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Eucalyptus Plantations in Sri Lanka: Environmental, Social, Economic and Policy Issues - H.M. Bandaratillake

Conservator of Forests, Sri Lanka

ABSTRACT

Eucalyptus are 20% of major reforestation plantings for timber and fuelwood; uses also include wind protection and honey. Advantages include: adaptability to a wide range of altitudes; climates and sites; high growth rate; tolerance of low fertility. Species are classified for use in dry, wet, intermediate zones and in upland locations. Forward annual plans are for 4,000 ha of this, 10-15% will be eucalypt. Main demand is transmission poles, sawn timber and railway sleepers; fuelwood is a secondary product but E. camaldulensis and E. tereticornis are grown on short 7 year rotations for this. Eucalypt (14 yrs.) soil studies noted lower organic matter, N and K compared to teak and natural forest but organic matter, N and K were greater under eucalypt than in bare soil. No significant difference in soil physical properties, porosity and bulk density was noted in these forest covers. Fertiliser application is needed. Undergrowth is less (particularly in the dry zone); litter is an erosion counter but frequent firing of it causes serious erosion problems. Moisture content is lower in dry zone compared to levels in teak or natural forest. Lower levels of fauna exist in eucalypts. Concern is voiced in environmental degradation with allegations of adverse effects on: soil, hydrology and habitat. Abstracts of local eucalypt research are included.

Key words: Eucalyptus, Sri Lanka, plantations, understory, wildlife habitat, environment.

INTRODUCTION

The Island of Sri Lanka has a land area of about 6.5 million ha Topographically, the country is characterized by two divisions, a highland area in the central part of the island (upcountry) which rises to about 2,500 m and the lowland plains surrounding it. The climate is tropical and maritime. The rainfall is characterized by the southwest monsoon during May-September and the northeast monsoon during October-January. Three major ecological zones are distinguished, based on rainfall patterns: the Wet Zone (over 2,500 mm/year), the Intermediate Zone (2,000-2,500 mm/year) and the Dry Zone (less than 2,000 mm.year). Mean annual temperatures vary from about 28oC in the lowlands to 18oC at the altitude of 2,000 m. Generally, altitudinal range in the upcountry varies from 1,000 m to 2,500 m

The forest land area of Sri Lanka has been shrinking over the last several decades, primarily due to the clearing of forest land for agriculture development and shifting cultivation. According to the GOSL/UNDP/FAO forest inventory based on the aerial survey carried out in 1983, the total forest land in Sri Lanka including scrubland, occupied about 2.45 million ha, or 37% of the total land area of the country. But the dense natural forest cover was 1.75 million ha which represented around 27% of the land area. The forest plantations occupied 1% of the total land area. According to the most recent national forest map prepared by the Forest Department which was based on the satellite imagery of 1991-92, the closed canopy forest cover was only 20.3% of the land area of the country.

The Government of Sri Lanka is deeply concerned about the rapid depletion of forest cover and a Master Plan for the Forestry Sector and a 5 year investment programme was prepared in 1987. The Forestry Sector Development Project which was based on the five year investment programme commenced in 1990 with financial assistance from several of donors. This will be implemented until 1995 and includes the components in forest management, plantation establishment, education and training, forestry research, environmental management and institutional strengthening. In addition to these components a participatory forestry project is scheduled to be implemented from 1994.

HISTORICAL BACKGROUND OF EUCALYPTUS

Eucalyptus were introduced to Sri Lanka in the latter part of 18th century by planters who had links with Australia. Some of these introductions have been very successful as attested by many magnificent trees in and around tea estate gardens in Uva and Dimbulla. A more organized attempt was made by the Botanic Gardens staff who obtained seeds of 50 species in 1880 and most of these were sent to Hakgala Botanical Gardens where a plantation was formed in 1882. Some 20 of these species are still represented today in this garden and have reached enormous size. In 1931, the Forest Department took a hand by laying down seven series of arboretum plots to test the performance of Eucalyptus, Acacia, Araucaria and Cuppressus under plantation conditions in the grasslands of Uva and Nuwara Eliya. These plots ranged from 1,210-1,970 m (4,000-4,500 feet) in altitude and 1,270-2,285 mm (50-90 inches) rainfall. The plot at 1,970 m (6,500 feet) at Kandapola is of particular interest showing rapid growth and remarkably cylindrical stems in the case of Eucalyptus maidenii, E. microcorys, E. pilularis, E. regnans, E. saligna, E. umbellata (syn, tereticornis) and E. robusta. At the altitude 1,210 m (4,000 feet) the best performance have been E. camaldulensis, E. citriodora and E. maculata. E. saligna, E. microcorys, E. pilularis and E. robusta have shown a continued success in this altitudinal range (Warthington et al., 1953).

Reforestation with eucalypts in Sri Lanka has a long and important history. Eucalypts were among the first of three exotics introduced early this century to be raised as a forest plantation species. The other two were teak (Tectona grandis) and mahogany (Swietenia macrophylla) which was introduced little earlier than eucalypt. Eucalyptus species were originally raised in the upcountry to produce fuelwood for households and tea industry. But later most of these species were found very promising for "railway sleepers" and industrial timber. Afforestation of the patana grasslands in the upcountry began in 1930's with planting of E. grandis, E. microcorys and E. robusta in compact blocks on the crests of ridges and hill tops as windbreaks in some places within the Uva Basin. These windbreaks have produced encouraging results by protecting the villages from desiccating winds frequently reaching the area and, improving the living conditions of the people. In 1954 the Forest Department extended this activity of planting windbreaks, mainly with eucalypts, to several other places in the Uva Basin which produced remarkable results within 10 years. One such village known as Palugama, meaning "desolated village" is no longer considered a desolate village and the name has been changed to Keppetipola.

In the 1950's some eucalypts as Eucalyptus camaldulensis, and Eucalyptus tereticornis were introduced to the lowlands of the Wet and Dry zones. Since the 1950's teak reforestation was carried out in the dry and intermediate zones under the "Taungya System". This practice of teak reforestation came to an end in 1970's as only shifting cultivation lands were used for this system, and teak there showed very unsatisfactory results. Only Eucalyptus camaldulensis and E. tereticornis were found successful in these lands. The majority of the eucalypt reforestation in the dry and intermediate zones since the late 1970's were raised under "Taungya system".

PRESENT SITUATION OF EUCALYPTUS IN SRI LANKA

Planting objectives

Eucalyptus are planted to meet the following requirements: a) sawn timber; b) railway sleepers; c) transmission poles; d) fuelwood; e) extraction of essential oils; and f) paper pulp. Eucalyptus are also planted as windbreaks and shelter belts in certain locations particularly in the upcountry. Beekeeping is another common practice in some areas where eucalypt plantations are raised.

Areas planted

Eucalypt species are planted throughout the country. The total extent of eucalypt plantations raised in various parts of the country to 1991 amounts to 29,600 ha (Figure 1). According to mean annual rainfall and the altitude, the planting areas can be categorized in to three agro-climatic regions, i.e. Dry and Intermediate zone, Wet zone and upcountry.

Figure 1. Distribution of Eucalyptus plantations in Sri Lanka

Species

Dry and Intermediate Zone (ha)

Wet Zone (ha)

Upcountry (ha)

Total (ha)

E. urophylla

23

-

-

23

E. camaldulensis

14,976

664

-

15,640

E. robusta

485

4

1,033

1,522

E. grandis

42

62

2,629

2,733

E. torelliana

-

-

30

30

E. tereticornis

840

9

440

1,285

E. pilularis

-

-

34

34

E. citriodora

163

-

114

277

E. globulus

-

-

80

80

E. microcorys

-

-

405

405

Eucalyptus (mixed)

3,038

-

2,987

6,025

Euca/Acacia/

794

30

741

1,565

Cypress/Teak





Total

20,361

765

8,493

29,619

Planting in the Dry and Intermediate zones

Some 20,300 ha of eucalypt plantations were raised in the Dry and Intermediate zones up to end of 1991. The main species are Eucalyptus camaldulensis and E. tereticornis. Small areas of E. citriodora, E. grandis and E. urophylla have been planted in some Intermediate zone areas. Originally, eucalypt planting in this region started with E. camaldulensis for fuelwood but it was replaced by E. tereticornis in late 1980's. E. tereticornis has a better stem form and therefore more suitable for small wood and fuelwood than E. camaldulensis. Due to this reason, and ability to withstand harsh conditions, more E. tereticornis has been grown in recent planting programmes.

The establishment of eucalypt plantations in the Dry and Intermediate zones occurs under several programmes implemented by the Forest Department. These are:

Planting in the Wet Zone

The area of eucalypt plantations in the wet zone to 1991 is 760 ha. The main species are E. grandis and E. camaldulensis. Plantations are confined to two Districts - Kegalle and Galle - where E. grandis is planted in the relatively higher elevations, 500-800 m and E. camaldulensis in the transitional area close to the Intermediate zone. Planting was made under the following programmes:

Planting in the upcountry

Upcountry eucalypt plantations began in the 1930's with establishment of E. grandis, E. microcorys and E. robusta stands in several locations. Establishment was confined to Patana grasslands, denuded and degraded lands. The practice of clearing natural forests for forest plantation establishment was not adopted in the upcountry in past decades. The grasslands fall into two clearly recognizable types, "wet" and "dry", depending on the rainfall. Original vegetation is Cymbopogon confertiflorus and Themeda tremula in the dry, and Chrysopogon-Pollinia-Arundinella in the wet patanas. Apart from the patana grasslands, other lands used for plantation establishment in this region are degraded tropical montane and sub-montane forests. The Forest Department has been very successful in raising large areas of eucalypt plantations on these upcountry lands. Its plantations to end 1991 are 8,490 ha. Main species are E.grandis, E. microcorys, E. robusta, E. pilularis and E. torelliana. Small areas E. citriodora, E.globulus and E. paniculata are present. Generally all eucalypts grow very well with good stem form. Considerable areas of eucalypts are also raised by the estate sector, mainly for fuelwood for tea factories. Eucalypt plantations in this region are raised under these programmes:

ESTABLISHMENT TECHNIQUES

Nursery practices

Seed beds: At present, seed of all eucalypts species grown in Sri Lanka are available locally. Originally most seed was obtained from Canberra, Australia and some E. tereticornis from India. Seed are sown in nursery beds 3 x 1 m raised 15 cm above ground level. The sides of the beds are supported by wooden poles. Bed soil is friable, porous, light textured with a moderate amount of organic matter allowing adequate drainage. The nursery beds are levelled, and 25-50 gm of seed mixed with an equal quantity of fine sand is broadcast sown per bed, and covered with a thin layer of fine sand. Beds are watered with a watering can fitted with a fine rose. Beds are normally covered with bamboo slats during day time until seedlings attain 5-6 cm when they are suitable for pricking out.

Transplanting: Seedlings are container raised and pricked out into 22 x 10 cm (9 x 4" 300 gauge) clear polythene bags with perforations at the bottom. Potting mixture used for filling bags consists of 7 parts of soil, 2 parts of fine sand and 1 part of compost or organic manure. Seedlings 5-6 cm high are pricked out and shade provided in the initial stages. Watering is done regularly.

Age and size of plants: Normal planting size seedling is 30-35 cm, 4-5 months after pricking out. E. deglupta seedlings require 8-9 months to reach this size.

Pest and diseases: Very few pest and disease problems have been reported at the nursery stage of eucalypt. Incidence of cutworm is fairly common in seed beds and is controlled by application of insecticides as Carbofuran. The other common problem is "Damping off" which can be controlled by spraying fungicides as Copper oxide, Antracol or Captan.

Plantation establishment

Land preparation: In the Dry, Intermediate and the Wet zones degraded natural vegetation or scrub jungle is cleared and the debris burnt prior to planting. In the upcountry patana grasslands, mana grass (Cymbopogon confertiflorus) is removed and placed along the contours prior to planting. In hilly terrain the planting lines run parallel to the contour. About a month before planting, the area is aligned and marked with a small patch, about 1 m diameter, and clean weeded around the planting hole. Planting holes 25 cm in diameter and 45 cm deep are dug with the help of crowbars and other implements.

Time of planting: In the Dry, Intermediate and in the drier parts of the upcountry zones, planting is done once a year with the North-East monsoonal rains in October-December. In the wet zone and high rainfall areas in the upcountry, planting is usually done twice a year during the South-West (May-July) and North-East (October-December) monsoonal rains.

Spacing: Spacing of 2.5 x 2.5 m is used for all species planted in the upcountry and Wet zone with an exception for E. camaldulensis. E. camaldulensis in the wet zone and all eucalypts species planted in the Dry and Intermediate zones are planted at a spacing of 2 x 2 m for maximum biomass production. When eucalypt species are mixed with other species such as teak (Tectona grandis) in the dry zone and cypress in the upcountry, the usual spacing adopted is 2.5 x 2.5 m. When eucalypts are mixed with Acacia auriculiformis in the dry and intermediate zones, the spacing remains as 2 x 2 m because both species are grown as short rotation fuelwood crops. In the Dry zone, when eucalypt is planted under the "Taungya" system, the espacement adopted is 2.5 x 2.5 m due to inter-row cultivation of food crops.

Fertilizer application: Fertilizers were not generally used in forest plantations in early days. At present, sites available for reforestation are generally poor in nutrient status, fertilizer application is required for better growth of seedlings; 50 gm of NPK (15:15:15) fertilizer are applied to the soil at the time of planting and to 2 year old plants.

Tending and filling of vacancies: During the first year, the areas are patch or circle weeded (1 m radius) manually and in areas where weed growth is heavy (generally Wet zone, Dry and Intermediate zones) low slashing, or strip weeding, is carried out along with patch weeding. The frequency of weeding depends on the area and the amount of weed growth, but on an average 3 weedings are done during the first year, 2 weedings in the second year, and a single weeding (low slashing) is done during the third year. Vacancies are filled during the first year. The use of herbicides and raising of irrigated plantations are not practised.

Pest and diseases: Incidence of termite attack is common in eucalypt plantations in the Dry zone, but is relatively low in the Wet zone. Termite attack is not a significant problem in the upcountry wet areas, but in the drier areas of this region the problem is observed in significant levels. Among eucalypts species planted in the Dry and Intermediate zones E. camaldulensis is the most susceptible to termite attack. Susceptibility of E. tereticornis is relatively low compared to E. camaldulensis. In the upcountry drier areas, termite attack has been reported both in E. tereticornis and E. camaldulensis plantations. E. grandis also shows a susceptibility when planted in the Intermediate and drier areas in the upcountry. Depending on the intensity of the termite attack insecticides are applied either at the time of planting or when the attack is observed. Generally, when the incidence of attack is high, soil in the polythene tubes is dipped in a 0.5%. Aldrin solution before planting. This has been an effective method in controlling termite attack until the seedlings are established in the field.

To date no other pest attack or disease has been observed. Damage by cattle and porcupine has been observed particularly in the Dry and Intermediate zones and drier parts of the upcountry. In some areas in the upcountry grasslands, stray cases of cankerous growth and gummosis have been observed and this eventually leads to gradual death of affected trees.

Fire hazard: Fire is a source of danger to eucalypt plantations specially in the Dry zone and upcountry grasslands. Plantations are provided with a network of internal and external fire lines. The external fire lines are 10 m wide and internal fire lines are 5 m wide. Fire watchers are employed during the fire season in vulnerable areas.

Thinning regimes: Where practised, generally 20% to 30% of the basal area is removed depending on the performance of the crop. With pulp and fuelwood crops, no thinning is done; in timber crops, the 1st thinning is in 7th year, 2nd in 13th and the 3rd in the 18th year.

MANAGEMENT - ROTATION

The only management operation carried out in eucalypt plantations other than thinning and weeding is creeper cutting and cleaning. Generally, this is done in 1-2 year intervals as and when it is required. The rotation age of eucalypt species depend on their management objectives. Since the demand for eucalypts for pulp is very limited in Sri Lanka, pulp wood production is not a major objective in eucalypt planting. E. camaldulensis and E. tereticornis are managed for small timber and fuelwood with a 7 year rotation age. The regeneration of the 2nd and 3rd crop is through coppice, after which artificial regeneration is adopted to raise the new crop. All other eucalypts species planted are managed primarily for production of transmission poles and sawn timber including railway sleepers. Production of fuelwood is considered as a secondary product from these plantations. Rotation ages of the plantations are: fuel and pulp wood, seven years; transmission poles fifteen years; timber twenty five years.

UTILISATION OF EUCALYPTUS

Fuelwood: Eucalyptus species grown under short rotations (7 years) with closer spacing (2 x 2 m) are generally used for production of firewood. These are E. camaldulensis and E. tereticornis. Fuelwood is produced as a secondary product from other species which are grown under long rotations.

Small timber: Timber, as fence posts and other small round timber, is produced from short rotation crops and as a secondary product from long rotation crops. This includes products from thinnings and as secondary products of the final harvest.

Transmission poles: These poles are produced from medium rotation (15 years) crops grown mainly in the upcountry and wet zone. Generally, E. grandis, E. microcorys and E. robusta, are used for production of transmission poles. Since the wood of E. grandis has a tendency to split, is always used with gang nails fixed on to transmission poles.

Railway sleepers: E. grandis, E. microcorys, E. robusta and all other eucalypt species grown in the upcountry as long rotation crops are converted to railway sleepers. E. grandis is used for this purpose with gang nails.

Sawn timber: E. microcorys, E. robusta and E. torelliana are the main species used for production of sawn timber for constructional purposes. These species are grown in the upcountry as long rotation industrial plantations for production objectives as sawn timber. Eucalypts contribute about 18% of the total industrial wood production from forest plantations.

Essential oils: At present only leaves of E.globulus are used for extraction of essential oils. Distilling is done by villagers living around forest plantations as a cottage industry, but this activity is confined to several villages only in Badulla district in the upcountry.

Beekeeping: Generally, eucalypt species produce large quantities of nectar and pollen which supply the food required for honey bee colonies. Quality and quantity of nectar and pollen depend upon the species. Beekeeping is a common practice in several villages located near eucalypt plantations at Bandarawela in the upcountry, but at present this activity is confined to these isolated locations only.

Pulp and paper manufacture: E. grandis is used for making paper pulp in Sri Lanka. The demand for eucalypt for pulping is very limited due to various constraints in the paper pulp industry. Paper making is still not a major use of eucalypt in Sri Lanka.

Production of charcoal: E. camaldulensis and E. tereticornis are used in small quantities for production of charcoal. Production of charcoal is limited in Sri Lanka due to it's low domestic use demand.

ECOLOGICAL ASPECTS OF EUCALYPTUS PLANTATIONS

Growing of eucalypts and other exotic species as tropical pine in Sri Lanka has aroused strong contra feelings among some environmental groups. Opposition to eucalypts centers on ecological degradation, attributed to the establishment of large areas of plantations. Areas of main concern are: likely adverse effects on soil fertility, hydrology and biodiversity.

Impact on soil

Soil nutrient: There is an important difference between the soil nutrient status of a natural forest and that of forest plantations particularly when the plantations are grown on short rotations. In a natural forest, the disturbance to the nutrient cycle is minimal and the nutrients are conserved and cycled between the trees and the soil. When the forest plantation is thinned or felled and the wood is extracted, the nutrient content in the system changes considerably due to removal of nutrients from the site. The type of wood produced from eucalypt plantations may be fuelwood, poles, paper pulp or sawn timber depending on the rotation and the nutrients in these products are removed from the site within a comparatively short period of time. Generally, short rotation crops reduce the nutrient status of the soil faster than medium and long rotation crops.

According to a study of the effect of E. camaldulensis on fertility status of the soils in the Dry zone of Sri Lanka this showed that soils under 14 year old E. camaldulensis plantation had lower organic matter content than in the soils under similar aged Tectona grandis plantation and natural forest (Ranasinghe and Jayasuriya, 1991). Further, available potassium and total nitrogen under eucalypt were significantly less than that of under teak and natural forest. But organic matter, available potassium and total nitrogen were greater under E. camaldulensis than these under bare soil. Although this nutrient depletion was observed under eucalypt, there was no significant difference in soil physical properties, mainly porosity and bulk density under the three vegetation types.

Nutrients are found in every part of the tree in different proportions, and biomass or dry matter production is used to measure the amount of nutrients removed by the crop. A study carried out to investigate the biomass production and it's distribution in an age series (2-14 years) of E. camaldulensis plantations in the dry zone of Sri lanka reported a total dry biomass production of 163 ton/ha at the age of 14 years. This is generally high when compared with slow growing natural vegetation. Eucalyptus are widely used in the dry zone of Sri Lanka for the afforestation of degraded scrub jungles which have been subjected to shifting cultivation. E. camaldulensis and E. tereticornis are grown in the dry zone for production of fuelwood and small timber such as poles and higher levels of biomass utilization is expected from these short rotation crops. Whole tree harvesting and shortening of the rotation period increase the rate of nutrient removal from the soil.

This is evident from the results reported by Wise and Pitman (1981) quoting Poore and Fries (1985). They reported that the nutrient removal under natural sawlog regime of a native forest in New South Wales was less than 5% of that removed in total tree utilization in short rotation eucalypt plantations. This rapid depletion of nutrient reserves in the soil by eucalypts has been confirmed by the above study (Ranasinghe, 1991) and this is a direct consequence of fast growth rate and management for whole biomass utilization as a short rotation crop. This would apply the same way to any other highly productive crops under a similar rotation. Application of fertilizer is necessary to overcome the nutrient depletion of the soil specially when eucalypt is grown as a short rotation crop.

In a study carried out in the Dry zone, it was observed that the soil under Eucalyptus camaldulensis tend to become slightly acidic with the increase in depth (Ranasinghe and Jayasuriya, 1991). This was more prominent at depths 46-60 cm, 61-40 cm and 81-100 cm.

Soil erosion: Scientific evidence is not available from Sri Lanka on this subject. However, observations made in short and long rotation eucalypt plantations confirm findings reported from many other countries (Poore and Fries, 1985) and Shiva and Bandyopadliyay (1985). According to observations made in the Dry zone and upcountry Eucalyptus plantations after about 10 years of age, the growth of understory vegetation is reduced and in most of the older plantations very little or no under story vegetation exists to prevent rain drop impact and surface run off. This effect is somewhat compensated by the accumulation of litter under eucalypt plantations. The litter fall in E. camaldulensis plantations in the dry zone has been reported as 1.7 times than that of the natural forest in the same area whilst the decomposition rate of both remains the same (Ranasinghe and Jayasuriya, 1991). Frequent burning of litter due to fire hazard is very common in most plantations causing series soil erosion problems. Prevention of fire damage is very important in eucalypt plantations to reduce surface run off and soil erosion. Further, at seedling stage, eucalypts are susceptible to weed competition and therefore the strip weeding adopted in steep terrain also cause certain amount of soil erosion.

Impact on water: Studies on the impact of eucalypt plantations on water resources are yet to be carried out in Sri Lanka. However, it has been established that catchments under forest vegetation have a lower water yield than those under scrub or grasslands, but they may regulate the stream flow better, depending upon the characteristics of the forest vegetation. The important characteristics affecting this are: ground cover, growth rate, addition of organic matter to the soil, nature of the surface root system etc. However, observations made in the dry zone of Sri Lanka, showed lower moisture content in the lower soil layers under E. camaldulensis than teak and natural forest. This could be attributed to the absorption of moisture from lower horizons due to greater moisture requirements of eucalypts.

Impact on biodiversity: Monoculture plantations of exotic tree species are poor in under-story floristic composition. According to the observations made in many eucalypt plantations in Sri Lanka, including dry and wet zones and upcountry, after about 10 years of age, the growth of understory vegetation is reduced. This is very significant in older plantations throughout the country with little or no undergrowth even in the high rainfall areas such as wet zone and wetter parts of the upcountry. This effect of eucalypts on understory vegetation does not show a significant variation due to species, but the climate, particularly the rainfall, shows some recognizable impact on the understory vegetation. Older plantations in the dry zone and in the drier parts of the upcountry show extreme cases without any vegetation under these stands. The factors are popularly attributed to poor floristic composition under eucalypts are: competition for water; allopathic effects; low light intensity (this is probably less than those caused by most of other broad leaved trees) and increased competition for nutrients. The most significant factor may be the competition for water. However, understory vegetation has a very significant impact on soil erosion, as when it is greatly reduced, the area becomes prone to erosion.

Quantitative information is not available on the effect of eucalypts on fauna. However, it has been noticed that, numbers and diversity of mammals, birds and insects in eucalypts plantations are much less than in floristically more diverse natural forests.

ECONOMIC AND SOCIAL ASPECTS OF EUCALYPTUS PLANTATIONS

Social aspects

Sri Lanka is no exception in this regard and, as in many other countries, eucalypt planting has become the subject for argument because of ecological and social considerations. Eucalypt plantations are raised mainly by the Forest Department to meet country timber and fuelwood requirements. Apart from the ecological aspects, the main criticism against eucalypt planting is that it does not provide any food value either to the local people or browsing animals as fodder. But the advantage is that it provides fuelwood and timber to the local people within a short period of time.

However, under the Community Forestry Project implemented by the Forest Department from 1982-89, introduced E. grandis, E. microcorys, E. robusta and E. torelliana for planting by the local people under an agroforestry programme in farmer's woodlots. Eucalypt species were among the main species identified for this agroforestry programme to produce fuelwood and timber requirements of the local people. Other tree species included in the programme were food, fruit and fodder trees. The land was provided to the farmers on long term leases and food aid was provided to compensate for their labour. This programme was successfully completed by the Forest Department in 1989, and 1,260 ha of agroforestry woodlots were established with eucalypt as one of the main species. The local people prefer to plant eucalypt as a timber species along with other tree species to produce food, fruit and fodder. Therefore, the scope of eucalypts in social or Community forestry programmes is limited.

Economic aspects

Eucalypt plantations in the wet zone and upcountry are managed for timber production while dry zone plantations are managed for small timber and fuelwood. Establishment and maintenance costs are shown in Figure 2. Details of cost and benefits along with the IRR for a 25 year rotation for 3 climatic regions are given in Figure 3 (3 coppice rotations are included in fuel wood and pulp wood crops). Land value is not included in the analysis as plantations are established on State lands.

GOVERNMENT POLICIES AND PROGRAMMES ON EUCALYPTUS PLANTING

Government policies on planting Eucalyptus

The main objectives of the reforestation programmes are to meet: a) the industrial wood and fuelwood requirement of the country: and b) the environmental protection requirements. (Eucalyptus does not come under this category).

Eucalyptus has been identified as one of the major trees for the Department of Forests reforestation programmes to produce timber and fuelwood for the country. This is due to rapid growth and the adaptability to a wide range of site and climate conditions. Generally areas available for reforestation are poor sites and very difficult to establish most of the tree species. However, eucalypts have good timber and fuelwood production potential in such sites and species have been identified to plant in all the climate regions in the country. About 20% of the forest plantations established by the Forest Department in the past were various species of eucalypts.

The alternative strategies implemented in the industrial and fuelwood reforestation are:

Figure 2. Cost of establishment and maintenance

Activity

Upcountry

Scrublands

Wet zone

Dry Zone

25 year Rotation (SL Rs.)

25 year Rotation (SL Rs.)

7 year Rotation (SL Rs.)

Year 0




Cost of planting




Materials

3,825

3,825

6,200

Site preparation

6,800

6,100

8,600

Outplanting

1,500

1,050

1,700

Fertilizing

1,000

1,000

1,540

Fire prevention

2,500

2,500

2,500


15,625

14,475

20,540

20% Overhead

3,125

2,895

4,108


18,750

17,370

24,648

Year 1




Beating up gaps

500

400

600

Fertilizing

1,000

1,000

1,540

Fire prevention

1,700

1,700

1,700

Weeding

9,000

9,000

11,000


12,200

12,100

14,840

Year 2




Fire prevention

1,700

1,700

1,700

Weeding

6000

6,000

7,200


7,700

7,700

8,900

Year 3




Fire prevention

1,700

1,700

1,700

Weeding

3,000

3,000

3,600


4,700

4,700

5,300

Total cost (for first 4 year period)

43,350

41,870

53,688

Figure 3. Cost/benefit analysis of Eucalyptus plantations (SL Rs)

Stand Age

Operation

Grasslands Upcountry

Scrublands

Wet zone

Dry zone

1

Establishment

-18,750

-17,370

-24,648

2

Weeding

-12,200

-12,100

-14,840

3

Weeding

-7,700

-7,700

-8,900

4

Weeding

-4,700

-4,700

-5,300

5-6

Protection

-1,000

-1,000

-1,000

7

1st thinning

18,720

15,600

11,700

8-12

Protection

-1,000

-1,000

-1,000

13

2nd thinning

62,920

72,600

60,500

14-17

Protection

-1,000

-1,000

-1,000

18

3rd thinning

144,650

183,950

118,350

19-24

Protection

-1,500

-1,500

-1,500

25

Final felling

981,000

1,305,900

793,200

IRR


18.4%

20%

15.4%

The proposed reforestation programme in the Forestry Master Plan includes establishment of 42,000 ha of new industrial timber plantations and 27,000 ha block fuelwood plantations during the period 1985-2000. The proportion of eucalypt in the present industrial wood and fuelwood planting programme is considerably high. In the upcountry this comes to about 25-30% of the total reforestation and in the dry zone about 7-8%. The main species recommended for the upcountry are E. microcorys, E. pilularis and E. grandis. The species recommended for the dry zone are E. tereticornis and E. camaldulensis. The scope of eucalypts in community wood lots, farmer's wood lots and extension planting programmes is limited due to the preference of other species such as food and fruit trees.

Present programmes on Eucalyptus planting

Forestry Sector Plan: Reforestation programmes under the Forestry Sector Development Project forms the major reforestation activities in the country at present. Apart from this there are few other reforestation programmes under Integrated Rural Development Projects. These programmes include establishment of industrial wood and fuelwood plantations and establishment of protective plantations. As indicated in the earlier section eucalypt species play a significant role in these industrial wood and fuelwood planting programmes. Extent of eucalypts planted during the last ten years (1983-92) are given in Figure 4.

Figure 4. Extent of Eucalyptus species planted during the last ten years in Sri Lanka (ha)

Year

Total

Eucalyptus planting

Eucalyptus as a%

1983

7,976

5,154

65

1984

7,641

4,667

61

1985

6,292

3,147

50

1986

4,864

2,326

48

1987

5,032

1,839

37

1988

3,750

573

15

1989

5,779

1,623

28

1990

2,613

194

07

1991

3,885

438

11

1992

3,495

379

11

Prior to 1980 eucalypt planting contributed about 20% to the total reforestation programme of the Forest Department. After 1980 the proportion of eucalypt planting was increased considerably due to commencement of 2 fuelwood planting projects, namely fuelwood planting component of the Reforestation and Watershed Management Project (1981) and block fuel wood planting of the Community Forestry Project (1982). Eucalypt was the major fuelwood tree identified under both programmes. The planting under earlier project was confined to the North-Western, North-Eastern and North-Central parts of the Dry zone and the other programmes was mainly concentrated in the upcountry. The Reforestation and Watershed Management Project was completed in 1987 and the Community Forestry Project completed in 1989. A marked increase in eucalypt planting during the period 1980-89 can be seen. (Figure 4 shows data only from 1983-92). At present no special fuelwood projects are activated, but the normal reforestation programme of the Forest Department under the Forestry Sector Development Project includes eucalypt planting for industrial timber and fuelwood production. The main eucalypt species planted in the upcountry are, E. microcorys, E. grandis, and E. pilularis. The main species in the Dry zone and Intermediate zones are E. tereticornis and E. camaldulensis.

The eucalypt plantations are being established by using different methods of plantations establishment. Some of these are: a) Forest Department direct planting; b) Taungya system (Corporative Reforestation); c) Farmer's wood lots; and d) Fuelwood planting by tile, brick and ceramic industry.

The total reforestation programme at present is around 4,000 ha per year and eucalypt reforestation covers 10-15% of the total reforestation or 400-500 ha annually. The participatory Forestry Project funded by ADB is scheduled to be implemented from 1994-98. The species selection under this programme will be made at the time of implementation, in consultation with participants.

NGO's and private sector involvement.

NGOs: Many non-governmental organizations (NGOs) are giving increased attention to environmental issues particularly deforestation and reforestation in Sri Lanka. NGO's both at National and local level are concerned about environmental conservation, and the participation of rural people in these programmes. The forestry activities of NGO's in Sri Lanka include the following:

However, in general NGO's do not support planting of exotic tree species particularly eucalypt and tropical pine in Sri lanka. Eucalypt has been introduced and grown in Sri Lanka by early foresters due to its rapid growth and adaptability to a wide range of site conditions. Although these plantations now produce large quantities timber and fuel wood, these plantings are being strongly criticised in some quarters, including NGO's, because they are alleged to cause adverse effects on soil, hydrology and they provide a relatively poor habitat for wildlife. Due to these arguments against eucalypt planting, NGO's normally do not get involved in planting these species under their tree planting and social forestry programmes. Generally they prefer indigenous tree species over any exotic species for their programmes.

Private sector: The Forest Department is promoting Private Sector investment in reforestation. Under a special scheme initiated in 1980 to interest private sector involvement in reforestation; degraded and shifting cultivated lands were leased to prospective investors in the Dry and Intermediate zones on a long term basis to raise fast growing timber and fuel wood species.

A successful reforestation programme with eucalypt under this scheme was implemented with the participation of the Ceylon Tobacco Company (a private company). Ceylon Tobacco company (CTC) requires fuelwood for curing their tobacco leaf. It has been estimated that 20 m3 of fuelwood is required to produce 1 metric ton of cured tobacco by the Company. To meet this fuelwood requirement the CTC embarked on a systematic afforestation programme in the 1980's. To date the Company has established about 500 ha of eucalypt plantations. The main species are: E. grandis, E. tereticornis and E. camaldulensis. In addition, the Company fostered tobacco farmers to plant eucalypts for Company fuel wood requirements. Tobacco farmers are supplied with seedlings of eucalypt by the CTC to plant in their farms. These seedling are planted along the boundary of the farms by farmers and the harvest is purchased by the Company.

Further degraded and shifting cultivated forest areas in the dry zone are released to Sri Lanka Ceramics Corporation and private brick and tile industries to obtain their fuelwood requirements and replant with fast growing fuel wood species. E. tereticornis and E. camaldulensis are planted under this programme along with Acacia auriculiformis. This programme is implemented by the Forest Department every year to plant fuelwood species with the participation of private sector and other agencies.

REFERENCES

Anon.1986. Forestry Master Plan for Sri Lanka 1986. Annex I -Forest Resources and Forest management.

Anon.1986. Forestry Master Plan for Sri Lanka. (1986) Annex III - Silviculture.

Anon.1991. Administration Report of the Conservator of Forests, Sri Lanka for the year 1991.

Poore, M.E.D., Fries, C. 1985. The ecological effects of Eucalyptus. FAO Forestry paper 59, Rome, 1985.

Pryor, L.D. 1964. Report on afforestation with Eucalyptus in Sri Lanka. Sri Lanka Forester. Vol; VI. 3 & 4, 95-100.

Ranasinghe, D.M.S.H.K. 1989. Distribution of nutrients in an age series of E. camaldulensis plantations in the dry zone of Sri Lanka. Sri Lanka Forester 19: 1-4, 53-5.

Ranasinghe, D.M.S.H.K. et al. 1991. Dry matter content and it's distribution is an age series of E. camaldulensis plantations in Sri Lanka. Forest Ecology & Management 41: 137-142.

Ranasinghe, D.M.S.H.K. and Jayasuriya A.W.A.1991. An investigation in to the effect of monocultural plantations of Eucalyptus camaldulensis on soil fertility status. Vidyodaya Journal of Science 3: 115-127.

Ranasinghe, D.M.S.H.K. et al. 1992. Effect of Eucalyptus litter on germination and initial establishment of neighbouring plants. Proceedings of 48th annual sessions of Sri Lanka Association of Advancement of Science. (SLAS).

Ranasinghe, D.M.S.H.K. et al. 1992. Ground flora in different aged Eucalyptus and Acacia plantations. Proceedings of 48th annual sessions of SLAS.

Ranatunga, M.S. 1972. Notes on the planting of forest species, Sri Lanka Forester. Vol. 10: 3 & 4, 103-116.

Tissawerasinge, A.E.K. 1987. A brief note on the history of Eucalyptus plantations in Sri Lanka. Sri Lanka Forester. Vol 18: 1-2, 44-45.

Worthington T.B. et al. 1953. Notes on Eucalyptus in Sri Lanka. Sri Lanka Forester Vol I: 1 & 4, 112-122.

ANNEX

STATUS OF SOME RESEARCH ACTIVITIES PERTAINING TO EUCALYPTUS IN SRI LANKA

Arulchelvum, K. 1971. Variation of fibre length and density in Eucalyptus robusta grown in Sri Lanka. Sri Lanka Forester 10: 1-4, 19-32.

Variation in fibre length and density was studied in five specimens of Eucalyptus robusta from an even - aged plantation in Sri Lanka. There is a steady increase in fibre length the pith up to 3 cm form the pith. This increase is determined mainly by the elongation of the fibres. Beyond this point the increase in the length is determined by the length of fusiform initial (indicated by the length of vessel member) rather than elongation; The maximum fibre length is not achieved until the tree reaches a diameter of approximately 19 to 22 cm or an average age of 9 years. There is a low density core of 6 cm diameter outside which the density rises steadily.

Fernando, M.J.J. 1989. The tolerance of some eucalypts to salinity, as determine by germination and seedling growth. Sri Lanka Forester 19: 1-4, 17-30.

Solutions of NCAL at various concentrations were used to treat Eucalyptus camaldulensis, E. tereticornis and E. citriodora at germination and as container - grown seedlings. Germination percentage, rate of germination, survival, height growth, root length, root dry matter ratio were assessed, and seedling injuries were also observed. E. camaldulensis was found to be the most salt tolerant, E. tereticornis moderately tolerant, and E.citriodora the most sensitive.

Fernando, M.P.A.U.S. et al. 1980. Analysis of fuelwood in plantations in Sri lanka. Sri lanka Forester 16: 1-4, 11-17.

Rotation ages for eucalypt plantations were set at 36 years - the culmination of mean annual increment - for the original plantation and 2 coppice crops. Economic criteria should also be considered in establishing rotation ages. This article presence the results of a study on the financial and economic returns to establishing eucalypt plantations in Sri Lanka.

Gunawardene, W.E.S. 1953. The control of Lantana in a plantation of Eucalyptus species. Sri lanka Forester 1: 2, 4, 123-124.

The results of these trails indicate that beating down and burning is the most effective of the methods tried in the control of lantana. Adequate control of the five prevented damage to the over wood, cutting lantana low and poisoning the stumps with sodium arsenite was effective but is more expensive and difficult of execution. Lantana was killed off more effectively by Fernosone solution (20 lbs. in 40 and 80 acre) than by Sodium chlorate (40) gallons per acre).

Jayasuriya, A.W.A. et al. (1990). A comparative study on litter fall and nutrient status in Eucalyptus camaldulensis monoculture, Tectona grandis monoculture, a natural forest and a bare land. Proceedings of the 46th annual sessions of Sri Lanka Association of Advancement (SLAS) of Science.

Statistically significant differences were observed (P<0.05) in moisture content, PH value percentage organic matter, potassium and calcium contents and cation exchange capacity in soils. Moisture and organic matter percentages were highest in Tectona followed by natural forest, Eucalyptus and then the bare land. Lowest pH value was encountered in soils under eucalypts which was followed by natural forest. The bare land showed the highest. Potassium and Calcium contents showed the orders; natural forest > Tectona > Eucalyptus > bare land and Eucalyptus > Tectona > natural forest > bare land respectively. Cation exchange capacity was highest in the natural forest followed by Tectona, Eucalyptus and bare land.

Kingsely, S.A.D. 1987. The effect of boron on the early growth and survival of Eucalyptus tereticornis and Tectona grandis. M.Sc. Thesis Forestry Project, University of Sri Jayawarde-napura.

There is no statistically significant mean total height growth or mean total height increment due to Boron applications. The survival percent and damage percent between treated and untreated seedlings were statistically significant. There was a positive connection between the amount of boron applied and the foliar Boron correlated to the extent of damage and mortality or negatively correlated to survival percent.

Kulatunga, R.S. 1987. Early performance of selected provenance of Eucalyptus camaldulensis and E. tereticornis in the Dry zone of Sri Lanka. M.Sc. Thesis, Forestry Project, University of Sri Jayawadenapura.

The germination of E. camaldulensis provenance Petford, Katherine and E. tereticornis provenance was greater than 90%. The total height and biomass production of Petford and Katherine were greater. Based on the overall performance the provenance can be recorded as follows. Petford, Katherine, Mysore hybrid, Kennedy river, Petford Katherine.

Medema, E.L. et al. 1985. The determination of financial rotation age for coppicing tree species. Forest Science 31: 23, 398-404.

An analytical method has been described for simultaneously determining optimum harvest age and optimum number of harvests before stand reestablishment given a specific yield function, based on land rent. An example is given of coppicing Eucalyptus camaldulensis in Sri Lanka.

Midgley, S.J. et al. 1986. Termites and their control in Eucalyptus plantations of the community forestry projects in Badulla in Sri Lanka. Sri Lanka Forester 17: 1-4, 111-115.

The method has proved to be very effective with almost no incidence of termite attack being recorded, in 1985 plantings where attack has been recorded invariably the seedlings had been planted too deeply and the termites had moved across the untreated soil "bridge" to attack the seedling. The effectiveness of the technique is further demonstrated by results from the assessment trails where dipping in a 1% W/V solution of Aldrex powder or in solution of Broot (a.i. tremetacarb, also known as Landrin) has not been as promising, probably due to its easy degradation in the soil.

Perera, W.R.H. 1962. Afforesting arid areas in Mannar region of Sri Lanka using the "methode steppique". Sri Lanka Forester 5: 1-4, 195-202.

In the planting areas where no rides were formed, but planting was done on the ploughed land, by the end of five months except for one or two suppressed plants - the rest of the eucalypt has all died. Where planting was done on the ridges the plants thrived extremely well and at the end of 5 months the survival was about 70%. Subsequently, severe drought condition prevailed and the survival came down to 5%.

Perera, K.L.S.D. 1987. Treatability of coconut and eucalypt species by pressure impregnation. M.Sc. Thesis, Forestry Projects, University of Sri Jayawardenapura.

Cocus nucifera and E. grandis wood can be treated with oil for use in effectively by both C.C.A and creosote-furnace oil for use in outside locations. E. pilularis wood was extremely resistant to the pressure impregnation. Likewise E. robusta was resistant to preservative treatment, but retention of creosote-furnace oil was enough for use under exposed conditions not in direct contact with the ground. When treated with C.C.A. additional protection with a coat of paint or varnish at regular intervals is necessary.

Ponnambalam, R. 1967. Notes on timbers. Sri lanka Forester 8: 1-4, 33-35.

The wood of Eucalyptus microcorys has been tested for is mechanical properties such as static bending, cleavage on Radical plane, cleavage on Tangential plane,radical shear parallel to Grain, Tangential shear parallel to Grain and compression parallel to Grain.

Pryor, L.D. 1964. Report on afforestation with eucalypts in Sri Lanka. Sri Lanka Forester 6: 1-4, 95-100.

Recommendations for use of Eucalyptus in Sri Lanka and species performance, future planting in the high lands, prospects for planting in the low lands and establishment of techniques and special trials were discussed in lengths in this article.

Ranasinghe, D.M.S.H.K.1989. Distribution of nutrients in an age series of E. camaldulensis plantations in the Dry zone of Sri Lanka. Sri lanka Forester 19: 1-4, 53-5.

The distribution of nutrients was determined in Eucalyptus camaldulensis ranging in age from two to fourteen years, at two sites in the Dry zone of Sri lanka. There were significant differences in nutrient percentages by tree component, that were unrelated to age or site. There were high nutrient concentrations were leaves and bark the lowest concentrations in the bole (without bark). The mean annual increment peaked at ten years. An estimate is given of the quantity of nutrients that would be removed by complete tree harvesting at age ten.

Ranasinghe, D.M.S.H.K. et al. 1991. An investigation into the effect of monocultural plantations of E. camaldulensis on soil fertility status. Vidyodaya Journal of Science 3: 115-127.

Total litter production of eucalypts in the dry zone was 370.68 kg/ha as compared with 1349.07 kg/ha in Tectona grandis (study period overlapped the leaf senescence) and 217.75 kg/ha in the natural forest. Litter decomposition was 40.22% in eucalypt while it was 40.27% and 44.95% in natural forest, and Tectona respectively. Nutrient release to litter at the time of fall did not differ between the vegetation types. However, it differed between the tree components and nutrients, the orders being leaves>twigs>bark and N>P>K>Ca.

Ranasinghe, D.M.S.H.K. et al. 1991. Dry matter content and it's distribution in an age series of E. camaldulensis plantations in Sri Lanka. Forest Ecology & Management 41: 137-142.

Dry matter production was determined for Eucalyptus camaldulensis aged 2-14 years, planted for energy in Puttalam (annual rainfall 1,100 mm) and Monaragala (annual rainfall 1,588 mm) in Sri Lanka. Total dry biomass ranged up to 163 t.h (Monaragala) and 148 t/ha (Puttalam) at age 14 years, at which point the root system accounted for 5% of the total. The root: shoot ratio declined steadily from a maximum at age 2 of 0.145. Mean annual leaf production per ha peaked between 10 and 12 years on both sites. Mean annual leaf efficiency index was at a maximum of 4.05 at 4 years (top height 9.2 m). Total above ground dry weight could be accurately predicted from mean diameter at breast height.

Ranasinghe, D.M.S.H.K. et al. 1992. Effect of Eucalyptus litter on germination and initial establishment & neighbouring plants. Proceedings of 48th annual session of Sri Lanka Association of Advancement of Science. (SLAS)

A preliminary trial was carried out to test the effect of eucalypt litter on the germination and establishment of other plant species in the neighbourhood. Substrates were prepared with different combinations of soil and ground Eucalyptus camaldulensis litter. Certified seeds of Vigna sesquipedalis spp were sown on these substrates. The mean height and leaf number observed after one month of establishment was highest in the treatment beyond which they declined as the proportion of Eucalyptus grew higher. The lowest was recorded in the treatment containing only eucalypt leaves.

Ranasinghe, D.M.S.H.K. et al. 1992. Ground flora in different aged Eucalyptus and Acacia plantations. Proceedings of 48th annual session of SLAS.

The number of species/unit area (25 m2), total number of trees/unit area (1 m2) and dry weight of ground flora/ha were significantly higher in Eucalyptus camaldulensis the values being 27,264 and 16 as compared with those of Acacia auriculiformis, the values being 19,148 and 13. The area devoid of tree cover had the highest values in all the parameters (28,267 and 27 respectively.)

Ranatunga, M.S. 1964. Study of the Fibre length of E. grandis grown in Sri Lanka. Sri Lanka Forester 6: 1-4, 101-112.

Measurement of vessel element and fibre length was made in four even aged (34 years) plantations grown Eucalyptus grandis trees. Both vessel elements and fibres increased in length outwards from the pith reaching a constant length at about 25% of the radical distance from the pith to the periphery (about 8 years). Fibre lengths at comparable distance from the pith were less at the bottom of the tree. Intrusive growth of fibres was least near the pith. Rapid growth is accompanied by greater intrusive growth of the fibres. Sampling for the selection of plus tress should be from tress more than 9 years of age and is safe at not lower than 10% stem height, though this may be higher than necessary.

Ranatunga, M.S. 1966. Silvicultural problems connected with the growing of Bamboo, Pines and Eucalyptus. Sri Lanka Forester 7: 1-4, 124-129.

At present there are 28 species of Eucalyptus on record and most of which are confined to the up-country, of these the most successful are Eucalyptus grandis, Eucalyptus microcorys and Eucalyptus robusta growth rates of these are higher than any other species growing in Sri Lanka. The annual production of Eucalyptus grandis is in the order of 300 feet3 per acre per annum.

Steimbeck, K. et al.1985. Calorific values of 12 forest tree species grown in Sri Lanka. Sri Lanka Forester 15: 3-4, 136-138.

Wood samples were collected in 1981 from trees which for the most part grew in plantations and sent to USA and analyzed for their calorific content in a bomb calorimeter. The calorific value for stem wood of E. microcorys, E. tereticornis, E. camaldulensis and E. alba are respectively 4,828, 4,788, 4,752 and 4,683 gm calories per gm of wood.

Soyza, A.M.T. 1973. Natural durability of 12 timbers found in Sri Lanka. Sri Lanka Forester 11: 1-4, 24-36.

Battens end (60 cm x 5 cm x 5 cm) of twelve species of timber were tested for their natural durability over a four-year period. The filed tests which are being continued were conducted at three sites (Pattipola, Waga and Anuradhapura). The durability of the timbers was assessed qualitatively in terms of deterioration due to attack by decay fungi and subterranean termites. Of the twelve species of timber tested Shorea zeylanica (Dun), Eucalyptus microcorys (Tallow wood), Calophyllum pulcherimum, (keena sp) showed the highest resistance.

Tait, D.E. 1986. A dynamic programming solution of financial rotation ages for coppicing tree species. Canadian Journal of Forestry Research 16: 4, 799-801.

The optimum policy for the problem of determining of E. camaldulensis optimum harvest age and optimum number of harvests before replanting a coppice of eucalypt is shown to satisfy a simple recursive relationship which may be solved using dynamic programming.

Tissawerasinghe, A.E.K. 1967. Preliminary report on the prevention of splitting in poles of E. grandis using gang nails. Sri Lanka Forester 8: 1-4, 20-32.

An experiment tried using clamps before felling and gang-nails after felling to prevent the end-splitting of poles of Eucalyptus grandis. The indications are that gang-nailed poles can be dried to acceptable levels of moisture content without excessive degrade while poles without gang-nails cannot be so dried. Clamps before felling do not appears to be necessary.

Vivekanandan, K. 1971. A new technique to assist the germination capacity of seeds in Eucalyptus. Sri Lanka Forester 10: 1-4, 14-18.

The method which is now in use for the Eucalyptus is the Germination Disk Method which is less elaborate petri disk germinator Dish Method suitable for testing a large number of seed samples is described. The Germinator used in the new method is constructed out of petri dish, glass slide and absorbent paper.

Vivekanandan, K. 1975. The present status of tree improvement work in Sri Lanka. Sri Lanka Forester 12: 1-4, 95-100.

Genetic improvements of Eucalyptus and species trials of E. alba, E. tereticornis, E. bicostata, E. bosistoana, E. viminalis, E. nitens, E. cypellicacarpa, E. microtheca, E. maculata and E. tetradonta have been discussed. Provenance trial have been done in 4 known provenances of E. camaldulensis. Plus tree selection and progeny tests have been done with using a total of 60 plus of E. grandis and 30 plus of E. microcorys.

Vivekanandan, K. 1978. Variation in wood density in E. camaldulensis. Sri Lanka Forester 13: 1-4, 71-72.

The variation in density in five trees of Eucalyptus camaldulensis from a 10 year old plantation in Wakaneri was studied. The density (basic and air-dry) decreased with height, and the mean basic density varied from 0.61 g/cc and the density at 15% moisture content varies from 0.77 g/cc to 0.85 g/cc.

Vivekanandan, K. 1979. Performance of provenances of Eucalyptus in the Dry zone in Sri Lanka. Sri Lanka Forester 14: 1-4, 49-54.

Five provenances of Eucalyptus tereticornis, two provenances of Eucalyptus alba and two provenances of Eucalyptus camaldulensis were compared in a field trial in the dry zone. The trial was planted in November 1957 and their relative performance was assessed in March, 1979. Provenances of E. tereticornis was superior in both form and growth and of these, three provenances from and Queensland (Helenvale, Mt. Garnet and N.W. Laura) show great promise as future seed sources for dry zone reforestation.

Worthington et al. 1953. Notes on Eucalyptus in Sri Lanka. Sri Lanka Forester 1: 1-4, 112-122.

The introduction in Eucalyptus in Sri Lanka, description on plantation trials have been discussed. The attempt made by the Botanic Gardens staff who obtained seeds of 50 spp. of Eucalyptus from Australia in 1882 and planted at Hakgala Botanical Gardens, laying down of 7 series of arboretum plots to test the performance of Eucalyptus under forest conditions were discussed in length.


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