Silvicultural characteristics of three Terai species of Nepal

Pratikshya Paneru M.Sc.Forestry Roll No.7

Presentation outline

Introduction

Silvicultural characteristics of three Terai species

• Shorea robusta

• Dalbergia sissoo

• Acacia catechu

Conclusion

Introduction

Silviculture is the branch of forestry which deals with the establishment,

development, care and reproduction of stands of timber (Toumey and Korstian).

It is the art and science of cultivating forest crops(Forest Research Institute,

Dehradhun).

For the effective management and fulfilling the objective or goals of forestry,

silviculture is required and it is very much important to understand the silvicultural

characteristics of the tree species.

Nepal has the topographic variation from the 50 meters above the sea level to the

southern border to the highest peak of the world (8,848 meters) to the north.

Introduction cont……

Nepal has tropical climate in the south and temperate and alpine climate in the

north and the forest types vary accordingly.

Nepal has a very diverse flora with 35 forest types, as classified by Stainton

(1972). These forest types are categorized into ten major groups: tropical, sub-

tropical broad-leaved, subtropical conifer, lower temperate broad leaved, lower

temperate mixed broad leaved, upper temperate broad leaved, upper temperate

mixed broad leaved, temperate coniferous, sub-alpine and alpine scrub forests.

Terai region of Nepal is dominated by tropical forest and from the tropical forest

species three tree species Shorea robusta, Dalbergia sissoo, Acacia catechu are

selected to study the silvicultural characteristics.

Shorea robusta

• Local name: Sal

• English name: Sal

• Scientific name: Shorea robusta

• Family: Dipterocarpaceae

• Natural occurance: It is commonly found in Bhabar, Terai and Dunes, tropical and

subtropical zone of Nepal between 50-1500m altitudes (Jackson 1994). Stainton (1972)

distinguishes sal forest of Nepal into two types: 1). Bhabar, Terai and Dun sal forest 2).Hill

sal forest.

Morphological characteristics

• Leaves: Leaves are simple glabrous or shiny, ovate-oblong and

coriaceous. New leaves appear in March-April.

• Flower: Flowers are pale yellow in color; which are in lax, axillary

or terminal panicles. Flowering begins in March -April.

• Bark: .Bark is reddish brown or grey, smooth of longitudinally

fissured.

• Fruit: Fruits are ovoid, with five wings, three longs and two short

and fruiting in May-July.

Silvicultural characteristics of Shorea robusta.Light Light demander

Frost Moderately frost hardy.

Drought Drought sensitive, show frequently dying back phenomenon.

Fire One of the most fire-resistant of tropical region.

Soil It grows well in a well-drained, moist, sandy loam soil.

Coppice It coppices well up to 20-30 cm in diameter.

Graze and Browse Sensitive to grazing and browsing

Tree nature It is deciduous for a short time. A large tree exceptionally reaching a height of 45m, in hills it rarely exceeds 15 m. it is on of the gregarious forest tree species.

Major associates Terminalia tomentosa ,T. belerica , T. chebula , Adina cardifolia ,Anogeissus latifolia, Lagerstroemia parviflora.

Dalbergia sissoo

• Local name: Sissoo

• Scientific name: Dalbergia sissoo

• Family: Leguminosae

It is a medium to large sized nitrogen fixing deciduous tree growing up to 30 m tall

and 80 cm in diameter.

In Nepal it grows up to 1500 m altitude (Jackson 1994). It is a native Terai species

mainly found associated with Acacia catechu.

Morphological characteristics

• Leaves: leaves are alternate and odd pinnately compound (3-5 leaflets each).

Leaflets are broadly oval and leaf shedding in Jan-March.

• Flowers: Flowers are yellowish white flowers are born in bunches (panicles) in

the leaf axis and appear between March -May.

• Fruit: Yellow brown pods that turn dark brown as they ripe in Dec-Jan.

• Seed: Kidney shaped seed. Do not naturally split from the pods which drop off

the tree.

Silvicultural characteristics of Dalbergia sissooTree nature It is a large deciduous tree with clear bole. It is often gregarious on new alluvial lands or

river banks.

Light Strong light demander

Frost Frost hardy

Drought Droughty hardy

Fire Moderately fire resistant

Soil Grows well in alluvial soil but poor growth on saline, heavy clay soil. It does not grow in waterlogged areas.

Coppice It coppices and pollards freely and produces abundant root suckers, especially when the roots have been damaged.

Associates Good association with Acacia catechu on freshly deposited soil.

Graze and browsing

Grazing and browsing sensitive i.e, young are very liable to damage by grazing and browsing animals.

Other Nitrogen fixing, seedlings are sensitive to weed and grass competition.

Acacia Catechu

• Local name : Khair

• Scientific name: Acacia catechu

• Family:Leguminosae

• Natural occurance: In tropical zone,200-1400m(Tisc).It is 8-

15 m tall deciduous tree with light feathery crown and lives

upto 60 years.

• Leaf: Leaves are alternate bi-pinnate. Leaves shedding during

February; new leaves appear during April-May

• Flower: Flowering commences in June and continues till July to

August; flowers are pale yellow in cylindrical spike.

• Fruit: Pods are glabrous, flat and oblong.

• Seed: Seed ripens between November- March.

• Bark :Bark is dark grayish brown; exfoliating in long, narrow stripes.

Morphological characters

Silvicultural characteristics of Acacia catechu

Light It is a strong light demander and does not tolerate any kind of suppression.

Frost Frost hardy

Drought Very drought resistant

Fire Fire resistant

Soil Prefers well-drained coarse, gravelly and alluvial soil

Coppice Coppices well; produces root suckers

Associates It makes good association with Dalbergia sissoo; common associates are Anogeissus

latifolia,Diospyrous melanoxylon, and Lagerstoemea parviflora, Terminalias species.

Tree nature A moderate sized deciduous tree

Root system Develop a strong tap root system; can withstand flooding.

Uses

Timber

Fuelwood

Fodder

Gum and resign: oleo-resign from the sal tree is widely used as incense,and from the khair tree

is used in mastectomies.

Tannin:Cutch from the Khair tree is used for tanning and dyeing pulp and paper .

Sissoo and Khair are nitrogen fixing species and used as agroforestry species. They helps in

soil conservation.

Oil from the sal seeds is used in making soap.

Sal leaves are also used for making temporary plates.

CONCLUSION

all the three species are strong light demander and frost hardy species

Sal is drought sensitive and frequently die back phenomenon is observed

but Sissoo is drought hardy and Khair is very resistant to drought.

These species are moderately fire resistant and all the species coppices

well. So silviculture systems like simple coppice, coppice with standards or

coppice with reserves are also applicable for forest management.

Seedlings of these species are very sensitive to grazing and browsing.

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