Gmelina

PRODUCTION TECHNOLOGY OF GMELINA

Gmelina arborea is a multipurpose tree belonging to the family Lamiaceae. It is naturally found in both dry and moist deciduous forests and has a great potential for establishing as large scale plantations in the tropics. It is indigenous to India and also found naturally distributed in Pakistan, Bangladesh, Myanmar and parts of Sri Lanka, Thailand, Laos, Cambodia, Vietnam, China, and Yunnan. The species occurs naturally in latitudes ranging from 5 to 30° N and longitudes 70 to 110° E with an altitudinal range of 50 to 1300 m. In India, it has a wide distribution occurring in several States such as Uttar Pradesh, Punjab, West Bengal, Assam, Andhra Pradesh, Odisha, Tamil Nadu, Kerala, Karnataka, Maharashtra, Gujarat and Madhya Pradesh. 

Gmelina is a moderate to large deciduous tree with a straight trunk bearing numerous branches. The species usually attains a maximum height of 20 m with a clear bole at 6-9 m, circumference of 70-85 cm and a GBH of about 1.5 to 2 m. It is a preferred species by farmers, forest departments, ayurvedic industries and other stakeholders due to the versatile utility, rapid growth and high economic returns. It is grown extensively in north eastern India and certain parts of South India.

MAJOR USES

Gmelina wood is used for particle board, matches, packing cases, general carpentry and joinery, furniture components and other household fixtures. It is also used for pulpwood production due to a high kraft pulp yield and low chlorine requirement. Gmelina is an ideal species for carving musical instruments and boat decking. The round timbers are used for posts, house timbers and poles while rotary cut veneers are utilized for plywood. The leaves and fruits are used as fodder. Root is an important ingredient of “Dasamula”, an Ayurvedic medicinal preparation. It promotes digestion and improves memory. Roots are useful for curing fever, heart diseases, nervous disorder, dyspepsia, hemorrhoids, piles and burning sensation. The root decoctions are used in folk remedies to cure abdominal tumors. Bark extract is used for controlling fever and dyspepsia.

CULTIVATION PRACTICES

Gmelina is grown in a variety of soil types, climatic conditions and cultivation regimes in different parts of the country. A general description of soil, climatic and other factors suitable for Gmelina cultivation is given below:

Soil : Gmelina grows well in moist, fertile and well-drained soils. It prefers fairly moist, calcareous soils and alluvial soils with pH ranging from 6.5 to 7.5. It shows poor growth and form in dry sandy soil, shallow or hard pan soil, acidic and waterlogged soils. Similarly, it cannot grow in heavy clay soils. The soil depth and drainage are crucial factors responsible for growth and development of the species.

Climate : It grows at an elevation of 0-1200 m MSL and comes up very well in humid climate with an optimum temperature ranging from 20-30°C. The annual rainfall requirement is 750-2500 mm. It grows very well in the high sunshine with low shade areas.

Seed propagation : Select good mother trees in the bulb garden or seed farm and collect the seeds. The bulb tree blooms in February and the pods are ready for harvest in April-June. The fleshy part of the pods should be removed and dried in the shade. Generally, 2500 seeds per kg will be available. The seeds should be sown immediately in the raised seed beds. After six months the germination capacity of the stored seeds will start to decline. Seeds begin to germinate within 15 days of sowing and last for 35-40 days. The germination capacity of seeds is on average 75 to 85 percent. Well germinated 30 day old plants should be mixed with red soil, sand and FYM in the ratio of 2: 1: 1 and filled in polythene bags and planted. Plants planted in polythene bags should be hardened in the shade for 7-10 days to adapted outdoor conditions. By selecting the best mother tree and harvesting them, new plants can be grown using the stems that grow from the base of the tree. Base of the elongated stem about 15-20 cm is soaked in IBA root stimulant solution at the rate of 20 mg per liter of water. Seedlings produced in this manner are found with uniform growth.

Clonal Propagation : Clonal propagation facilitates both production of planting material throughout the year and also increasing plantation productivity through multiplication of high-yielding clones. The best method of vegetative propagation in Gmelina is rooting of coppice shoot cuttings. Coppice shoot production is induced by felling the selected trees at a around 30 cm from ground level. Juvenile coppice shoots emerge 20-30 days after felling and 60 days old shoots with 15–20 cm length and 1.0–1.5 cm diameter are used for rooting. Cuttings are prepared by excising the leaves and treating with 1% aqueous Bavistin (2-methoxycarbamoyl benzimidazole) for 3 min. The top end of the cutting is sealed with paraffin wax to avoid moisture loss and bottom end treated with 2000 ppm of IBA. The cuttings are planted in 40 cc root trainers containing vermiculite as rooting substrate and placed inside a poly tunnel (size :70 × 90 × 60, relative humidity: 80–90% and temperature: 30± 2 °C) under intermittent misting. The poly tunnels were placed in a 70% shade house. New sprouts emerge from the coppice cuttings within a week and rooting occurs 30 days after planting. Rooted cuttings are transplanted into polythene bags containing red soil, sand, farmyard manure (2:1:1) and hardened in a shade house for 30 days before exposing to full sunlight. The clonal plants are ready for field planting 60 days after shifting to open sunlight.

Clonal propagation through mini cuttings: Mini hedges of Gmelina are established with rooted cuttings by planting them at a spacing of 30 × 30 cm in the mother bed chamber in a poly house. The top of hedges are pruned to promote axiliary shoot production. Generally cuttings with 3 – 6 axiliary shoots are used for the production of planting material.

Land Preparation : Plough the field 2 to 4 times at a depth of 50-60 cm with tractor drawn disc plough or victory plough in order to make the soil into a fine tilth.

Planting : The seedlings/cuttings should be planted in a pit with dimensions holding 45x45x45 cm with a basal application of 5 kg of FYM and 70 g of NPK complex fertilizer plus 10 g of Borax. About 120 days old seedlings/clones can be used for planting. The seedlings are planted with the spacing of 3x3 to 5x5 m. The bund planting of Gmelina about 2 m intervals is being maintained between the trees.

Agro Forestry System : Growing of G. arborea in agroforestry model is commercially practiced in several parts of India. Some of the popular agroforestry models practiced in the State of Tamil Nadu are:

Gmelina + Groundnut

Gmelina + Water melon

Gmelina + Pulses

Gmelina + Maize

Gmelina + Banana

Gmelina + Moring

Gmelina + Chilly

Gmelina + Onion

Multi-tier cropping system also has been followed in Pudukkottai district of Tamil Nadu involving Coconut + Gmelina + Banana + Pepper (Pepper trained on the Gmelina trees). 

Table 1:  Combinations of agri, horti and pasture crops grown with Gmelina under different agroforestry system in Tamil Nadu.

Sl. No

Cropping System

Spacing (m)

Agricultural Crop

1.

Agri Silviculture

4 x 4

Sugar cane, Maize, Groundnut

2.

Horti Silviculture

4 x 4,10 x 10

Oil palm, Coconut

3.

Multi-tier

2 x 2, 5 x 5, 10 x 10

Banana, Coconut, Pepper

4.

Silvi pasture

4 x 4

Cumbu, Napier

Irrigation : Gmelina is a fast growing tree species that requires regular irrigation for better growth and development. Irrigation is to be done at weekly interval. Irrigating Gmelina plantation through drip irrigation system will reduce water requirement and also control growth of weeds.

Weeding : Gmelina is a light demanding species and its growth and development is reduced sharply under poor light conditions. Intensive weeding is hence very essential; weeding should be done three times in the first year, two times in the second year and once a year since third year since planting.

Pruning : Pruning is an important practice in the cultivation of G. arborea in farmland. Pruning decides the growth, clear bole and intercropping ability. Removal of side branches, dead and insect affected shoots should be done in every six months. Regular removal of epicormic shoots is mandatory for better growth and development. Always pruning ratio is to be maintained in 1: 3.

Thinning : It is an important practice to enhance the production of sawn logs. In case of closely planted plantations, the first thinning of alternate rows is to be done at the age of 3-5 years after planting and the thinned woods are used for pulp production. Second thinning should be done at the age of 8-9 years after planting to avoid competition between the trees and to maximize the growth. Thinned wood are used for making plywood and softwood timber products.

Harvest : The circumference of the bulbous tree is about 40 to 50 cm when harvested in 5 to 6 years after planting. The yield is 30 to 40 tons per acre. This will bring in two to three lakhs of income. When the tree is harvested for more than nine years, the circumference of the tree is 90-120 cm. Up to 15-25 meters in height. It is used to make furniture, beds and tables as the perimeter of the tree is large. When the bulb tree is harvested in 8-10 years a tree can weigh up to 500-800 kg. 9-10 lakh per acre and is used in making plywood and softwood timber products.

GMELINA CULTIVATION BUDGET (per acre)

Year

Total No. of Trees

No. of Trees for Harvest

Tree Weight (kg)

Total Weight (Tonnes) 

Rate (Rs.)

Total Income (Rs.)

4th 

650

325

100

32.5

4,000

1,30,000

6th

325

162

300

48.6

7,000

3,40,200

9th

200

163

600

98

10,000

9,80,000

Yearly Income via Intercropping

25,000

1,25,000

Total

15,75,200

Note: The above cost may vary depending on the land type, climate, variety, cultivation practices, pest and disease management, and the market situations.

Sl.No

Expenses

Year

Total amount (Rs.)

1

2

3

4

5

6

7

8

9

1

Land Preparation

10 labours

3500

-

-

-

-

-

-

-

-

3500

2

Ploughing

1 acre

1500

-

-

-

-

-

-

-

-

1500

3

Excavation(digging pits)

650 pits

5000

-

-

-

-

-

-

-

-

5000

4

Farm Yard Manure

2 ton

3000

3000

-

-

-

-

-

-

-

6000

5

Manure and fertilizing

NPK mixture

5000

5000

5000

5000

5000

-

-

-

-

25,000

6

Plant Protection

-

7000

7000

7000

7000

5000

-

-

-

-

33,000

7

Seedlings

Rs. 10/ seedling

6500

-

-

-

-

-

-

-

-

6500

8

Planting

Rs. 5/ Plant

3250

-

-

-

-

-

-

-

-

3250

9

weeding

-

4000

4000

4000

2000

2000

-

-

-

-

16,000

10

Secondary land preparation

-

5000

5000

5000

3000

3000

-

-

-

-

21,000

11

Irrigation

-

5000

5000

5000

5000

5000

-

-

-

-

25,000

12

Pruning

-

4000

4000

5000

-

-

-

-

-

-

13,000

13

Inter cropping

-

10,000

10,000

10,000

10,000

10,000

-

-

-

-

70,000

14

Inter crop harvest

-

2500

2500

2500

2500

2500

-

-

-

-

12,500

Harvest

-

-

-

-

50,000

-

75,000

-

-

3,00,000

4,25,000

Total Expenditure

6,46,250