Planted Forests in Brazil

Manoel de Freitas

Abstract

This paper is about the importance of planted forests and based on the silvicultural evolution in Brazil. It includes technological processes and programs of forest establishment, such as: Genetic Improvement, Forest Management with their phases and strategies, operations related to planting, plantation reform and maintenance, taking in consideration their returns.

Forest harvesting aspects are also outlined, comparing mechanized system with the conventional one, since the latest is still widely used in Brazil, and considering the impacts of each one on costs and returns.

It is also stressed two important points: the relation between planted forests and environment which, lately, has increasingly got the society concern and the fact that these types of forest have, among others, the function of protecting and preserving such environment.

Social and economical aspects are equally discussed, showing planted forest benefits to people, as well as the programs that encourage the forest production throughout donation of seedlings to land-owners and giving support in the maintenance of their forests.

At last, various advantages of the industrial plantation are presented: direct and indirect social and environmental benefits, including, of course, the absorption of carbonic dioxide from the atmosphere and the utilization of degraded areas, inappropriate for other uses.

Concluding, it is recommended the divulgation and practicing of the reforestation due to the various mentioned aspects, mainly because planted forests are a renewable natural resource and their utilization can save natural forests.

Keywords: Eucalyptus, planted forests, reforestation.

Introduction

The first Eucalyptus plantations in Brazil aimed the production of firewood for locomotives and railway sleepers.

Due to its great diversity of species, easy adaptation to different places and present developed technology, Eucalyptus is, nowadays, an obligatory citation when talking about forest products of high efficiency and fast growth for different uses.

In this context some aspects concerning Eucalyptus planted forests at Champion Papel e Celulose Ltda., one of the largest pulp and paper mill of Brazil, will be covered referring to silvicultural evolution, genetic improvement, forest management, harvesting and environmental, economical and social benefits.

Brazil has reached significant increases in forest productivity , due to a careful work on genetic improvement, which has been developed mainly as from 1967. Earlier that date, mean annual increment (M.A.I.) was, in general, around 15m3/ha/yr at the age of 7 years old. By adopting more intensive silvicultural techniques (ground preparation, mineral fertilization, forest protection, etc.), production jumped to 21m3/ha/yr. By reintroducing new materials and a discerning choice of more adequate provenances associated to the evolution of genetic improvement programs, a level of 29 m3/ha/year were then reached (Figure 1).

Another strategy for forest improvement that has resulted in considerable gains is clonal selection, which looks for maximizing gains in just one generation.

Figure 1. Champion mean annual increment evolution.

Champion's Forest Genetic Improvement Program seeks to get superior genotypes (silviculturaly and technologically)suitable to various edaphoclimatic regions of Champion's lands. Strategies:

Sexual Program - from Seeds

Strategy

Seeds Improvement is distinguished among the

programs in process, once the generation of superior genotypes associated to the clonal techniques provides stable and efficient materials, adapted to several edaphoclimatic conditions.

Seeds selection is based on the "multipopulation" strategy, which basic principle is to use improved population with large genetic base and, sub-populations with potential genetic variability and adaptable to specific edaphoclimatic regions.

Asexual Program - Clonal Program

Strategy

The improvement traditional methods have used

superior phenotypes and have crossed these
individuals in order to obtain seeds. This method has allowed cumulative returns at each phase of selection without the risk of restricting the genetic base.

However, several years are needed to reach a high level of improvement with Eucalyptus spp population. With the new vegetative propagation techniques (macropropagation and micropropagation) it has been reached a significant time saving to get superior phenotypes and genotypes and to maximize productivity and forest products with high quality.

At Champion, asexual and sexual programs have been developed at the same time. See Figure 2.

Figure 2. Classical improvement and clonal program. Importance of genetic base maintenance.

Micropropagation and Genetic Improvement Program

Until 1986, clonal plant process and seedlings production for clonal trials were carried out through macropropagation. From that date, micropropagation has got increasing importance and from 1994 on, all clones from new selections have been tested in Clonal trials by this new method.

Micropropagation Advantages:

• Reversion to juvenility (reduction of clonal effect), increase of rooting capacity, greater photosynthetic efficiency;
• Increment increase;
• Genetic improvement program acceleration;
• Maintenance of superior genotypes in a small area of laboratory (clonal bank);
• Plants production for clonal garden.

Strategy Used to Produce the Species (Seed/Clone) to be Planted

Champion has different forest regions, each one with special edaphoclimatic characteristics.

Activities such as selection of the best parent trees, reversion to juvenility, evaluation of interaction genotype x environment for several different sites and spacing or approval of clones presenting high level of yield in pulp production have been accomplished by knowing edaphoclimatic conditions of each region where the Company works on.

All selection process have been conducted in accordance with a predetermined program seeking to get clones to attend clonal program, as showed on Figure 3.

Figure 3. Clonal program for commercial planting.

Forest Management

Champion forest management has been based on rational and organized forest utilization, in order to reach sustained production of the best quality wood at the lowest cost. To follow these principles, the management has been founded on edaphoclimatic studies and on using analytic techniques looking for alternatives that are more suitable to the organization purposes.

With this philosophy, Champion management forest priority is to grow wood causing less environmental impact possible, besides taking care of its resources potential productivity maintenance, keeping the maximum economic advantage.

Plantation Reform or Planting Plan

Champion wood supply strategy has been based on the classical concept of assuring self-sustainability, which is based on the stock at cutting average age (around 7 years).

Reforming after 1st Rotation or Carrying to 2nd Rotation

Wood pulp industries, mainly those using Eucalyptus species as raw-material, face, frequently, problems to decide between carrying to 2nd rotation and redoing a plantation just after the 1st cutting. Sometimes, the decision has been taken considering only production criteria, such as M.A.I. and individuals frequency per hectare, or qualitative criteria, such as undesirable trees to the mill process or land with production capacity poorly used.

Most of the times, the forest manager can not decide what alternative is the best by using only the volume criteria separately, since the production can vary in accordance with the species and place and, not always,the volume gain reached with forest replacement will be economically good.

So, it is necessary that the decision between carrying to 2nd rotation and reforming the plantation is also based on economic criteria, that considers production, costs and returns for delivering the wood at the mill, not only stumpage costs.

Methodology used to decide between an immediate new planting after 1st cutting and carrying to 2nd rotation takes in consideration elements that, direct or indirectly, contribute to the productivity increase, together with production, harvesting, transport and land costs compared to the purchasing of third parts wood delivered at the mill.

Nowadays, forest replacement through new planting assures a minimum gain of 20% compared to the prior plantings. It happens due to the use of improved genetic material(mainly clones), more efficient fertilization, soil enrichment techniques such as use of ash from biomass boiler and residues from mill clarifiers. So, the criterion used to analyze the viability of reforming a plantation takes in consideration:

• present M.A.I.,
• estimated M.A.I. if the forest went to a 2nd rotation;
• potential M.A.I. if the forest were reformed
• production costs, land use opportunity, cutting and transport costs and open market cost for delivered wood at the mill.

Planting/Reform - Usual Operations

Initial Ant Control:

1 man/day/ha and 1.5 kg of bait/ha

Cleaning (Sprouts elimination and spreading):

Productivity:

Sprouts cutting: 1 man/day/ha and 1.5 kg of bait/ha

Sprouts spreading:approx. 2h/ha (small tire tractor)

Ground Preparation:

Medium and heavy disking

Operation aiming to homogenize residues to reach a good level of ground preparation.

Productivity:

Valmet Tractor (big tire): 2h/ha

D-6 (Carterpillar Machine): 1.5h/ha

Bedding disking and fertilization

Productivity:

Bedding disking:

D-5 (Caterpillar Machine): 1.5 h/ha or Valmet Tractor 128: 2 h/ha

Fertilization:

Light disk: 1.2 h/ha (Small tire tractor)

Lining: 1.2 h/ha (Small tire tractor)

Planting: 2.5 men/day/ha

Irrigation:

Operation made only in dry seasons and consisting of application of 3 liters of water/tree around the seedling.

Productivity: 1 man/day/ha and 1h of small tire tractor/ha

Replanting

Weeding control:

Two manual weedings and two mechanical ones are foreseen.

Productivity estimated:

Manual weeding: 2 men/day/ha

Mechanical weeding: 1.2 h/ha (small tire tractor)

When possible, chemical weedings are also realized. Products used:

• Oxifluorfen: 1 liter/ha on the planting line (pre-emergent)
• Gliphosate in the hole area: 3.5 liters/ha

Mill residues:

Mill residues are applied using special equipment for this function.

Productivity:

Ash application: 1.5 h/ha, small tire tractor (3.5 ton at 1 year old)

Residues application: 3 h/ha, small tire tractor (10 ton just after planting)

Forest Maintenance along 2nd and 7th Year (Rotation Age)

Annual Ant Control:

Maintenance control is made after the 1st year, seeking to control the most important Eucalyptus forest plague: the leaf-eater ants (Atta sp).

Productivity: 10 ha/day/man

Maintenance Disking and Fire Control:

As from the second year disking using small tire tractors has been realized in all forests. This operation must be preferably realized at the end of the rain season, aiming mainly to break superficial capillarity, reducing water evaporation through the soil.

On property boundaries, where fire risk is high, annual disking has been made seeking mainly to reduce the combustible material.

Fertilization of 1st Year:

Forests are fertilized again in the 1st year, receiving, in accordance with the proposed site units (called Chemical Management Units), N-P-K or mill residues.

Coppice System

According to the used strategy to analyze management system: coppice or reforming just after one clear cutting, sometimes happen to decide for the coppice system, and then forest operations are the following:

Interplanting (or Planting in Small Spots to
Recover Failures):

The first fertilization and ant control should be made after harvesting. A survey to detect failure sopts is made three months after the cut. Then, when the failure spot is bigger than 12m x 12m, an interplanting is realized. So, the plantation is a combination of interplanted areas and coppicing.

Coppice Management:

When the forest is about 1 year old, it is realized a silvicultural operation which consists of eliminating shoots, reducing the competition.

The number of sprouts by stump varies from 1 to 3, according to the situation (failures, sprout vigor and others).

Forest Harvesting

CPC uses two basic systems for forest harvesting. At the first one, that is called "conventional" or "traditional" and which is still widely used in Brazil, the chain saw is the main equipment. At the second one, the activity is fully mechanized.

Harvesting Systems

Conventional or Traditional System:

• Pre-cutting inventory: gives the average volume per tree of the stand to be harvested and the volume of pulp wood and
• Harvesting planning: determines the number of rows for each cutterteam, cut down direction, entrance and exit for trucks, necessity of forwarding.
• Cutter team: 1 sawyer and 1 helper; Sawyer: tree bucking and crosscutting; Helper: debranch, pulp wood and energy wood pilings.
• Forwarding: made in places that were determined by planning, using small trucks and small loaders or self-loaders. Where forwarding is not necessary, transportation trucks go inside the stand.
• Average productivity: 5.6 m3/man/day

Mechanized System:

• Pre-cutting inventory: same as conventional system.
• Planning: determines cut down direction, hauling and wood processing zones. Since the majority of the areas is flat, planning is easy to be done.
• Equipments: scissors feller-buncher, skidder, chain-saw grapple adapted to a excavator
• System description:
• Tree falling and bundling: feller-buncher 28 m3/h
• Debranching: manual, using ax within the block 106 m3/man/day
• Hauling of the tree bundle to the processing zone: skidder
• Crosscutting trees in logs: chain-saw grapple adapted to an excavator.
• Productivity per module per month:
• 18,700 to 25,000 m3 (1st rotation)
• 11,300 to 15,000 m3 (2nd rotation)

Considerations

Conventional System x Mechanized System:

a) Comparing both harvesting systems, there is a reduction of 63% in manpower and 25% in cost.

b) Mechanized System productivity: 35.6 m3/ha/day

Outlook

• The scissors feller-buncher will be replaced by a disc-saw feller buncher adapted to a tracked hydraulical excavator.
• Total utilization of the tree, which would be chipping the material with a diameter below 6 cm in the forest, including branches and tops and using it to generate energy.

Planted Forests and the Environment

Forest standard adopted by Champion is allied to environmental silviculture, which looks for the harmony of the whole system as main aim. The programs in evolution are:

Flora

This program aims to gather native species of forest fragments, to maintain and to protect permanent preservation areas, to develop silvicultural standards for the re-establishment of native forests, recovering degenerated areas and accomplishing the portion of legal reserve.

Fauna

This project seeks to gather birds and animals that show up in Eucalyptus plantations and native forests, establishing correlation and, in the future, standardizing homogeneous plantations/native forests to improve the wildlife development.

Environmental Education

At this project differentiated education programs for the Company employees, public schools and regional community have been developed.

Forest Protection

Planted forest protection includes a special attention to the forests within the programs for entomological fauna control, biological control (creation of natural enemies) and phytossanity of forests.

Fishing and hunting are forbidden in forest areas all over the year.

Social and Economical Aspects of Planted Forests

Land-owners Assistance Program - CPC

Many land-owners are realizing that planting trees can be a good and profitable business. After all, the wood is becoming more and more difficult to be found and easier and easier to be sold.

Taking in consideration this aspect and many other advantages of planted forests Champion started its Land-Owners Assistance Program in 1960, which consists in donating high quality eucalyptus seedlings to the farmers besides giving them orientation on plating and free technical assistance. The main purpose of this program is to establish a regional forestry culture using areas degenerated by the traditional agriculture. Native species of the region and Eucalyptus are planted. This extension program total area is estimated in 40,000 ha, producing about 125,000 m3/year, equivalent to 8% of the total annual consumption of the mill.

Commercial Plantations Advantages

One of the most important advantages of planted forests is their higher economical utilization compared to tropical natural forests which major problem is the heterogeneity. There is no doubt that only planted forests using fast growth and highly productivity species can supply wood for industrial use, that has been required in increasing quantities.

Excluding the possibility of occurring a deep and delayed global resection, wood demand should exceed wood supplying in the medium term.

Unquestionably, future wood supplying, as well as the critical necessity of maintaining the balance of the vital ecological process in the ecosystems, will strongly depend on the continuous increase of planted forest areas.

Another interesting point to be discussed is the occupation of degraded lands, that due to their characteristics are not proper for agriculture or cattle raising, but are good for silviculture, where the tree planting, besides being possible, is, many times, recommendable. This definition is based on the fact that reforestation is the only activity that can be developed in any kind of soil, with no damage to it, but with the possibility of, in the areas where the soil is already degenerated by negligence or inappropriate use, recomposing and regenerating it.

The establishment of new plantations and the intensification of the management of the existing forests contribute to keep many regions economically alive, and, of course, to reduce CO2 growth rate in the atmosphere.

This latest impact has an increasing importance. By burning fossil fuel, CO2 existing in the atmosphere is growing at a rate that has been considered alarming by many scientists. Tropical forests reduction is an other reason for the increase of CO2 in the atmosphere. Industrial silviculture, based on sustainable production, contributes to reduce this effect.

Conclusion

This evaluation shows clearly that the forestry industry, as basic products supplier, is the economical pusher for the existing forests management and for new plantings.

It is a mistake to believe that forests can be largely planted and managed with no economical purpose. The only real way to do it is through rational utilization, that transforms silviculture in a self-sustainable economic activity.

On this matter, the forest industry position is very strong:

• Supply basic products, environmentally right, using raw-material that can be produced in a sustainable base.
• Final result of this industrial wood production is more forests, better and more robust forests.

Many people think that the best way to protect the nature and plan for future generations is to reduce theconsumption. This can be true when talking about not renewable resources. But when we talk about products of the industry based on wood, it seems that the best advice would be the opposite. The more paper and wood consumption the better will be the support and incentive to the management of the existing forests and to new plantings. Specially developing countries, with great areas that need to be planted, can take advantage of this advice, which would help stopping the continuous destruction of their forests.

References

Lima, W.P., 1993: Impacto Ambiental do Eucalipto. 2nd. Ed., Edpus, São Paulo, 301 p.