Current Status of Eucalyptus Plantations in The Northwestern Philippines - Stanley C. Malab

Professor, Mariano State University

Director, Institute of Sustainable Dryland Agriculture

Batac, Llocos Norte, Philippines

ABSTRACT

Eucalypt planting is done in northeastern Philippines after harvesting reduces natural forests to marginal stands and vast anthopogenic grasslands have resulted from shifting cultivation. Government priority is to revert these to productive sustainable forest in community reforestation schemes; 3,500 families are involved in project area and as a result, cash incomes increased for some by 500%. Eucalypt is a favoured tree because of its adaptability, seed availability, ease of establishment, survival, fire resistance, ability to grow on relatively poor soil, growth rate, coppicing ability and its economic uses. E. camaldulensis is prominent with 65% of project area planted to it. Ectomycorrizal inoculation significantly increased growth; a follow on is that inoculation replaced 60-80% of inorganic applied. Organic matter, pH, N, P, increased in the first year of plantation but decreased towards the sixth year. Eucalypt plantings are not presented as universal panacea to all forest economic and environmental ills, but do help in a healthful environment, provide additional income, and lead to a better life.

Key words: Eucalyptus camaldulensis, Philippines, plantations, social forestry, mycorrhiza, ectomychorriza.

INTRODUCTION

The Philippines is a country with a total land area of 30 million ha scattered into more than 7,000 islands. Northwestern Philippines, composed of four provinces, is among the regions with vast grasslands and unproductive forest lands. Fifty years ago, this region of the country had 810,678 ha of forest area with virgin forests covering about 500,000 ha (Hamada, 1992). However, the tight economic situation aggravated by high population growth rate and political pressures led swidden agriculturists to clear much of the forests, what's worse was the fact that the remaining forest areas was logged to supply the requirements of wood based industries. These indiscriminate activities converted many of the forest lands into marginal lands. Thus, about 335,500 ha of unproductive lands are now evident throughout the region (Hamada, 1992). The Philippine Government had given top priority to convert these marginal grasslands into sustainable forest production units.

Revegetation of these marginal lands is a formidable task. Marginal lands in this region are characterized as low in organic matter, highly eroded and poor in mineral nutrients especially nitrogen and phosphorus (Malab, 1992; PFDPIN, 1992). Under this condition, growth and survival of seedlings are very poor and require careful selection of species to be planted.

Several strategies had been adapted to develop and make these marginal lands productive. The use of introduced species proven successful in the reforestation of grasslands in other parts of the world is among these strategies. In 1984, the Philippine Government implemented the Philippine Forestry Development Project in Ilocos Norte (PFDPIN) to reforest about 25,000 ha of marginal public lands in northwest Philippines with fast growing species. In this project, Eucalyptus is among the recommended and priority species for revegetating these degraded sites because of its wide adaptability, availability of seeds, easy establishment and its multiple economic uses.

This paper presents some information and issues concerning the potential of Eucalyptus as reforestation species and source of fuelwood for the heavily depended wood based industries in Northwest Philippines.

BACKGROUND OF EUCALYPTS IN THE PHILIPPINES

Eucalyptus, of the family Myrtaceae is one of the widely distributed tree species around the world. It is one of the most promising species because of its multiple uses. Eucalyptus is an excellent pulpwood and fuelwood. The wood makes good charcoal which is suitable for steel manufacturing (NAS, 1980). Most of the species are good for poles, fence post, furniture manufacture, mine timber, confectionery clothes, cleanser, and proven to be a good reforestation species for degraded lands (FAO, 1981; PFDPIN, 1992). In urban and rural areas, Eucalyptus is commonly planted in backyards and field boundaries as shelterbelts, and along roadsides for beautification purposes (NAS, 1980). Eucalyptus oil is also recommended for medical purposes as well as in perfume making (RISE, 1990).

The most widely known species of Eucalyptus in the Philippines is E. deglupta Blume, locally known as Bagras. It is an indigenous Eucalyptus species found in Southern Philippines, specifically in the Provinces of Agusan, Cotabato, and Zamboanga. It is also found in Papua New Guinea, Indonesia, Celebes and Mollucas (RISE, 1990). The species is one of the fast growing tree species commercially grown in the country for pulp and paper.

Bagras is one of the largest and tallest tree species in the Philippines. It can attain a diameter of 45 cm and a height of 45 m in 14 years (Gianan and Tagudar, 1970). It thrives best in areas with 2,500-3,500 mm of rainfall and a temperature of 30-32°C. The tree requires deep, moderately fertile and well drained soil for favorable growth with an elevation up to 600 m above sea level. The species bears fruits throughout the year and starts flowering at a very early age, usually 3-4 years under plantation condition (RISE, 1990). In December 1968, a large scale E. deglupta plantation for pulpwood production was established by the Bislig Bay Lumber Company in Agusan, Philippines (Gianan and Tagudar, 1970).

As early as 1970, some species of Eucalyptus was already introduced in the Philippines. Encouraged by the potential of the species, species and provenance trials, on two species of Eucalyptus, E. camaldulensis and E. tereticornis, were conducted in 1985 at Maringalo, Nueva Ecija, Northern Philippines under the Australian-ASEAN Non-Conventional Energy Development Program. Initial results of the trials showed promising performance (Dalmacio, 1986; Dalmacio et al., 1987). Additional species and provenances of Eucalyptus were introduced and planted in 1987 at the Carranglan Reforestation Project in Nueva, Ecija, Philippines (Dalmacio et al., 1987). The species included in the trials were three provenances of E. camaldulensis, three provenances of E. tereticornis; and one provenance each of E. urophylla; and E. brassiana. The seeds were provided by the Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia.

In a separate trial in 1987, 11 Eucalyptus species were introduced in Northwestern Philippines at the PFDPIN project areas. Species included were: three provenances of E. camaldulensis; three provenances of E. brassiana; two provenances of E.tereticornis; one provenance each of E. alba; E. citriodora; and E. urophylla. Seeds were directly obtained from Australia by PFDPIN (1988).

Eucalyptus camaldulensis. This species is the most widely planted Eucalyptus in the world. It is resistant to fire and has a broad range of adaptability from tropical to subtropical climates. It also has the ability to grow on relatively poor soils. The wood is sometimes used for paper pulp. When fully dry, it is an outstanding fuel. Highly valued in Australia, it is also useful for general construction. In the Philippines, this species was found as a good wood substrate for the culture of 'shiitake' mushroom, the most important mushroom in Japan (Zamora, 1986). Annual wood yield ranges from 17 to 30m³/ha in good sites. It can be regenerated by coppicing even up to six or more rotations (NAS, 1980). This species is very dominant around the Mediterranean (Spain has 114,000 ha while Morocco has 87,000 ha). Plantations are also found in Pakistan, Uruguay, Argentina and Kenya (NAS, 1983), and recently in the Philippines, (PFDPIN, 1992).

Eucalyptus tereticornis. This is another fast growing species that has the widest latitudinal range. It has been introduced in many tropical and subtropical countries. Its wood is hard, heavy and strong. It is immune to termites and dry rot, making it as one of the most durable Eucalyptus woods for timber, poles, and post. The establishment of many plantations has been encouraged because the wood is also very excellent for fuel and charcoal. Its leaves are among the commercial sources of eucalypt oil, while its flowers are an important source of nectar for honey production. In good sites, yield could reach to 20 to 25 m³/ha/yr for the first 10 years (NAS, 1983).

Eucalyptus urophylla. This is one of the species recommended by the Panel of the Advisory Committee on Technology Innovation as a fuelwood species for humid regions, especially in areas where rainfall is more than 1,000 mm per year. It grows best on deep, well drained, medium to heavy non calcareous soils at altitudes of 300 m to 3,000 m. The wood is less dense than those of other species, but is also used as building poles and fence posts. It gives a high pulp yield of 20 to 30 m³/ha/yr under favorable conditions (NAS, 1983).

Eucalyptus brassiana. This species is also recommended by the Panel of Advisory Committee on Technology Innovation as one of the fuelwood species in the humid tropics. It is a fast growing species and adapted to a wide variety of site conditions at low elevations up to 650 m. The wood is moderately dense with a hard, heavy, strong and durable heart wood. Aside from use as firewood, it is also used for general construction purposes. This species tolerates periodic flooding and a dry season of up to five months (NAS, 1983).

Eucalyptus citriodora. This species is an attractive tree with a white, red or faintly bluish bark. It grows to about 45 m tall, typically increasing by 3 m per year in the first several years. Its trunk is straight and white, about 1.3 m in diameter, and an open, graceful crown of narrow, pendulous foliage cover the canopy. It is adapted to cultivation in a number of countries with widely differing climates and soil types. This species withstands both high (29-35°C mean monthly maximum) and light frosts. The wood is very hard, strong, and tough with a relatively low shrinkage (in terms of density) in drying. It makes a first class saw timber and is used for general construction, poles, and tool handles. Its leaves yield a lemon scented oil rich in citronella which is used in the perfume industry (NAS, 1983).

SPECIES AND PROVENANCE TRIALS

In 1984, PFDPIN undertook a massive tree planting program. A large number of species was recommended for planting based on findings around the world. These findings may be a good basis for selecting species but there was the danger of extrapolating results from totally different agro-climatic condition. Also, there was always the need for eliminating and providing trials for a reasonable number of species for major and specific sites. Thus, a trial planting of 16 exotic and indigenous tree species was undertaken in the hill land environment of the project site. The tropical dry forest, a transition from semi arid to sub humid (Holdridge et al., 1972) condition with long dry months (October to June) and annual rainfall of 1,800 mm, and the low organic matter (1.5%) and available phosphorus, 10 mg/g (PFDPIN, 1990), make it the ideal site for testing the ability of the species to survive under adverse conditions.

After four years of evaluation, five of the original 16 introduced species were chosen for the immediate rehabilitation of the denuded site. These were Acacia auriculiformis, A. mangium, Eucalyptus camaldulensis, Casuarina equisitifolia, and Gmelina arborea. Although E. deglupta showed a favorable performance in terms of height growth during the first three years, it was eventually dropped because of lack of seed supply and very low survival (50.6%). Height and diameter of the selected species were significantly higher than the rest of the species tried. Their survival, however, was not significantly different (Malab et al., 1992; PFDPIN, 1992).

The performance of E. camaldulensis in the initial trial encouraged the introduction in 1987 of additional species and provenances in the same site. As mentioned earlier in this paper, 11 Eucalyptus species and provenances were included in the study: three provenances of E. camaldulensis; three provenances of E. brassiana; two provenances of E. tereticornis and one provenance each of E. alba, E. citriodora and E. urophylla. The average height of the Eucalyptus species five years after planting ranged from 2.11 to 4.20 m for E. alba (Code 14533) and E. camaldulensis (Code 14338), respectively. The average diameter 10 cm above the ground showed different pictures with E. brassiana (Code 13412) exhibiting the biggest diameter (3.5 cm), while E. alba showed the least (2.1 cm). E. camaldulensis (Code 14338) had the highest survival rate while E. citriodora had the lowest (Figure 1).

In another part of the Philippines, Dalmacio et al., (1987) established a separate provenance trial of Eucalyptus in Maringalo, Carranglan, Nueva Ecija inside the Talavera watershed. The average annual rainfall is 1,803 mm. The research site, located at an elevation of 240 m above sea level, is typical of marginal hilly land, very acidic (pH 4.3) and low in organic matter (2.36%). The dominant vegetative covers are Themeda triandra and Imperata cylindrica which is subjected to burning almost every year.

Figure 1. Provenance, height, diameter and percentage survival of Eucalyptus species five years after planting at Pasuquin, Ilocos Norte, Philippines

* = CSIRO seedlot number. Source: PFDPIN (1992)

The height, diameter at 5 cm above ground, and survival of the various Eucalyptus species and provenances in Nueva Ecija, Philippines are shown in Figure 2. Average height of the trees six months after planting ranged from 64.89 cm for E. urophylla (Code 14534) to 93.78 cm for E. camaldulensis (Code 14847). As in height, the diameter of E. camaldulensis was also significantly bigger than the other species. Survival was quite high, 91-95% for all species except E. urophylla and E. tereticornis which is 65% (Dalmacio et al., 1987).

Figure 2. Provenance, height, diameter at 5 cm above the ground and percentage survival of Eucalyptus species six months after planting, at Maringalo, Caranglan, Nueva Ecija, Philippines

* Means denoted by the same letters are not significantly different at p = 0.05 based on Turkey's w procedure.

Source: Dalmacio et al (1987)

In both Eucalyptus provenance and species trials, E. camaldulensis generally confirmed a better performance than the other species thus far. Its performance, however, is still below its potential compared to its growth in its origin.

EUCALYPTUS PLANTATION ESTABLISHMENT AND DEVELOPMENT

The community based reforestation scheme

The implementation of PFDPIN is one of the initial steps towards the realization of an intensive reforestation program of the Government in Northwest Philippines. The project was financed by the Asian Development Bank through a loan which was approved in 1983. Its major objectives are to reforest about 25,000 ha of open public forest land with fast growing tree species for the production of fuelwood, pulpwood and timber. Social forestry programs in the form of developing improved pasture and agroforestry farmlots for fuelwood, timber and other crops on about 1,000 ha of public land were incorporated. About 65% of the total area scheduled for planting from 1987 to 1992 was planted to E. camaldulensis.

The majority of the Eucalyptus plantations were established through the Community Based Reforestation Scheme (CBRS). Recognizing that non-governmental organizations (NGO's) are effective partners in forest development, contract to reforest some tracts were awarded to qualified organizations. Priority areas were given to those within the vicinity of the project site.

Normally, 100 ha or more were awarded to an NGO to reforest. An NGO could also be a community in the project site. The contract covers land clearing, preparation, planting, weeding, protection, and maintenance for three years after planting. Before any contract was awarded, the contractor was given a training on the various aspects of plantation establishment and management to ensure the proper execution of silvicultural prescriptions and other cultural management procedures. For all activities, a simple management plan highlighting the major steps to undertake in the implementation of the contract was drawn up. Periodic assessment, usually after the completion of every major activity, was undertaken to determine payments to be made and evaluate the performance of the tree crops. Contractors who were able to meet satisfactorily the set standards were given incentives during the turnover of the plantation (three years after planting) and then another contract was awarded.

Several reasons for the success of the CBRS in establishing Eucalyptus plantations were due to high field survival (75%) and good growth of the species, ease of establishment, and its adaptability. Beyond a survival rate of 65%, contractors were paid additional cash incentive. Thus, they obtained more income. This contractual reforestation program provided employment to about 5,300 families in the project site and as a result, their income was increased by as much as 500% (FDPIN, 1992; Arias, 1993). Encouraged by the success of CBRS, the Department of Environment and Natural Resources of the Philippines has adapted this scheme for its nation-wide reforestation program.

On the other hand, despite the claims that Eucalyptus is not good for erosion control (Poore and Fries, 1985), it is still widely planted by farmers in the social forestry projects of PFDPIN and other areas of Northwest Philippines, partly because of the availability of the planting material, its adaptability and fast growth, ease of establishment and potential for repeated coppicing for quick source of fuelwood.

In other parts of the Philippines, extensive Eucalyptus plantations have been also established by the Government and private institutions for different purposes. The Paper Industries Corporations (PICOP) in Southern Philippines had developed a large scale plantation of E. deglupta in support to the raw material requirements for their pulp and paper manufacture. The National Irrigation Administration also established plantations of E. camaldulensis for water-shed rehabilitation in Pantabangan, Nueva Ecija, Philippines. The ASEAN-New Zealand Afforestation Project in Mayantoc, Tarlac, Philippines, also uses E. camaldulensis for afforestation purposes.

Management and growth of E. camaldulensis

The performance of E. camaldulensis under the CBR Scheme of planting has been very encouraging. Growth of trees planted under this scheme was far much more impressive than those provenance trials earlier presented in this paper (Diagram 4a and 4b). After eight years, the dominant trees (compose 60% of trees/ha) reach a height of 13.5 m, with a diameter of 13.0 cm and a survival of about 75% (PFDPIN, 1992). Based on the estimates made earlier in the project the trees are expected to yield 54 m³/ha but it appears that this yield may not be met especially in the poor sites.

The good performance of the species was partly due to the strict implementation of cultural management practices and protection. PFDPIN adopted intensive planting and maintenance practices to ensure faster growth of seedlings in the field. Holes measuring 30 cm x 30 cm and spaced at 3 m x 3 m, were prepared on the onset of the rainy season. Ring weeding and cultivation around the plant were conducted twice a year during the first three years. The plants were fertilized with 55 g urea (45-0-0) and 15 g rock phosphate after the first weeding.

Effect on soil: Improvement or degradation?

Among the beneficial effects of trees, maintenance of soil organic matter through the supply of litter and root residues is the major cause of soil fertility improvement and the prime mover for the other soil improving processes (Young, 1989). However, Lundgren (1978) in his review on the effect of fast growing tree plantation on soil dynamics in tropical highlands and subtropical regions concluded that the establishment of the most commonly used species, such as Eucalyptus, is associated with a relatively pronounced deterioration in soil physical, chemical and biological properties.

A six year old Eucalyptus camaldulensis plantation at PFDPIN seems to confirm the conclusion of Lundgren (1978). Organic matter levels, pH value, nitrogen and phosphorus increased during the first year of the plantation but decreased towards the six year period as shown in Figure 3. According to Young (1989), annual litter fall is generally low during the early stages of crop establishment. This could explain the decreasing trend of soil fertility towards the six year period. He indicated, however, that an increasing trend in the soil organic matter level may be realized at later periods since litter fall is higher in older plantations, and two thirds of the gross annual nutrient uptake is returned to the soil through the litter (Young, 1992; Turner and Lambert, 1983). It could also be possible that soil under E. camaldulensis may continue to deteriorate if the trees are harvested at an early stage. Based on the data of George (1982) and Turner and Lambert (1983), a whole tree harvest of 10 year old Eucalyptus with a biomass of 90,000 kg/DM/ha removes the following nutrients (kg/ha) from the system: nitrogen 100-400, phosphorus 10-100, potassium 100-250, and calcium 1,000.

Figure 3. Chemical properties of soils under E. camaldulensis at the PFDPIN project site, Pasuquin, Ilocos Norte, Philippines

Source: PFDPIN (1992)

Coppicing ability of E. camaldulensis

Among the characteristics of species that are often considered in the selection of species for reforesting areas with long dry season are resistance to drought and fire. Experiments with eucalyptus in the Philippines revealed that E. camaldulensis is fire resistant. Observations made at the PFDPIN indicated that the trees of three year old E. camaldulensis in a 3,000 ha plantation burned at the height of the summer months in 1993 survived and regenerated fast after fire. A 100% survival was recorded and about five to 10 coppice or new shoots developed from each plant one month after the fire. The coppices were about 260 cm in height and 24 mm in diameter five months after the plantation was burned (PFDPIN, 1992).

Earlier, Agpaoa (1980) reported that 48% to 53% survival was recorded five to six months after a plantation was burned within the Binga-Ambuklao watershed in Benguet, Philippines. He also reported a 48% survival of the species eight months after a plantation was burned in a degraded site at Conversion, Pantabangan, Nueva Ecija, Philippines.

Technology development on eucalypts in the Philippines

One significant technology in plantation establishment of Eucalypts in the Philippines is the application of ectomycorrhiza in the nursery and in the field. One mycorrhizal tablet is inoculated to each container grown seedling in the nursery during seeding or pricking operation. This has been found successful for Eucalyptus species.

Experiments of de la Cruz and Aggangan (1990) in three nurseries located in very degraded and infertile grasslands in Luzon, Philippines showed that height and diameter growth of E. camaldulensis and E. deglupta increased by 21-32% and 10-30%, respectively due to seedling inoculation with mycorrhizal tablet (Figure 4). In the field, height growth of inoculated E. deglupta seedlings increased by as much as 15%; diameter by 51%; and volume by more than 154% relative to uninoculated plants. The positive response due to tablet inoculation in the nursery was observed even after three years in the field (Figures 4 and 5). Furthermore, mycorrhizal tablet inoculation was able to replace 60-85% of the inorganic fertilizers required for the growth of eucalypts in the field.

Figure 4. Effects of mycorrhizal tablet inoculation on height and diameter growth of Eucalyptus species in the nurseries of ANZAP, NIA and PICOP, Philippines

** Highly significantly different at the 1% confidence level as determined by the Duncan's Multiple Range Test.

ANZAP = ASEAN New Zealand Afforestation Project, Mayantoc, Tarlac, Philippines.

NIA = National Irrigation Administration, Pantabangan, Nueva Ecija, Philippines.

PICOP = Paper Industries Corporation of the Philippines, Surigao del Sur, Philippines.

Source: de la Cruz., Aggangan (1987)

Figure 5. Growth response of E. deglupta inoculated with mycorrhizal tablets 3 years after outplanting in PICOP, Philippines

ns = not significant
* = significant at the 5 % confidence level.
** = highly significant at the 1 % confidence level.
Source: de la Cruz., Aggangan (1987)

In another study by Aggangan et al. (1991), E. camaldulensis inoculated with ectomycorrhizal fungi, i.e. Pisolithus tinctorius, Rhizopogon sp., Sclerodermacitrinum, S. bovista and Cenococcum graniforme entrapped in alginate beads, showed an increase in height, diameter and biomass yield. Experiments revealed significant effect on height of E. camaldulensis one month after inoculation (Figure 6).

Findings also showed that younger cultures of C. graniforme are more effective than older ones. Seedlings inoculated with beads containing three month old mycelia gave the biggest diameter which was significantly better compared to those inoculated with seven month old culture or their uninoculated counterpart. In addition, seedlings inoculated with beads containing three month old mycelia gave significantly heavier biomass than those with beads containing seven month old mycelia. Biomass was increased by 33% relative to the uninoculated ones. The uninoculated seedlings gave the lightest biomass yield.

Likewise, E. camaldulensis inoculated by P. tinctorius entrapped in calcium alginate beads after two months stored at 4°C in either dry or suspended in sterile water conditions were significantly taller than uninoculated plants after one to two months in the nursery (Figure 6a-c).

Figure 6a. Monthly height and diameter growth of E. camaldulensis as affected by age of culture of C. graniforme entrapped in alginate beads

% I = % Increase
Source: Aggangan, N. et al., 1991

Figure 6b. Biomass and mychorrizal infection of E. camaldulensis as affected by age of culture of E. graniformis entrapped in alginate beads after 4 months in the nursery

Source: Aggangan, N. et al (1991)

Figure 6c. Periodic height growth of E. camaldulensis as affected by inoculation with mycelia of P. tinctorius entrapped in alginate beads and stored for two months at 4°C

** = highly significant at 1% confidence level

a = treatment means with the same letter are not significantly different from each other using DMRT.

Source: Aggangan, N. et al., 1991

On plantation establishment (Peñafiel and Bautista, 1987) reported a successful establishment of E. deglupta in grasslands dominated by Saccharum spontaneum and Imperata cylindrica through Taungya system. Taungya is among the variations of agroforestry system in which a short phase of food crop production is used as silvicultural method to ensure establishment of timber species. In 1983, two observation plots were established in the plantation of E. deglupta. One plot was for Taungya and the other was left uncultivated. Three years after the establishment of the plantation, the growth of bagras was observed as outstanding with an average total height growth of 5.22 m or an annual height growth of 1.74 m. For diameter growth, the E. deglupta trees had an average total of 6.10 mm or an annual diameter growth of 2.03 cm. Comparatively, the diameter and height growths of E. deglupta in plots without crop cultivation were only 4.08 cm (1.36 cm/yr) and 2.45 m (0.82 m/yr), respectively. E. deglupta under Taungya had also a high survival of 90.63% compared to only 53.13% for the E. deglupta without crop cultivation. At age three years, some of the E. deglupta trees in the Taungya plots were fruiting. Through this experiment, establishment of E. deglupta in grasslands could be successfully attained following the Taungya system. The E. deglupta trees benefited from cultivation and fertilization during each cropping. On the other hand, the cultivator benefited from the products obtained from the reforested area. In addition, it reduced the cost of weeding the plantation.

On the other uses of Eucalyptus (Zamora, 1986) found out that E. camaldulensis wood is a suitable substrate for shiitake mushroom. About 50 heads were harvested in the experimental logs.

CONCLUSION

Eucalyptus is not a new tree species in the Philippines. In fact, it has generally been accepted as one of the potential fast growing species for reforestation and source of wood to supply the heavily dependent wood industries of the country. But as it has appeared prominently on plantations, backyards, field boundaries, along roadsides several problems and intriguing questions have cropped up. Collectively, the experiences with Eucalyptus at the PFDPIN can provide some useful information. However, but more investigations should be done on the following:

• there is a scope of substantial site specific research in propagation techniques, nursery and plantation procedures to improve physical quality of plants, and find out effect on soil and water;

• better management design especially when mixed with other species;

• production of suitable techno-packages; and

• harvesting and marketing systems.

Ultimately, the sustainability of Eucalyptus plantations in the Philippines will depend not only in the technological innovations but also on the attitude of tree farmers towards the species. The development of Eucalyptus plantations is not to be projected as a panacea for all forest related economic and environmental ills, but to a certain extent it helps in the provision of healthful environment and provides additional source of income leading to a dignified and better life.

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