SILVICULTURE OF SAL

1. SILVICULTURE OF SAL
PRESENTED BY:

2. GENERAL DESCRIPTION
• Sal is one of the main commercial timbers of India and
economically most important species of north India.
• It accounts for about 14% of the total forest area in India.
• S. robusta occurs in both deciduous dry and moist
forests and in evergreen moist forest.
• In wetter areas, sal is evergreen; in drier areas, it is
dry deciduous .

3. TAXONOMIC RANK
• Kingdom: Plantae
• Phylum: Magnoliophyta
• Class: Magnoliopsida
• Subclass: Dilleniidae
• Order: Theales
• Family: Dipterocarpaceae
• Genus: Shorea
• Species: S.robusta
• Scientific name: Shorea robusta

4. MORPHOLOGY &GROWTH
CHARACTERISTICS
• Growth Form: A large gregarious tree, seldom quite
leafless with shining foliage. It is usually 45-50m tall;
trunk to 5m dbh (diameter at breast height) in fertile
areas.
• However, most trees would normally attain a height of 18-
32 m, with a dbh of 1.5-2m.
• Crown: Crown is conical or elongated in youth, later
rounded with strong branching system.
• Trunk: Bole is clean and straight. bark of saplings is
greyish brown, smooth, with few longitudinal cracks.
• Older trees bark is dark brown, 1-2cm thick rough with
deep longitudinal furrows.

5. Contd..
• Foliage: Mature leaves are coriaceous, obvate-oblong
(10-25 cm Long10-20cm long by 6-12 cm wide, with 12-
14 pairs of lateral veins.) (broadly oval at the base, with
the apex tapering into a long point)
• New leaves are reddish, later becoming delicate green.
• Flowers: yellowish-white, arranged in large terminal or
axillary racemose panicles.
• Fruit: mature fruit measure about 1.3-1.5 cm long and 1
cm in diameter; it is surrounded by segments of the calyx
enlarged into 5 rather unequal wings about 5-7.5 cm
long.

6. • Sapwood is pale coloured, heartwood is brown, hard
cross- grained, very strong and durable, seasoning slowly.
• Roots: This species has a tendency to develop a long
and deep tap root even at a very young age.

7. NATURAL DISTRIBUTION
• Occupies 2 main regions separated by Gangetic plain.
• Continuous stretch of sal starts with kalesar forest in
ambala( Haryana) on right bank of Yamuna and stretches
eastward, along sub Himalayan region in Assam through
UP, Bihar, Assam, Meghalaya.
• In central region sal occurs in Bihar, WB, Orissa, MP&
CG.

8. LOCALITY FACTORS
• Of the 2 factors of habitat, climate and soil, the former
decides the general distribution of S. robusta; among the
climatic factors, rainfall is by far the most important.
• Temperature: Sal survives up to a maximum temperature of
36°C to 44°C and minimum temperature of 11°C to 17°C and
• Rainfall: needs an average rainfall of 1000 mm to 3500 mm
per annum.
• Soil: Occurs both in hilly regions and grows best on lower
slopes and valleys with deep, moist and fertile soil. Avoids
swampy tracts with poor drainage. Most favorable soil is well
drained moist deep sandy loam with good subsoil
drainage.
• NOTE: Sal is completely absent in Deccan trap( replaced by
teak)

9. PHENOLOGY
• Flowering: appear in late Feb to April
• Fruiting: fruits ripen may to July
• Fruits start falling soon after (regional variation): may to
June-west Bengal, early June- Assam, June- Bihar,
Jharkhand, Uttarakhand, may to July- M.P.
• Fruits weigh : 530-1060 /kg (FRI)
• Avg. seed year expected after every 2 years
• Good seed years every 3-5 years
• Fresh seed – high germinative capacity 80-96%, plant
percent nearly-86%

10. • Seed loses viability rapidly
• Can be stored for nearly 7 days, if packed in lime or saw
dust and kept in shade.
• Seeds do not require any pre-treatment, seeds germinate
soon after falling
• For seed collection ground under healthy, well shaped
and matured trees is cleared and seeds are collected
every morning.

11. SILVICULTURAL CHARACTERISTICS
• LIGHT :Sal is able to persist under moderate shade but it
is a light demander in older stages.
• TEMPERATURE: Young sal plants suffers badly from
frost seedlings and coppice shoots killed by frost, severe
frost can injure crown of poles, killing leading shoots, so it
require protection from frost, however in later stages can
withstand frost.
• MOISTURE: drought sensitive (leads to dying off)
• ROOT-system: long stout taproot ( sal usually does not
produce root suckers)
• COPPICE: Coppices well up to a moderate size. Shoots
produce from side of it near ground level (not from top).

12. Contd..
• SOIL: Well drained moist deep Sandy loam with good
subsoil
• STORMS: due to long taproot system not liable to wind
throw.
• Fire : most fire resistant species compared to other
species, can establish itself in burnt areas where others
cant survive. Despite being burnt back year after year it
recovers slowly.
• However in dry sal regions it can cause hollowness or
unsoundness resulting in loss of quality and quantity of
outturn.(so fire protection necessary)
• In moist sal regions, controlled and regulated burning
useful for inducing and establishing regeneration.

13. DYING BACK OF SAL
• After good seed year, when thousand of seedlings cover
the ground, number of seedlings are greatly reduced by
wholesale dying off and only a proportion may survive.
• Dying back may consist of death of whole stem or only a
portion of stem and growth being carried by new shoots
from axillary buds at different points on stem.
• Recovery takes place only when taproot has developed
sufficiently to withstand adverse influences.
• Dying back is caused due to several factors especially
moisture or water stress , frost action, excessive
competition etc.

14. NATURAL REGENERATION
• NR of sal has regional variations.
• For example: Despite manipulation of various factors NR not
successful in moist and dry deciduous sal forests.
• However in regions of moist peninsular low level and in valley
sal forests of CG,Bihar, Odisha, NR is highly successful.
• Problem not with recruitment but with its establishment.
• Success of NR depends upon:
1) Sufficient seed production: poor seed years are not
uncommon. In fact, in every 6/7th year, poor seed years can
occur
2) Proper & efficient dissemination
3) Good seed germination: Sal seed looses viability rapidly.
Seeds can be stored for 3 or 4 days, may be up to a week
4) Establishment of seedlings in sufficient number : issue of die
back , mass mortality of seedlings under competition and
adverse climatic factors.

15. STEPS FOR SUCCESFUL NR
• Adequate seed supply.
• Combination of good seed year and timely
commencement of monsoon.
• Timely tending operations: dense foliage trees should be
thinned out and light crowned should be retained
• Soil working
• Adequate fencing
• Minimal or controlled grazing
• Burning , before a good seed year.
NR is obtained from tended advance growth.
• Favorable factors: Early and well distributed rains
synchronizing with seed fall and absence of frost.

16. ARTIFICIAL REGENERATION
• Method successful is direct sowing in clear-felled areas
by departmental plantations ,taungya cultivation in
UP,WB, Assam.
• PLANTATION:
• 1.) planting of 22-34 months old basket plants in 60cm3
pits , 3m apart in continuous strips , with 6m apart in
clearfelled or shelterwood areas.
• 2.) Transplants in dona containers more succesful in dry
sal areas with clayey and laterite soil.
• 3.) dona planting done in partly filled trenches with
spacing of 1-1.25 metres.
• 4.) P-Bags containers used in research containers have
given excellent success.

17. ARTIFICIAL REGENERATION
• In clear-felled coupes of sal most successful method of
AR is by direct sowing.
• STEPS:
1. Seeds are sown on cloudy days when the ground is
moist, preferably after rain.
2. Seeds are dibbled with wings sticking up in hoed up
lines 30 cm wide.
3. Prescription is to sow eight lines of Sal alternated by
eight lines of Sal associates.
4. Each Sal line (30 cm wide) consists of 3 rows of seeds,
the rows being 15 cm apart. Seeds are dibbled 8 cm
apart in each row.

18. 5. Sowing of one row is completed first, then followed by
sowing in the second and third rows in that order.
6. The seeds are covered with a light layer of soil, it takes
about a week for germination.
7. Since germination capacity is not uniform over the seed
time which lasts about 3 weeks, this method is adopted to
ensure equal chance of regeneration throughout the area.

19. • In areas where Sal is managed under coppice systems, it
is AR by the method of coppicing.
• METHOD :
• It is managed on a rotation of 15 years. The crop is thus
felled every 15th year, and one or two healthy shoots from
a stool are allowed to grow to pole.
• Regeneration in Sal coppice forests is comparatively
easier and less cost intensive.
• However, if Sal stumps fail to throw up coppice shoots,
Stump planting is also successful ,can also be done to
beat up failed plantation lines.

20. • example: Haldwani division, stumps prepared from
one/two year old irrigated nursery seedlings and planted
in pits 30 cm3 in lines 6m apart and plants spaced 3m
apart in lines (nearly 65% success).

21. OTHER METHODS
• 1.) Stump planting also successful , normally done to beat
up failed plantation lines.
• - stump prepared from one or two year old nursery stock
successful in various plantation divisions.
• - example: Haldwani division, stumps prepared from
one/two year old irrigated nursery seedlings and planted
in pits 30 cm3 in lines 6m apart and plants spaced 3m
apart in lines (nearly 65% success)
• 2.) pre-sprouted stumps of collar diameter 0.6-1.2 cm,
22.5cm roots , placed in p-bags in feb-march , planted in
July- august after 10 months gave nearly 90% survival in
bhabhar- terai regions

22. • Artificial regn. of sal by planting out nursery raised sal
seedlings in (dona, basket or p-bags plants ) or stumps
has not practiced on large scale
• Successful method: raising sal container plants in donas
(made of sal leaves) 6-8cm in diameter and 22-23cm
deep.
• - These are filled with tank silt, earth and cow dung( 2:4:1)
two seeds are sown in each as soon as ripe and
collected, watered and kept in shade till summer.
• -during monsoon, Dona seedlings with 4 leaves and 12-
15 cm inn height are fit for planting out in containers.

23. NURSERY PRACTICE
• The planting stock of sal consists of nursery raised
seedlings.
• Seeds are sown in polythene pots/ hykopots immediately
after collection.
• These are filled with tank silt, earth and cow dung( 2:4:1)
two seeds are sown in each as soon as ripe and
collected, watered and kept in shade till summer.
• The pots are placed preferably on raised beds to facilitate
air pruning and eliminate the phenomenon of root coiling.
• Seedlings established in polypots /hykopots can be
planted during the same monsoon (provided the seedlings
are tall and established), or preferably in the next year.

24. TENDING OPERATIONS
• Intensive tending of young crops in both NR or AR is
important for establishment of seedlings.
• Operations include weeding, hoeing, selective shrub
cutting, fencing, fire-protection etc.
• Sal plantations are seriously affected due to suppression
by weeds and climbers. In areas of taungya plantation
(WB) intensive weeding is done by the villagers.
• Sal plantation requires at least 5 weeding/ cleaning during
the first year, and such weeding/ cleaning should continue
upto 5 years.
• Recommended thinning operations: mechanical (C grade)
thinning in 5th year and silvicultural thinning in 10th, 25th
and 35th year.

25. Contd..
• Sal plantations which are raised with seedlings, suffer
most from moisture stress during the dry season and
biotic damage during initial years.
• For successful establishment of Sal seedlings
• (i) providing fencing to the young plantation for a couple
of years, and
• (ii) making provision of irrigating the Sal blocks in the first
two years during the dry season.

26. PARASITIC PLANTS, WEEDS, INSECTS
& ANIMALS
• Obnoxious weeds such as Mikenia, Eupatorium and
Lantana are serious threats to young seedlings of Sal.
• Sal is also very vulnerable to attack by climbers.
• ANIMALS: Wild animals like elephants, bison, pigs, deer,
monkeys and rats cause damage to Sal crops at various
stages.
• Domestic cattle grazing causes mechanical injury to
young crops and physical deterioration of soil.
• INSECTS: A large number of borers of bark and wood,
defoliators, sap suckers, fruit and seed eaters have been
recorded.

27. • most destructive is Sal heart wood borer,
Hoplocerambyx spinicornis , it attacks dead and dying
trees.
• Sal suffers from heart-rot due to three major fungi,
namely Fomes caryophylli (heart rot), Hymenochaete
rubiginosa (root-rot) and Fomes fastuosus (butt-rot),
which cause serious economic loss.
• Trees between 15 and 35 years are mostly susceptible to
attack by heart-rot fungi.

28. SILVICULTURAL MANAGEMENT
• Worked under variety of silvicultural systems in accordance with local topographical factors.
• Both coppice regeneration and planting of seedlings are used in plantation systems. Young
plants grow quickly, attaining top heights of up to 6 m after 6 years.
• In MP,CG& Bihar: uniform, irregular- shelterwood, selection, clear- felling with natural
regeneration.
• In WB,Assam, UP: 1.) clear felling with artificial regeneration. It is also ideally used for
growing under taungya systems( in WB).
• 2.) simple coppice, coppice with standards: sal requires a lot of light, also it coppices well.
Rotations of 30-40 years are used when coppice regeneration is practiced, and 80-160 years
for high forest regeneration.
•

29. SILVICULTURAL MANAGEMENT
• Worked under variety of silvicultural systems in accordance
with local topographical factors.
• In MP,CG& Bihar: uniform, irregular- shelterwood, selection,
clear- felling with natural regeneration.
• Sal plantations are to be worked on a rotation of 50 years
under the silviculture system of clear felling followed by artificial
regeneration.
• In WB,Assam, UP, Odisha: 1.) clear felling with AR& NR. It is
also ideally used for growing under taungya systems( in WB).
• 2.) simple coppice, coppice with standards: sal requires a lot of
light, also it coppices well. Rotations of 30-40 years are used
when coppice regeneration is practiced, and 80-160 years for
high forest regeneration.

30. COMMERCIAL USES
• Sal wood is very hard , tough and heavy, heartwood is very durable
naturally but sapwood requires treatment before use.
• Timber is difficult to saw and work with due to interlocked fibers.
• Wood is very durable and is used for building bridges, for railway
sleepers. Resistant to attack of white ants it is in great demand for
construction works, mine props, piles, boat building, well
construction; the wood is also used for furniture, tent poles and
pegs, carriages, wheels etc.
• It is good firewood and makes very good charcoal.
• The leaves are made into plates which are in good demand in the
market. The well-known ‘sal butter’ is extracted from the seeds; it is
used as a luminant, a substitute for butter in chocolates, and as
cooking agent.

31. • Sal bark is useful tanning material.
• Sal also yields a vegetable oil on extraction.
• Medicinal uses : The resin is used in the indigenous
system of medicine as an astringent and detergent and is
given in diarrhea and dysentery.
• It is also used as an ingredient of ointments for skin
diseases and in the ear troubles. It is also used in the foot
care cream.
• The fruits of the Sal tree are used in the treatment of
excessive salivation, epilepsy, and chlorosis.
• The powered seeds have insecticides properties. The
powered seeds are even used to treat dental problems. It
cleanses the skin of oily secretion and is used as the
cleanser for washing hair.