Experience with Eucalypt Plantations: Their Environmental Social, Economic Aspects and Policy Issues in the Butwal Plywood Factory (BPF) Forestry Program - Nepal - Pran Jeevan Nidhi

BPF United Mission Forestry Programme, Nepal

ABSTRACT

Diversion of forest land to agriculture poses a long term wood supply problem to forest industries. The BPF-UMN Forestry Program was initiated to produce future raw material for the factory, in tree farming. The program has conducted research on the establishment of Eucalyptus camaldulensis and on the combination of E. camaldulensis with legume tree species. Objectives are to evaluate different cultivation techniques and intercropping on the growth of E. camaldulensis. Results indicate no significant impact of plants as palmarosa grass, Sesbania spp., lentils, Cassia siamea and Indigofera spp. on the establishment and growth of E. camaldulensis. Utilizing alley spaces within E. camaldulensis plantations is an attractive system for producing cash crops. Evaluation of E. camaldulensis growth with six legume species, Dalbergia sissoo, Cassia siamea, Leucaena leucocephala, Acacia catechu and Acrocarpus fraxinifolius indicate growth and yield of all species in combinations have not shown deleterious effects. Socially, local community resident’s interest in planting E. camaldulensis on their private land has been increasing since the program began selling seedlings in 1986. There has been no complaints from community residents regarding negative environmental impacts.

Key words: Eucalyptus camaldulensis, Nepal, intercrops, tree farming, agroforestry.

DESCRIPTION OF THE BPF FORESTRY PROGRAM

Introduction

Large tracts of forest in the Terai region of Nepal are being converted into agricultural land due to accelerating population growth and the accompanying need of residents to feed themselves. Land availability and the reduction of important sources of timber is now a main constraint to reforestation efforts. A further serious threat of the reduced forest resources is a negative impact on wood based industries. As a result, industries depending on timber as raw material must either close down or process substandard timber as a substitute.

In an attempt to address this situation, an agroforestry program was started in 1985 by the United Mission to Nepal’s (UMN) Butwal Plywood Factory’s (BPF) forestry program. The original intention of the program was to lease degraded forest land from His Majesty’s Government of Nepal (HMG/N) which would be cleared and replanted with fast growing timber species. A total of 160 ha of land was leased through a letter of understanding with the Forestry Department for this purpose. Sixty five (65) ha were planted with a variety of timber, fuelwood and fodder species including eucalypt species, to determine the best candidates for, not only timber production for BPF, but also for species which would be suitable for local community utilization. The remaining 95 ha are being managed for natural sal (Shorea robusta) regeneration.

In addition to BPF’s leasehold forestry program, a second strategy to produce timber resources was developed in 1986 - a Farm Forestry Program. Due to the scarcity of potential leasable land from HMG/N, the program sells various tree seedlings and an extension service to farmers of the three districts surrounding its central office in Butwal; that is, Rupandehi, Nawalparasi and Kapilbastu districts. A total of 11,370 Eucalyptus camaldulensis seedlings has been provided to 225 farmers up to the end of 1992.

The program’s major experience with Eucalyptus species has come from trials established on the leased land. There eucalypt trees have been intercropped with a variety of nitrogen fixing tree species as well as a variety of crops, herbs and cash crops which are grown to provide income as well as research opportunities on agroforestry intercropping practices.

BPF Forestry Program Objectives

In an attempt to fulfill a short term supply of raw material, the forestry program was initiated with the following objectives:

• To demonstrate the economic feasibility of commercial agroforestry plantations in the Terai;

• To develop and demonstrate industrial plantations with high yield timber, fodder and food species using an agroforestry system;

• To supply BPF and local wood-based industries with raw materials (timber); and

• To benefit local communities by supporting them in tree plantations and environment protection.

Site Description

1. Location: Town of Butwal, Rupandehi District, Western Region, Nepal.

2. Elevation: 152 meters.

3. Climate: Rainfall in Rupandehi District averages 2,288 mm per year; almost 1,900 mm of this falls during the monsoon months of June-September. The 6 month dry period, November-April, receives only about 300 mm of rain; average maximum temperature ranges from 22^oC in January to 30^oC in May; average monthly minimum temperatures vary from 11^oC in January to 26^oC in July. There is no occurrence of frost during the cool season.

4. Soil type: Soils are sandy loam and generally homogenous throughout the area.

5. Topography: Gently undulating.

HISTORICAL BACKGROUND OF EUCALYPTUS

Eucalypt was introduced in Nepal some 50 to 60 years ago and planted as avenue trees along road sides in the Kathmandu valley at the altitude of 1,350 m. Elsewhere a few small stands of eucalypts can be seen in the hills that have mainly been established for trial and demonstration purposes. Although growth has been reasonable, Eucalyptus species do not seem well suited to the elevation and climate conditions of the hills of Nepal.

Although the growth the Eucalyptus in hills has been disappointing, the situation is very different in the Terai (the area where the plains of India extend into Nepal) where elevations are generally below 300 m. At Sagarnath (150 m.) in eastern Nepal on the Terai, there are some quite promising eucalypt plantations. During 1981-85, Mr. K.J. White established several Eucalyptus species trials as well as plantations at Sagarnath for the primary purpose of fuelwood production. Experience indicates that E. camaldulensis is suited for this area for it’s general adaptability to sites and conditions found in the Terai as well as it’s high yield and utility for a variety of products currently in demand in the area.

EUCALYPT RESEARCH PROGRAM

There are two research activities related to Eucalyptus underway since the program was established. They are the Eucalyptus establishment trial and the Eucalyptus in combination with legume tree species trials.

Eucalyptus establishment trial

The trial was established in summer 1989 with the objective of evaluating the effect of cultivation and intercropping on the growth of eucalypt trees and the interaction between eucalypt and Acrocarpus fraxinifolius. However, for the purpose of this paper, information regarding the latter species is not considered. The experimental design is made by splitting a plot with 3 replications of 8 treatments. The total plot size is 8 x 14 trees with spacing 4m x 2m. The assessment plot size is 9 trees/species and treatment. The Lay out of trees is shown in Figure 1. Treatments included: 1) spot weeding; 2) spot weeding plus harrowing; 3) spot weeding plus harrowing plus summer crop, Sesbania aculata; 4) spot weeding plus harrowing plus summer crop, Sesbania aculata plus winter crop; 5) spot weeding plus harrowing plus aromatic grass; 6) spot weeding plus harrowing plus interplanting Sesbania grandiflora; 7) spot weeding plus harrowing plus interplanting Cassia siamea; 8) spot weeding plus harrowing plus interplanting Indigofera teysmanni. (Detail in Appendix 1).

Figure 1. Layout of eucalypt establishment trial.

+ = Eucalyptus camaldulensis

* = Acrocarpus fraxinifolius

Results and discussion, Eucalyptus establishment trial

Data of growth responses to treatments for individual replications is given in Figures 2, 3, and 4. The following Figure 5 provides the statistical analysis for the three replications.

Figure 2. Replication 1

* Due to technical and management problems data for these treatments were not considered valid.

T1 Spot weeding, Control

T2 Spot weeding + harrowing

T3 Spot weeding + harrowing + summer crop (Sesbania aculata)

T4 Spot weeding + harrowing + summer crop (Sesbania aculata) + winter crop

T5 Spot weeding + harrowing + aromatic grass (Palmarosa)

T6 Spot weeding + harrowing + interplanting (Sesbania grandiflora)

T7 Spot weeding + harrowing + inter-planted (Cassia siamea)

T8 Spot weeding + harrowing + inter-sowing (Indigofera teysmanni)

Figure 3. Replication 2

* Due to technical and management problems data for these treatments were not considered valid.

Figure 4. Growth and survival measurements. Replication 3

* Due to technical and management problems data for these treatments were not considered valid.

Figure 5. Eucalypt establishment trial

Note: Detail of replications in Figures 2-4

CV% = Coefficient of variation; LSD = Least significant difference; * = Significant at.05 level;

** = Significant at.01 level; NS = Non-significant

Discussion

Treatments show significant difference in years 1990 & 1991 with respect to plant height. Treatment T4 (spot weeding + harrowing + summer crop + winter crop combination) is the best regarding maximum plant height in comparison to the other treatments, except treatment T5, which does not significantly differ with treatment T4.

All treatments except T4 are not significantly different in comparison with the control T1 (spotweeding). Therefore, intercropping summer and winter crops with eucalyptus is advised and recommended to get maximum profit because it does not appear to adversely effect eucalyptus plant growth in height. In 1991, only treatment T4 was superior and significantly different to the control and the other treatments.

Up to 1992, there appears to be no adverse effects on eucalyptus growth in respect to diameter from intercropping. Therefore, intercropping is advised and recommended to receive maximum utilization of the same land.

Conclusion

From the results recorded up until 1992, the conclusion can be drawn that intercropping should be done in eucalyptus plantations to maximise production (profit), because there is no adverse effect of intercropping on eucalyptus growth. In fact, the combination of intercropping appears to enhance the eucalyptus growth in height and diameter. Growing of crops both in the summer and winter seasons is advised. Harrowing was done through out all treatments and was important for breaking up the soil, allowing for better infiltration of water as well as preparing the soil for planting the intercropping species. Therefore, to maximize the benefit of an eucalyptus plantation, especially in the short term, intercropping with profitable and demanded species as done in these trials would be recommended.

Eucalyptus in combination with legume tree species trial

The trial was established in 1986 with the objective of determining the growth performance of eucalypts interplanted with nitrogen fixing legume trees. The experimental design was an observation plot with six treatments and individual plot size was 42 trees (6 x 7 trees). Spacing was 1.5m x 3m and the assessment plot size was 3 x 4 trees. Treatments covered: T1 Control: Eucalyptus camaldulensis + Eucalyptus camaldulensis; T2 Eucalyptus camaldulensis + Acacia catechu; T3 Eucalyptus camaldulensis + Acrocarpus fraxinifolius; T4 Eucalyptus camaldulensis + Leucaena leucocephala (K-8); T5 Eucalyptus camaldulensis + Cassia siamea; T6 Eucalyptus camaldulensis + Dalbergia sissoo. The layout and admixture of species are shown in Appendix 2. An assessment at age 6 years follows.

Figure 6. Average measurement of E. camaldulensis in tree mix trials

Observations

As an early crop (T2), eucalypt could be harvested as fuelwood or poles, while catechu could be managed for katha/cutch production as a final crop. Acrocarpus and eucalypt (T3) could be harvested in an interplanted arrangement for fuelwood (eucalypt) and timber (Acrocarpus). A mixed plantation of eucalypt and Leucaena (T4) could be managed for fodder and fuelwood production (Leucaena) and for fuelwood, poles or small timber from the eucalypt. Cassia and eucalyptus interplantings (T5) appear potentially useful for managing as fuelwood plantations. The low and spreading crown of Cassia reduces the need for weeding. Cassia could be managed on a coppice cycle for fuelwood while the eucalypt could be harvested when they attain suitable sizes for either fuelwood, poles or small timber. Mixed plantations of eucalypt and sissoo (T6) could be managed for fuelwood or small poles (eucalypt) as an early crop and for high quality timber (sissoo) as a final crop.

Conclusions

1. Under treatment T1, the growth of E. camaldulensis without any nitrogen fixing trees was better than treatments T3, T4, T5 & T6. Under other treatments growth of E. camaldulensis was acceptable.

2. Under treatment T2, the growth of the Eucalyptus was seen to be better than the other treatments; Acacia catechu appears to be a favourable trees to grow in combination with E. camaldulensis.

3. On the basis of the above research, growth of E. camaldulensis trees are doing better without legume trees. This indicates that nitrogen produced by the legume trees in the soil does not seem to affect soil fertility which benefits the eucalypt trees.

ECOLOGICAL ASPECTS

Soil

Under soil aeration aspects, the program took into consideration the following criticisms that have been suggested concerning eucalypt plantations i.e. eucalypts lead to an increase in water run off and soil loss, do not enrich the soil and make the soil acid. Ocular observations in BPF's trials seem to indicate that soil conditions under eucalypt trials did not vary significantly with those found in other species trial areas. Soil samples taken in 1989 and again in 1992 resulted in the following data.

Figure 7. Soil fertility levels under eucalypts after three years

Local community people usually plant eucalyptus trees procured from BPF’s Forestry Program on poor soils. The trees are able to utilize the scare moisture in such areas. The tree is also planted on field bunds along roads, canals and acts as wind breaks or shelter belts. The planting provides an efficient source of materials while being able to tolerate poor and degraded soil.

Water

Although the program has not measured nor kept records on the depth of the local water table, the physical appearance of the soil and depth of water table seems not to have been effected to date. Winter crops have been growing well, which indicates that the water table has not been lowered.

Wildlife

Deer and other wild life have caused some damage from time to time by rubbing the bark of the trees.

ECONOMIC AND SOCIAL ASPECTS

Economic

From the economic point of view, eucalypt has increased local incomes as farmers are selling tree branches. There is a possibility of distilling the leaf, from which oil can be sold to the herb processing Department in Kathmandu. It also increases additional employment for downstream industries. Community members can use these trees for fuelwood as well as for use in constructing local thatch houses.

Social

Eucalypt seedlings are being planted by community residents in various parts of the District to meet the ever increasing demand for fuelwood and timber on account of their capability for rapid growth and high yield within a short period and their ability to survive under the Terai edaphic and climatic conditions. Farmers decide themselves on spacing because of their local conditions related to soil type, moisture regime and available inputs.

Farmers are interested in planting eucalypt due to the handsome profit being obtained from their sale. The program’s distribution of Eucalyptus camaldulensis seedlings are as follows.

Figure 8. Eucalyptus camaldulensis seedlings distributed by BPF

GUIDELINES & RECOMMENDATIONS

On the basis of BPF Forestry program’s experience and research, the following suggestions for farmers and nursery men have been developed.

1. Most of the farmers have low lying land and if they plant eucalypt seedlings just after the onset of the monsoon the seedlings may die due to flood and water logging. Therefore, seedlings should be planted after the monsoon.

2. For better growth and survival seedlings should be planted after ploughing for. Weeding should be done twice in a year before and after the monsoon up to two year. Eucalypt seeds should be collected from mature trees and should be fresh, not more than one year old. Producing seedlings in plastic covered sheds is better than seedling production in greenhouses for the Terai area of Nepal.

3. One person in each country should be nominated for long term commitment to research work on E. camaldulensis so that the environmental, social and economic impacts and effects of such an exotic species may be monitored and disseminated.

4. Intercropping agricultural crops with eucalypt plantations has positive influence on the growth of the trees, as well as providing for short term returns.

5. Mono-cropping of eucalypts in plantations does not seem ecologically nor economically feasible.

APPENDIX 1

TREATMENTS

T1 Spotweeding (Control): Clean weeding is done around the trunk of all trees in all trials to a radius of approximately. 5 meters two times a year; before the monsoon season (May) and after the monsoon season (October).

T2 Spotweeding + harrowing: This treatment is done twice a year at the same time of spotweeding. Harrowing is done throughout trial area. The purpose of harrowing is to determine the potential difference in water percolation and moisture loss compared to the other treatments.

T3 Spotweeding + harrowing + summer crop (Sesbania aculata): Harrowing and spotweeding is done as above. Sesbania seed is broadcast sown immediately following the first harrowing and the plants harvested just before the second harrowing. The objective of this treatment is to determine whether the nitrogen fixing properties of Sesbania benefit eucalyptus growth as well as being a cover crop, and if soil moisture retention also is a benefit.

T4 Spotweeding + harrowing + summer crop (Sesbania) + winter crop: Spotweeding, harrowing, planting and harvesting of Sesbania is done as above. A winter crop of either lentils or sesame will be planted after the second harrowing and harvested three to four months later (February).

T5 Spot weeding + harrowing + aromatic grass: Spotweeding is done as above while harrowing is done once prior to planting the grass. Aromatic grass (palmarosa) slips are planted throughout the trial plot at trial establishment and remain for four years. The harvesting of palmarosa is done three times during each year and distilled at the same time. This treatment evaluates the effect of a long term herb coverage.

T6 Spotweeding + harrowing + inter planting Sesbania grandiflora: This treatment is the same as treatment number 3 with the difference being a change in intercropping specie.

T7 Spotweeding + harrowing + inter planting Cassia siamea: Spotweeding and harrowing is done as in treatment 2. Cassia seedlings are inter planted with the eucalypts seedlings with a spacing of. The purpose of this treatment is to observe the effect of nitrogen fixing tree species on the growth of eucalypt trees.

T8 Spotweeding + harrowing + inter planting of Indigofera teysmanni: This treatment is done the same as treatment 7 and with the same purpose.

APPENDIX 2

EUCALYPTUS AND LEGUME TREE COMBINATION TRIAL

Layout:

+ = Eucalypt * = Legume trees

Treatments:

T1: Control: Eucalyptus camaldulensis + Eucalyptus camaldulensis

T2: Eucalyptus camaldulensis + Acacia catechu

T3: Eucalyptus camaldulensis + Acrocarpus fraxinifolius

T4: Eucalyptus camaldulensis + Leucaena leucocephala (K-8)

T5: Eucalyptus camaldulensis + Cassia siamea

T6: Eucalyptus camaldulensis + Dalbergia sissoo