CASUARINA : A TREE FOR WASTELAND DEVELOPMENT

Botanical Name : Casuarina equisetifolia

Family : Casuarinaceae

Introduction

Casuarina equisetifolia is the most popular farmforestry tree in the coastal lands of Andhra pradesh, Orissa, Tamilnadu, West Bengal, Maharashtra, Gujarat & Karnataka. Casuarina resembles feathery conifer in general appearance. Almost all of the approximately 35 casuarina species produce top-quality firewood. They are rapid-growing, carefree species for sites and climates as varied as coastal sand dunes, high mountain slopes, the hot humid tropics and semi-arid regions. They tend to be salt tolerant, wind resistant and adaptable to moderately poor soils. Although they are not legumes, they do have the ability to form root nodules and fix atmospheric nitrogen. Casuarina equisetifolia can attain heights of 50 m with diameter of around 1 metre. However, it is generally only 15 - 25 metres tall.

Origin & Distribution :

The species is indigenous to sandy shores and dunes along the coast of Chittagong (Bangladesh) Tenasserim and in Little Andamans. It is also found in North and North East Australia, some pacific islands, Indonesia, Malaysia, India and Sri Lanka. It has been introduced for firewood, beautification & other purposes to India, Pakistan, East, Central & West Africa, West Indies, Florida and Gulf of Mexico.

Habitat :

It thrives best in close proximity to the sea on loose sand, growing sometimes within a few yards of high-tide level, and even with its roots in the sea. In its natural state it is gregarious, forming pure crops with little or no undergrowth except grass and a few coastal shrubs. It is grown as an ornamental tree on various soils in India but does not thrive on clay, preferring a sandy soil. On badly drained ground subject to inundations, the trees become unhealthy and die off whereas on sandy soils where the water-level sinks top low in the dry season they tend to become stunted and even bush like.

Traits suiting for Wasteland Development:

The important characteristics which makes it a suitable species for wasteland development are as follows:

• Adaptable to wide range of habitats.
• Fast growth.
• Salt tolerant, drought resistant.
• Ability to fix atmospheric nitrogen ( forms root nodules in symbiotic association with the soil Actinomycetes Frankia that fixes atmospheric Nitrogen).
• Ability to reclaim land and stabilise sand dunes. In south India, it is considered the best species for colonising sand dunes. In certain parts it is used to check dunes near farmers fields, fisherman's dwellings, roads, railways and ports.
• Desirable stem, crown and branch characteristics for Shelterbelts and windbreaks and Agroforestry. Planted as shade tree in coffee plantations.

Silvicultural Characteristics:

Climate:

Casuarina is a fast growing, drought hardy, care free species for sites and climates as varied as coastal regions, hot humid tropics and even semi-arid regions. The tree remains unaffected even by cyclones in coastal areas. It can be grown upto an altitude of 1500 metres. It tends to be bushy when the water table is low and dies when the water table rises to the surface level. The species does not coppice and is not frost hardy but can withstand low temperature.

Temperature :

It is mainly planted in areas with tropical & hot subtropical climates with the mean annual temperature being 28⁰ C. It is light demander requiring bright sunshine for best growth and development. The monthly mean maximum temperature in its native area is 15⁰ C - 33⁰ C, but it is adapted to a wide range of temperatures. On the coasts of the Indian Peninsula, where it thrives well, the absolute maximum shade temperature varies from 35.56 to 41.11⁰ C and the absolute minimum ranging from 7.22 to 17.22⁰ C.

Rainfall :

In its natural habitat, annual rainfall varies from 700 to 2,500 mm, often with a dry season of 6-8 months. However, it has been planted successfully in areas with annual rainfall as little as 200-300 mm or as much as 5,000 mm.

Altitude :

This is a low land tree that can be planted from sea level upto 1,500 m.

Soil:

The tree thrives best on loose sandy soils, laterite, rich loamy soils & some marshy places in open areas, where pH varies between 4.8 and 8.4. It prefers sandy soil with high water table during the summer. The species can also grow in saline & alkaline soils. Heavy, clayey soils & soils with poor drainage are detrimental to its growth. This may be because of the reason that the activity of nitrogen fixing bacteria in the root nodules is inhibited in such soils. Good plantations can be seen on laterite soils and well drained sandy loams. The tree is able to survive on poor soils because of its capability to trap atmospheric Nitrogen. The soil includes coastal sand, shifting sterile sand, river alluvium, sandy loam with high water table, red loam, red gravelly loam and hard laterite etc. Topography ranges from coastal flats, to very gently undulating terrain.

Nitrogen Fixing Ability:

Casuarina equisetifolia have root nodules containing nitrogen-fixing actinomycetes micro-oganism called Frankia. They are, therefore, not dependent on soil nitrogen for good growth. The species is moderately tolerant to calcareous and slightly saline soils and is a very poor performer on heavy soils such as clays. It can withstand partial water logging for a very short period.

      Artificial Regeneration :

The use of cuttings for propagation are on the increase due to its better performance in terms of faster and better growth as compared to plants raised from seeds. It is easily propagated by rooting of stem cuttings, lateral or side shoots, terminal twigs, heel cuttings or basal sprouts. Suitable cutting material is 2 mm in diameter and 10-15 cm in length and rooting is enhanced through use of the hormones like IBA or IAA.

Air layering on branches 1-2 cm in diameter from middle aged trees yield better results than cuttings from old trees. Vegetative Propagation through air layers cutting, stump cutting and suckers is also being used. Cladodes 5-7 cm in length are found to be an excellent plant material for vegetative propagation. Nowadays, clonally propagated plants are being used extensively by the farmers.

Nursery technique :

Ripe cones are removed from branches of matured trees of 10 to 25 years old & are placed in wooden or metal trays for sun drying. As the viability of seeds is low, fresh seeds from ripe cones just before their dehiscence from 12-18 year old trees are best for sowing. They are collected, dried and stored in earthern jars. Cones are treated with 10% BHC powder or any other insect repellent to keep ants away. Seeds separate from the cones in three days. On an average, 250 cones weigh one Kg and yield 22 gms of seeds per cone. Fresh seeds collected from genetically superior trees are used for raising nursery. Seeds retain their viability for a few months. Though, no seed treatment is necessary, it is advisable to soak the seeds in water for 24 hrs. before sowing. Seeds are sown usually in the month of November in well prepared and manured beds. The nursery beds ( raised ) of 10m X 1m are prepared with light and porous soil mixed with fine manure and ash. The width of the seed bed is kept one metre in order to facilitate hand watering & weeding from both the sides.

A seed rate of 2-3 gm per bed has been observed to produce 400 to 500 seedlings. Usually, sowing is done in the months of November and December. Before sowing, beds must be well watered so that winged seeds stick to moist surface. A thin layer of soil is sprinkled to cover the seeds. Watering with fine rose cane is carried out twice a day for the first 15 days and once a day for next 30 days. Watering is done until the seedlings attain a height of 30-60 cm. It is advisable that brushwood / Paddy straw are slightly spread on the bed to check evaporation and to prevent damage to emerging seedlings while watering. The entire bed is dusted with 10% BHC Powder. The mulch should be thinned gradually as the seedlings appear.

The seedlings may be transplanted after 3-4 weeks in polythene bags or allowed to grow on the seed bed itself. Germination percentage is about 70. Germination is completed in about 10 days and seedlings attain 10-15 cm height in 6 to 8 weeks. At the end of 150 days the seedlings attain a height of 30 to 40 cm and are ready for planting in the field. Inoculation of the seedlings and cuttings with a pure culture of Frankia is recommended when C. equisetifolia is introduced to a new area. This is done by applying a water suspension of the inoculent to the seedlings (or) cuttings.

Site Preparation:

In sandy sites & wastelands very little preparation is done in India. In sandy soils planting is done immediately after pitting. The soil is well pulled & naked seedlings are planted. In hard soil, 30 cm³ pits are made and the soil is allowed to weather for a few weeks until planting time. Pits of 45 cm³ are made for planting container seedlings.

Methods of Planting:

Row Planting: Normally row planting is carried out in coastal areas which reduces the wind velocity to a great extent. About 50 - 100 rows of trees serve as best shelter belt.

Line Planting: Line planting in coastal islands helps in reducing the wind force and stabilising the sand dunes.

Cluster planting: The latest method which is becoming popular with the farmers is cluster planting. In this method 2-3 seedlings are planted at each spot at a wider spacing of 2m/3m. Cluster planting provides more space for agricultural inter cropping than planting singly at closer espacement.

Normally 9 months old seedlings with a height of 30-45 cm with ball of earth are planted out on the onset of monsoon. When casuarina is planted on pure coastal sand, pits of 30 cm³ should be dug. In other areas, pits of 45 cm³ are necessary. The area should first be thoroughly ploughed and cleared of all bushes. In every pit, 5-10 gms. of insecticide should be mixed to prevent white ant attack. About 100 gms. of chemical fertiliser should also be mixed. Weeding cum soil working may be done periodically for better growth. Irrigation during dry months in first two years will help in better growth. Poly bag plants give better survival and growth against naked plants.

Transplanting:

The first transplanting of seedling is carried out after 6-18 months of sowing with the onset of South West monsoon on the west coast and at the time of North-East monsoon on the East coast. During rainy season the seedlings root well even if planted late.

The seedlings of 7-10 cm height are pricked out on the previous evening or early morning in polythene bags, containing earth and manure & placed 7-8 cm apart in beds in the open & watered thrice a day but, care has to be taken to prevent damping off. These are again transplanted in the field when 30-60 cm in height.

Espacement:

As both poles & firewood can be obtained from casuarina and as poles are sold at a much higher value, causarina should be planted at the spacing of 3m x 2m . i.e. 1600 plants / ha to get the maximum number of poles. However, on coastal sands the spacing can be 2m x 2m. The wider spacing will result in getting a greater number of bigger sized poles and so earn more money than the closer spacing of 1m x 1m.

Ploughing is possible when the distance between rows is atleast 3m. However, our recommended spacing is 3m x 1.5 m which will permit inter cropping if farmers desire to go for it.

For government owned plantations the planting density varies from 1600-2500 per hectare at 2.0 x 2.5 m spacing & single seedlings are planted in each pit. In private holding the number has been reported to be 8000-10000/ha at 1x 1.5m.

As both poles and firewood can be obtained from Casuarina and as poles are sold at a much higher value, Casuarina may be planted at the spacing of 3m x 1.5 m accommodating 2222 plants per ha. to get the maximum number of poles.

Inter cropping :

The intercrops like groundnut, cucumber, water-melons in sandy soil, sesamum in red soil and pulses in heavy soil may be taken with Casuarina Plantations. Where irrigation is possible bananas and tapioca can be raised successfully.

Irrigation:

Casuarina responds very well to irrigation. Flow irrigation or irrigation by drip by burying holed earthenware pot by the side of the plant, is very beneficial. Irrigation results in 30-40% increase in yields.

Cleaning:

Being a light demander, cleaning is essential. Overhead shade is avoided. Even the removal or lopping of inferior growth (including individuals of the farmed species, climbers etc.) interfering with light, gives better growth of casuarina.

Weeding & Pruning :

In the first year 3 weedings are necessary. When ploughing is resorted to, weedings from the second year may not be necessary. Pruning of side branches is not necessary. Pruning of branches for intermediate yield is likely to affect the growth of the plant & returns at the time of felling. In India pruning is done in the third year wherever close planting is followed. Branches are pruned close to the main stem to a height of 2-2.5 m.

Ploughing:

Ploughing in between the rows twice a year is absolutely essential. This loosens the soil, allows more water to percolate in the ground and helps growth.

Biofertiliser application & Nitrogen fixation:

Casuarina seedlings are inoculated with Frankia, in the nursery. Frankia is a genus of Actinomycetes that invades root hairs of host plant, develop nodules and fixes atmospheric Nitrogen by virtue of its symbiotic association with casuarina roots. Although not a legume, casuarina has the ability to form root nodules and fix atmospheric Nitrogen. The plant produces both effective & ineffective nodules, the former are pink, cylindrical (or irregularly) lobed and present on roots of all orders; the latter are on few, small, spherical present on roots of secondary and subsequent orders.

Nitrogen fixing property of the plant is useful for the cultivation of the plant in poor soils and also for subsequent species planted in the area.

Uses:

There is a great demand for casuarina poles for scaffolding, centering, roofing etc. Poles are extensively used through out India as props in agricultural crops like banana, tomato, betel vine etc. The wood is used for manufacture of beams, boat building, electric poles, fences, furniture, gates, house posts, piling, rafters, tool handles, wagon wheels and yokes.

It is one of the best firewood's in the world with high calorific value of (4950 kcal/kg) extensively used as a fuel and is used for the manufacture of charcoal. It also burns when green. In fact when the tree is felled, it is converted and marketed in atleast 4 forms: Stumps, thicker branches, finer branches with needles and billets of 1m long. These products meet the various needs of both the rich and the poor. The stumps are exceptionally good for making charcoal.

The wood is suitable for paper pulp and is a promising raw material for the manufacture of paper for writing, printing and wrapping. It can also be used to prepare hard boards and chip boards.

The bark is reddish maroon & blue black in colour and is a tonic and astringent. It is useful in treating diarrhoea and dysentery. Its powder is used for the treatment of acne. A lotion of it is reported to be efficacious as gargle for soar throat, in beri-beri, in coughs, ulcers, constipation and stomach ache. The bark contains catechol type tannins (6-18%). The fresh bark is commonly rubbed on the fishing lines to toughen and preserve the fishing nets.

The needles are made into compost and is used as manure. They are powdered and boiled in oil and applied as a remedy in diseases of the ear. Their extract exhibited anti cancer activity.

Casuarina poles are in great demand for construction of buildings. They are also used for hutments. Firewood of casuarina plantation is greatly sought after. Casuarina plantations can also be used as wind belts and anti-sea-erosion belts along seashore.

Use in Environmental Conservation:

Casuarina forms good shelter belt plantation and also helps in stabilising sand dunes. Extensive shelter belt plantations are raised in coastal areas of West Bengal, Orissa, Andhra Pradesh, Tamilnadu, Kerala and Karnataka.

It protects soil erosion by reducing wind speed. The fine network of sub-surface roots also protects the soil against rain and wind. Because of its capability to fix atmospheric nitrogen, it improves the environmentally degraded soils.

Soil Conservation & Reclamation:

The plant is extensively cultivated in coastal region for soil reclamation and for soil erosion control. By planting this species, numerous stretches of land on the sea coast have been reclaimed, where other species can be subsequently introduced. This is suitable for grassy banks, estuaries, river banks and water ways also. It is grown as evergreen hedges, shelter belts, wind breaks, avenue trees and as sand binder. It is also recommended for Agro and Social Forestry.

NABARD assisted R&D project on Development of Agroforestry Models :

NABARD assisted R&D project on Development of Agroforestry Models for various Agro-ecological Regions was carried out by the Institute of Forest Genetics & Tree Breeding, Coimbatore. The study reveals that there is a possibility of developing different Agroforestry models using Casuarina as a main species. Out of the research findings the following models might be successful for commercial use / replication.

S.No Models Crop Combinations

1 Agri-Silviculture Casuarina + Maize / Fodder Sorghum

Casuarina + Vegetables (Chillies / Tomatoes / Pumpkin / Groundnut)

2 Silvi-Horticulture Casuarina + Mango

Casuarina + Coconut

Casuarina + Banana

Casuarina + Teak + Papaya

Casuarina + Drumstick + Hybrid Tomato

Casuarina + Tamarind + Drumstick

Casuarina + Teak + Eucalyptus + Guava

3 Silvipasture Casuarina + Napier grasses

4 Bund Planting Casuarina as Wind Breaks

5 Block Planting Block planting of Casuarina

6 Line / Boundary Planting Boundary planting in single as well as double rows.

Casuarina + Teak on Boundary

Casuarina + Coconut as line planting

7 Homestead Multi-storeyed Cropping System - Teak / Casuarina / Banana / Vegetables.

Investigations on different models with Casuarina as one of the trial species have shown that Casuarina is one of the most suited spp in Agroforestry.

Pest and Diseases:

In nurseries, seedlings infested by sap sucking aphids, mealy bugs and scale insects become weak and wilt. Defoliation by snout weevils, crickets and grass hoppers is the other type of problem. Termites also take a heavy toll of seedlings and saplings by destroying the root system. Termites are the root destructors reported from young casuarina plantations.

A number of live tree borers are also found causing moderate damage to saplings and trees. The bark feeder Indarbela quadrinotata, I. tetraonis, the root and shoot borer Coelosterna scabrator and Zeuzera coffeae are the common borers attacking the trees.

The larvae of Oryctes rhinocerus is reported to cause destruction in young plantations by damaging roots. Several insects have been reported attacking the tree. The crickets chiefly Brachytrypes achatimus & B.portentosus attack the tree. The mealy bugs such as lcerya aegyptiaca, I. formicarium and Pericerya purchasi and Labioproctus sp also have been recorded attacking the tree. Ants, crabs and grass hoppers are also major pest in the nursery.

For heavier infestations, application of pesticide (preferably systemic insecticides) is likely to be the most effective mangement tool.

Nursery Diseases:

Damping off, Seedling blight, Stem canker and Seedling root rot are the diseases encountered in nurseries. It occurs usually due to water stagnation and poor light penetration. Seedling blight and Stem canker caused by Rhizoctonia solani have been recorded in 2 - 3 months old seedlings. Pink disease caused by Corticium salmonicolor causes severe branch and stem cankers in 2 - 3 year old plants. Root rot caused by Ganoderma lucidum heart rot of standing trees caused by Polyporus glomeratus, Fomes fastuosus and F. senex.

Stem canker and die back can be controlled by removal of affected shoots and application of Bavistin at (0.01%). The stem wilt / bark blister disease caused by Trichosporium vesiculosum is the more serious disease and is favoured by excess water and congestion. It can be prevented by avoiding pruning and lopping of branches and introducing sanitary practices such as trenching.

Cost of Cultivation :

The cost of cultivation will depend upon the extent of the area to be planted. The cost of cultivation for one hectare at an espacement of 3m X 1.5m i.e.. 2222 plants/ha has been worked out at Rs.24,596 / ha which is shown in the Annexure - I. Fencing is not always necessary as the plant is not browsed.

Annexure - I :Cost of Casuarina equisetifolia cultivation in one Hectare

Espacement : 3M x 3M Wage Rate : Rs. 50 / MD

No. of Trees / Ha : 2222 Casualty Replacement: 20%

Survival / Ha : 1778

 

* Intercropping can be taken up in first year depending upon the nature of wastelands and the inputs available.

** Since, income from intercropping is insignificant, the same has not been considered while calculating economics.

Growth and Yield :

At 3m x 1.5 m spacing each ha. will be planted with 2222 seedlings. About 1778 (80%) of them are expected to grow into poles. About 1422 (80% of survival) of good sized poles with a market value of Rs. 50/- (Approx.) each will be obtained after 5-6 years. Additionally about 25 tons of fuel wood at farm gate price of Rs.500/ton will be obtained.

1.Pole 1422 Nos. @ Rs. 50/- each - Rs. 71,100/-

2.Firewood 25 tons @ Rs. 500/ton - Rs. 12,500/-

TOTAL : Rs. 83,600/-

Economics:

The financial analysis with the above parameters of the investment cost and yields, the IRR works out to 41.54 %. A detailed economics has been shown in the Annexure- II.

Annexure - II : Economics of Casuarina equisetifolia in one Hectare

Margin Money, Interest Rates :

NABARD stipulates beneficiaries contribution to the project cost in order to ensure his stake in the involvement. Such margin money varies from 5% to 25% depending upon the type of investment and the class of borrowers.

The rate of interest to the ultimate borrowers will be decided by the financing banks which are subjected to revision by RBI/NABARD from time to time.

Repayment of Loan:

The entire loan amount with interest will be repaid in 5 years from planting. However, as there is no income generation during the first 4 years, the interest will have to be deferred for first 4 years.

Review of Private Plantation Companies & Follow up action by SEBI:

Recently private investments are forthcoming from companies raising plantations with or without involving public equity. As such this is a welcome effort to meet the objectives laid down in National Forest Policy. However, the promises made by such companies are apprehended to be unrealistic. Hence it is essential to look into the claims made by these companies to prevent exploitation of investors as well as to provide adequate safeguards that the investment raised are properly utilised and the confidence of investors in afforestation activities does not get a jolt.

Therefore, Ministry of Environment and Forests constituted an interdepartmental committee to study the growth rate and Economics of private plantation companies and to ascertain the truth behind their claims. On the basis of the detailed analysis of the data collected, technical information available, and observations, the committee made strong recommendations. Based on these SEBI has cautioned the investors through public notice which may be followed.