first appearance of female cone to the ripening of cone
is about 12½ to 13½ months.
 The ripe cones are erect, brown, ovoid or ellipsoidal 3-4.5 inches long by 2 –
3.5 inches in diameter.
 Cones break up on the tree itself
 Scales & winged seeds fall on the ground and only the persistent axis
remaining on the tree.
 Cones are collected off the trees immediately before they open in early
September to early October.
They are placed in sun for a week & break up.

28. Natural Regeneration:
 Seed years: Every third year is a good seed year with
abundant cone bearing trees.
 Seed dispersed in Oct-Nov remains on the ground
throughout the winter, under the snow and germinates in the
spring during Mar-Apr
 Germination takes earlier in the warmer than the cooler
aspects.

29. Teak :
 The factors affecting natural regeneration
of teak are discussed under the following
heads :
 seed
 light
 frost
 soil
 weeds.

30. Seed (Teak) :
 Teak usually seeds abundantly .
 Shedding of the beginning of dry season is beneficial, as it gets
weathered by alternating dry and wet season in the
premonsoon period .
 The hard seed coat beneath the spongy layer of seed protects
it from premature germination during the premonsoon rains .
 Seed requires some warmth and light for germination , and in
cool shady places, the seeds may lie dormant for years .
 Sowing seed in shaded and exposed plots resulted in 1 and 17
percent germination respectively .
 When light was admitted to the shaded plot after two years, the
dormant seeds got germinated .

31. Light (Teak) :
 The establishment of teak seedling also
depends largely on light .
 In moist localities the seedlings may need light
from the beginning, but in dry and hot localities,
a sudden influx of light may kill the seedlings .
 In the peninsular tracts, light shade of
Dendrocalamus strictus is helpful for
regeneration (Kharche,1974) .

32. Frost (Teak) :
 Seedling shoots are killed by frost, but the
root stock may given rise to stronger
shoots each year, until it is able to rise
above the lever of frost .

33. Soil (Teak) :
 Soils having adequate porosity and humus are
particularly suitable for regeneration of teak .
 In case of dry type of teak forests, limitation of
soil moisture has a telling effect on the survival
of seedlings, Mulching with a layer of grass and
leaves with a little soil in such areas keeps the
ground clean of weeds for the whole year And
help to secure the regeneration .
 In case of moist type of soils, if the ground
cover is dense and adequate, natural
regeneration occurs only in patches .

34. Fire (Teak) :
 This burning is usually followed by a good crop
of young teak and other species. The young
crop is weeded usually three times during the
first rainy season and subsequently until it is
established .
 In the dry type of teak forests the seasonal fires
are harmful and may kill the seedlings .
 Light burning is however, considered
beneficial.

35. Weeds (Teak) :
 Weed growth and ground vegetation are the obstacles to the
establishment of natural regeneration .
 weeds like Lantana definitely discourage teak regeneration .
 Little regeneration survives under vigorous bamboo stands,
however light canopy of bamboo is helpful in the dry and semi-
moist type of forests .
 Effect of weeds is seen through dense shade, annual fires in
the area and desiccation of seedlings .
 On the whole, it is seen that the regeneration is inadequate,
unreliable and deficient in the natural forests and has to be
supplemented with artificial regenerations .

36.  Germination starts in the rainy season and continues for some
time .
 Seed may lie dormant for 1-2 years .
 For germination sufficient moisture and high temperature is
essential (Ghosh, 1977) .
 The growth of the seedling depends upon the soil type, weed
competition, intensity of shade and availability of moisture .
 The growth is better in porous soil than on clayey and stiff soils.
 The effect of moisture is evident on the alluvium favourably
situated to receive annual floods where the dense natural
regeneration will come up .
 However, after the receding of water, the drought brings about
heavy mortality, Natural regeneration therefore remains a
unsolved problem .
Acacia nilotica :

37. Albizia lebbeck :
 In spite of the large quantities of the seed produced almost
annually, the natural regeneration is decidedly scanty and
sporadic .
 Various reasons are attributed for the failure of the regeneration
viz. the fallen and uncovered seed is badly attacked by insects
quickly after rains .
 Browsing and grazing by deer and cattle also causes mortality.
 The ideal conditions for natural reproduction appear to be
loose, fairly moist soil; freedom from weeds, light shade
preferably from the side in the beginning and absence of shade
once the seedlings have established themselves .

38. Terminalia arjuna :
 Dense natural regeneration is often found in
forests where the seed has accumulated
alongside stream banks, germination
commences after the seeds are fairly soaked by
pre-monsoon showers .
 The seed does not germinate readily, if
exposed to the sun .
 Though heavy shade is injurious, side shade is
advantageous (Kadambi,1954) .
 Natural seedling in the forest, may die-back for
6-7 years, developed .

39. Vateria indica :
 Plentiful natural regeneration is obtained in the
neighborhood of seed-bearers as the heavy
seed falls close to the tree .
 The seedling withstand a considerable amount
of shade , but are sensitive to drought, frost and
fire .
 Top canopy shade and lateral growing space
help the progress of natural seedling .
 Retention of 70-100 trees in the top canopy per
ha for shade .

40. Pinus roxburghii:
 The chir pine sheds its seed from April to July .
 The seed does not remain dormant and may begin to germinate
within ten days of falling, provided sufficient rain-fall preceeds .
 The seed germinates under shade of pine forests, however,
under conditions of insufficient light, the resulting seedling
rapidly die-off(Troup,1921) .
Factor affecting natural regeneration are viz :
 Nature of seed bearers
 Light
 Drought
 Topography and soil
 Soil covering and undergrowth
 Fire
 Grazing and grass-cutting etc.

41. Eucalyptus tereticornis :
 The main impediments to natural regeneration
in Karnataka are regarded to be : destruction of
seed by ants, young seedling smothered by
leaf-litter, weeds and grass .
 Eucalyptus leaves are toxic and contain
germination inhibitors, the seed germinating on
the leaf litter fail to reach the soil .
 For establishment of natural regeneration
favorable conditions like good soil moisture,
absence of noxious weeds, worked up soil and
closure to grazing are all required .

42. Dalbergia latifolia :
1. Root suckers: A long tap root is developed in the early
stages of growth. The roots are dimorphous. The root, which
becomes subsequently thickened, has other main roots;
smaller nutrition roots and fibrous rootlets devoid of buds .
 The entire root system spreads both downwards as well as
sidewards into the soil cover .
 Numerous root suckers are formed which lead to the
multiplication of the species. Root suckers are best developed
in moist conditions .
2. By seeds: Seeds fall onto the forest floor during the pre-
monsoon period and germination occurs under favourable
conditions .
 Mortality in such a situation may be due to the extreme dry
conditions; grazing; browsing; trampling by cattle; or poor
drainage etc .