Eucalyptus Plantations in Nepal - S.N. Khanal

Forest Products Development Board, Ministry of Forests Kathmandu, Nepal

ABSTRACT

In Nepal 80% of domestic and industrial energy consumed is provided from fuelwood, largely from natural forest, which is being depleted at an increasing and unsustainable rate. No visible or viable change in this pattern is seen in the future. An integrated model demonstration plantation largely based on eucalypt species in the Bhabar Terai showed that E. camaldulensis and E. tereticornis were the most suitable species in terms of adaptability and productivity. The project provided rural employment and substantial intercrop opportunities; intercrops stimulated tree growth and reduced costs in fire protection. The plantations are rain fed and do not interfere with the deep water tables. Impact on wildlife is seen as both good and bad; some fauna find the plantation habitat more conducive than natural forest.

Key words: Eucalyptus, Nepal, fuelwood plantations, agroforestry, wildlife habitat.

INTRODUCTION

Nepal is a south Asian developing country, 22^o27'E, 80^o04'N, 70-8,848 m altitude; the area of 14.7 million ha is divided into five physiographic zones based on topographical, altitudinal and climatic conditions:

Terai: southern low lying, 70-300 m above sea level with a subtropical climate, tropical vegetation, of 2.1 million ha - some 14% of country land area. It contains some 8% of the natural forests of Nepal, mostly hardwood species of which 53% is sal (Shorea robusta), 40% mixed tropical forest and 7% of khair (Acacia catechu) and sissoo (Dalbergia sissoo).

Siwaliks: this area is the outer ridge of the Himalayan mountain system that crosses the length of Nepal. The elevation is from 120-2,000 m. The zone has 26% of the Nepal’s natural forest and of this forest cover, 3% is conifer, chir pine (Pinus roxburghii), 83% of hardwood with equal parts of chir pine and sal and 14% of mixed chir and hardwoods.

Middle mountain: the central belt of Nepal bounded by the Siwaliks in the south and by the High Mountain in the north. It covers 4.4 million ha, 30% of the total land area; altitude varies from 200-3,000 m. The zone contains almost one third of the natural forest of Nepal; 19% conifer, 557% hardwood and 24% of mixed forest. Most of the dense forest is chir pine with quantities of hemlock, blue pine (Pinus wallachiana) and fir.

High mountain: this zone contains heavily utilised middle mountain and sparsely populated high Himal; the upper boundary is the forest line at about 4,000 m and the lower, a somewhat diffuse line that separates extensive agriculture from scattered and isolated vegetation; on ridges this lower boundary is at 2-3,000 m but in valley bottoms can be as low as 200 m. The area is 2.9 million ha - 20% of Nepal. The zone has 30% of Nepal’s natural forest; it includes 30% coniferous (main species, blue pine, fir, hemlock), 34% hardwood and 34% mixed forest.

High Himal: the zone occupies 23% of the Nepal land area and lies above the tree line at 4,000 m. It is an area of rocky ice mountains, valleys and sweeping meadow lands; it contains 3% of the natural forest area, 30% shrubs, 40% conifers and 15% hardwood and mixed forest.

Forest flora

Forest covers 5.5 million ha, 37% of the total land area; the distribution of vegetation follows traditional altitudinal zones. Nepal is rich in flora varying from the tropical to the alpine.

Tropical: Below 100 m, there are tropical forests, predominately of sal, but along rivers khair (Acacia catechu) and sissoo (Dalbergia sissoo) replace sal. Other riverain species occur: mostly evergreen as Michelia champaca, or deciduous as Bombax malabaricum. On the foot-hills in the Western Region, sal is replaced by Terminalia and Anogeissus forest.

Sub-tropical forest: occurs at 1,000-2,000 m in the west, and 1,000-1,700 m in the east. Chir pine is found in the west, Schima and Castanopsis in the centre and east; utis (Alnus nepalensis) is also found in wet areas along streams and rivers; toon (Cedrela) and Albizia spp. are also found in this locality.

Lower temperate forest: is located at the 2,000-2,700 m the west, and 1,700-2,400 m in the east. Blue pine and several species of Quercus thrive in the zone.

Upper temperate forest: occurs from 2,800 to 3,100 m. Quercus semicarpifolia forest is found in the east and centre together with Rhododendron arboreum, Acer spp., etc. Rhododendron also occurs in mixed broad-leaved forest and becomes dominant in the very moist areas, particularly in the far east. Blue pine is distributed almost throughout, extending into the sub-alpine zone up to 4,000 m.

Sub-alpine forest: is found between 3,000-4,200 m in the west. Abies spectabilis, Betula utilis and Rhododendron occur in very wet sites, while on drier sites Juniperus indica and Caragana species occur.

Alpine zone: has no tree species but shrubby Rhododendron and Juniperus are found up to 4,500-5,000 m.

WOOD AS A SOURCE OF ENERGY

The people of Nepal are heavily dependent on forests for the supply of fuel wood, fodder and timber. The annual estimated consumption of traditional fuel is 11.3 million m³ of which dung and farm residues supply 28% in the Terai and 18% in the hills; 14% of Terai wood fuel and 33% of that in the hills is obtained from private wood lots. The sustainable harvest of fuelwood from accessible forest and shrubs is estimated at 6.8 million m³ but it is considered only 4.3 million m³ can be utilised as excess capacity in the various localities cannot be transported to meet deficits elsewhere.

The annual removal of fuelwood from forests and shrubland is some 5.4 million m³ compared with the sustainable utilisation yields of 4.3 million m³. The scarcity of fuelwood is forcing people to use more animal dung and agricultural residues for cooking and heating. It has been estimated that some time between 1985 and 1995, the annual burning of residues and animal dung could rise to 8 million tons representing the loss in production the loss of about one million tons, which is about one quarter of the present annual cereal production. There is also a loss in livestock productivity if residues are burnt as fuel instead of being used as fodder. Under the pressure of increasing human and livestock populations, the forest area has been rapidly depleted. The area of natural forest is being reduced by 26,000 ha annually - an annual loss of 0.4%. The movement from forest to shrub land and degraded forest has been immense.

Forest production is dominated by fuelwood use. Fuelwood will be the continuing major domestic requirement for the rural communities of Nepal for many years to come. In more urbanised regions and in industries, the energy need if of fuelwood and to some extent fossil fuel and electricity. However, the increasing cost of fossil fuel and electricity in recent years has led to increased substitution by fuelwood. In the Terai, for example, wood is virtually the energy source for tobacco drying and brick making industries. Reduction in available supplies and increased cost of collection may be expected to lead to reduced per capita consumption, but wood will remain a predominant source of energy for cooking and heating.

There is an increasing shortage of fuelwood in the major consuming centres - Kathmandu valley, eastern and central Terai - which obtain part supplies from distances over 150 km. As a result of these needs, the forests are being overcut with consequent serious soil erosion and flooding, causing rivers to change course annually with destructive effect on agriculture in the Terai. The accessible forest area is also being rapidly depleted by legal orientation, encroachment, commercial logging and uncontrollable cutting by rural people.

The increasing population pressure in the Terai emphasizes the urgent need for intensive management of the commercial forest resources and for the replacement of depleted and non-productive forest by higher yielding plantations.

In the context of shrinking forest resources and the imminent shortage of fuelwood in the eastern and central parts of Nepal, a semimechanised project with fast growing, high yielding plantation species commenced in the Bhabar Terai in 1978. This Sagarnath Forestry Development Project aimed to establish some 11, 000 ha (net) of fast growing short rotation species. The replacement period was set at 10-12 years and the initial fuelwood rotation at 10 years. During the testing and application period, it was concluded that appropriate tree farming strategies and practices required: full site preparation, planting of eucalypts in the pre monsoon planting rains and that optimum maintenance to give fast growth, high yield and fire protection was best given in full area intercropping for as many years as possible.

HISTORICAL BACKGROUND OF EUCALYPTS

Eucalypts were introduced some 50-60 years ago in Kathmandu where some fine avenue trees may be seen. Several trials were made; results were prominent in the Terai but above 1,000 m results were on the whole disappointing.

In assessments of four trials by the Nepal-Australian Forestry project in the Kathmandu valley, the best diameter after seven years was 12.4 cm; this could be described as moderate growth for eucalypts at 1,350 m altitude. Elsewhere a few small stands may be seen in the hills; there are no reasonably large areas of really promising stands in the hills on account of the combination of drought and cold that prevails in these areas in winter. Campbell and Bhatterai (1983) report average survival of 46% as compared to an average 68% for all species in the Nepal hill areas.

Although eucalypt growth in the hill area has been disappointing, the situation is very different in the Terai and at lower altitudes; at Sagarnath (150) there are some quite promising Eucalyptus plantations. Species selection trials by K.J. White (1981-85) showed Eucalyptus camaldulensis best suited on account of its adaptability to a range of sites, rapid growth, high yield and the utility of its timber. Figure 1 indicates the yield at five years for the three major species planted at Sagarnath.

Figure 1. Mean annual increment (MAI) at Sagarnath at 5 years (m³/ha)

The above figures clearly nominate Eucalyptus as the prime species for rapid growth and high yielding plantations in the Bhabar Terai of Nepal. E. camaldulensis is the most suitable species for the full range of soil types; presently the provenance “Petford” is the most preferred one. A range of fast growing eucalypt species for higher altitudes is shown in Figure 2.

Figure 2. Eucalypt selections for Nepal altitudes 600-7,000 m

Source: Nepal-Australia project 1980; Josi, Wyatt-Smith, 1982.
E. camal. = E. camaldulensis; E. teret. = E tereticornis;
E. maiden. = E. globulus sub spp. maidenii.

PRESENT SITUATION OF EUCALYPT PLANTING IN NEPAL

Eucalyptus was introduced into the different parts of Nepal on a trial basis only. Apart from some small scale plantations, it did not gain popularity due to the requirement of skilled nursery techniques, intensive management and above all very thorough weeding.

The Sagarnath Project is the only Nepal large scale eucalypt plantation; the project lies wholly in the Bhabar Terai, an undulating south slope in front of the Siwalik range at an altitude of 150 m. The area is crossed by a number of north south river beds seasonally flooding, otherwise dry. The climate cycle is dominated by the monsoon (June-October) with a rainfall of some 1,500 mm providing soil excess moisture in this period as 93% of total rainfall. The average temperature ranges < 10^oC in January to 35^oC in May and with R.H. % at 1500 hours from 42 in April to 82 in August. The soil weakly developed over small gravel and boulders is freely draining and has along water deficit period November-May. The project area includes three ground water zones varying in depth from 5-80 m.

The existing natural forest types were Northern Moist Sal and Moist Mixed Deciduous. The forest had a long selective logging history and was downgraded, with low standing value, of 50 m³/ha. This volume can be outgrown in a few years by well maintained eucalypt plantation, a factor strongly favouring the concept of natural forest conversion to highly productive plantation. Major species planted in the project are: Eucalyptus camaldulensis, Dalbergia sissoo and Tectona grandis. Eucalypt covers above 60% of the area planted to date; many species were tested. E. camaldulensis emerged as the most vigorous species suited to the area on the different soil types with a Mean Annual Increment of 8-30 m³. It became apparent early that the Emu Creek provenance at Petford was of maximum interest.

Figure 3. Site class yields, eucalypt MAI, Sagarnath

Source: Sagarnath inventory, T. Pukala, 1990.

Area and growing stock

Figure 4. Eucalypt plantation area and estimated growing stock

Source: Sagarnath Project 1993

The eucalypt planted area is 5,601 ha out of 9,570 ha of the total plantation. The eucalypt Mean Annual Increment (MAI), which describes the yield better than the Current Annual Increment (CAI), for a stocking of 700 trees/ha in different site conditions, is shown in Figure 3.

About 90% of the area is fair site, 9% very good and 1% poor/very poor. The growing stock is estimated to be 239,540 m³ with a sustainable annual eucalypt harvest of about 30,000 m³. The plantation area and estimated eucalypt growing stock for eucalypts at Sagarnath are in Figure 4.

UTILISATION

The main use of eucalypts in Nepal is likely to be for high volume fuelwood production and for transmission poles. The last two years harvesting records at age 10 years show per ha a harvest of 130 (25' long) electrical transmission poles and 6 chatta (stack of fuelwood, 20 x 5 x 5') i.e. 80 m³ ha of which 25% is for poles, 75% for fuelwood. It is anticipated the chemically treated poles will last 30-40 years.

Eucalypt oil is being extracted from the leaves; the Sagarnath distillation plant has a daily production capacity of 100 litres. The leaves have been found to have 10% oil content by weight.

Untreated round poles have been used as internal construction material in wooden houses. Sawn timber from this fast growing eucalypt is not generally used, warping and splitting at time of sawing.

ECONOMIC AND SOCIAL ASPECTS OF EUCALYPTUS

The plantation area is surrounded by densely populated agricultural land. With high tenancy, due to small holdings and traditional farming practice, the average incomes levels are low and much of the average income comes - not from individual held farms - but from labour earnings either on farms or other activity. The Project has direct contact with contiguous villages. Villagers have traditional rights in the project area for fuelwood and for fodder collection, as well as grazing. The Project requires village level assistance to, prevent fire, labour supply for plantation work and for intercrop activity. The Project has created an employment opportunity for some 800 permanent labour and takes up a similar number in peak periods.

Figure 5. Beneficial effect of intercrop on eucalypt tree crop at 3 years

Source: Sagarnath Project 1993

Intercropping of agricultural crops by local people is significantly important in producing substantial annual food crops an in social uplift. This activity also allows the transfer of weeding the tree crop and of eliminating fire danger. The beneficial effect of intercrops on tree growth and of agricultural crop yield and income generation is shown in Figures 5 and 6.

Figure 6. Agricultural crop yield and income generated/ha eucalypt plantation

Source: Sagarnath Project 1993. N.R. Nepal rupee, 50 = $1

Intercrops provide up to 100% fire protection and stimulates tree growth ten fold as well as saving the cost of weeding. Some 600-900 ha of 1-3 year plantation area is cultivated each year. Summer crops include: maize, millet, upland rice and sesame; winter crops include: mustard, pulses, sun flower, tobacco and vegetables. The average holding per family is 1.5 ha and the production value is about N.R. 21,000 per family.

Plantation economics

Plantation establishment cost, from site preparation and planting and maintenance up to ten years is N.R. 15,463/ha (see Figure 7). The harvest at rotation of about 10 years shows an average yield of 80 m³/ha is 6 chatta (60 m³) and 130 transmission poles (20 m³). The net profit gained from the harvested product is N.R. 73,500/ha (Figure 8).

Figure 7. Establishment and other costs up to 10 years age, Sagarnath plantation

Figure 8. Harvesting cost and revenue per ha generated from the sale of eucalypt plantation product

ECOLOGICAL ASPECTS

There can be no doubt of a major change happening in the ecological status in the Project area. Two forest types of diverse species, site classes and habitants have been changed to a simplified monoculture tree crop of uniform sizes. This change is inevitable in the programme of supplying large and increasing demands of energy fuelwood from diminishing land resources where the natural forests cannot sustain the supply, and give way to tree plantations. Some associated site improvements are noted, e.g. in thatch grass harvest, where there is an increasing yield from plantations, providing a ready source of income to local villagers.

There is fear that intensive tree cropping will cause excessive depletion of soil fertility. Tree roots deeply explore the soil profile and trap and return leached nutrients to the surface litter. The nutrients lost in wood removal are limited; most of the leaf litter is recycled thereby losses of essential minerals can be economically replaced by fertilisers.

The plantation crops are grown under rainfall irrigation. The trees have access to soil water from the annual monsoon, not to water tables in 90% of the area as these tables are at inaccessible depths, 80 m and more. Such deep water tables cannot be affected by the roots of eucalypts or even other species. It is difficult to see that the change from a complex to a simplified forest can cause or add to desertification. Changes caused by soil erosion or by rivers cutting new beds by clear felling has been minimised by retaining 50-100 m of natural forest strips along river banks and contour strips left between disced areas.

Wildlife

The change in habitat has caused hard times to monkeys, while other fauna have benefited. The plantation has provided an excellent environment for minor populations of chittal (Axis axis = spotted deer), the pea fowl (Paro crixtatul), red jungle fowl (Gallus gallus). The numbers of leopards and wild boars have also increased in numbers. Deer could increase rapidly if hunting is stopped.

PLANTATION MANAGEMENT IN SAGARNATH

The plantation is divided into square blocks of 100 ha (1 km x 1 km); each block is further divided into 4 plots of 25 ha (500 m x 500 m) and these plots are the smallest management units. The whole Block is planted at the same time using the same species.

The natural forest is cleared one to two years prior to the planting. The area is ploughed with heavy bulldozer discs and distributed to local farmers for intercropping. Planting is of container eucalypt seedlings at spacing 4 m x 2 m (1,250 plants/ha). The most important management operations area weeding and protection in non-intercropped areas and at the age when intercropping ceases. The competition of Imperata grass and other weeds can be so intense as to cause growth cessation in eucalypts. Fire alone is a sufficient reason for total failure if not managed properly. The rotation is fixed at 10 years with 2-3 rotations of coppice regeneration and then replanted with eucalypts.

The Forest Product Development Board, the executing agency of the Sagarnath Project, has expended N.R. 74.52 million as local expenditure from its sources since 1978 to 1993. Several funding supports were also given, such as: 1) US$3.633 million in the First Phase (1978-85) under the Asian Development Bank Loan and OPEC Fund: 2) US$1.869 million in the Second Phase (1986-91) again under the Asian Development Bank Loan: and 3) N.R. 16.26 million in the Asian Development Program Loan since the financial years 1991/92 to 1992/93 under a foreign assistance.

GOVERNMENT POLICIES & PROGRAMMES ON EUCALYPT PLANTATION

His Majesty’s Government of Nepal is well aware of problems caused by the rapid decline in the forest area, not only is the area under forest decreasing, but much of the remaining forest is very much degraded and producing much less than it is capable of doing. The immediate effect of forest destruction is the shortage of fuelwood, timber and fodder. Wood provides well over 80% of the energy needs of Nepal; the accessible forests are very much degraded, and if this trend is not checked - it will not last longer than the next 20 years. As the forests have suffered from a lack of proper management, the present annual growth of 2-3 m³/ha (which is very low) does not reflect their true yield potential.

The National Forestry Development Plan stresses the protective role of forestry, as well as the socio-economic importance of forest production. Action plans have been prepared for the long term development of the Forestry Sector of Nepal. In the Action Plan, four broad categories of forest production units are considered, two of which are subdivided further:

• Unmanaged natural forest.

• Managed natural forest:

  a) With no enrichment planting.

  b) With enrichment planting on about 5% of the area.

  c) With enrichment planting on about 10% of the area.

• Forest plantations:

  a) Fast growing Terai plantations with species as sissoo and eucalypts.

  b) Medium growing Terai plantations with teak and other spp.

  c) Mixed pine and broad leaf plantations in mountain areas.

• Private tree farms.

The Sagarnath forest project is a uniquely pioneer forest management operation involving for the first time in the Bhabar Terai, one management team in large scale harvesting and the sale of natural forest products, and the artificial regeneration of the site to a fast growing and high yielding wood crop. Time, with some reluctance has seen the downgrading of long known, high valued species as sissoo and teak, ecologically unsuited to 90% of the Project site, with exotic eucalypts. This project is serving as a prototype role and providing a model for similar project designs in other areas of the Terai. Eucalyptus has emerged as clear leader in utility wood production in Bhabar Terai.

The Government of Nepal has not identified other large scale eucalypt plantations than Sagarnath. Minor plantings for aesthetic reasons are made in avenues or on private land. Last year, the Government allocated funds for 1,000 ha plantation at Sagarnath, of which some 60% was planted with eucalypts. In 1993-94 a further planting of 800 ha is to be made and 60% of this will be eucalypt. The Project plantation area will be completed after two years; at that time the total area will be about 12,500 ha of which 7,000 is estimated as eucalypt. Following Project completion in two years, the Government is considering starting similar projects, not as large as Sagarnath, but in smaller areas in different parts of the Terai. No other large scale plantation of eucalypt as Sagarnath, has been planned.