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Revista de Economia e Sociologia Rural

versão impressa ISSN 0103-2003versão On-line ISSN 1806-9479

Rev. Econ. Sociol. Rural v.40 n.3 Brasília  2002

http://dx.doi.org/10.1590/S0103-20032002000300004 

Economic profitability analysis of reforestation with native trees: the state of São Paulo's case1

 

 

José Arimatéia Rabelo MachadoI; Carlos José Caetano BachaII

IResearcher at Instituto Florestal, Caixa Postal 372, Cep 17001-970, Bauru, SP, Brasil
IIAssociate Professor at ESALQ - USP, Avenida Pádua Dias, 11 - Caixa Postal 9, Cep 13418-900, Piracicaba, SP, Brazil

 

 


ABSTRACT

This paper analyzes the economic profitability of native-tree reforestation for the production of sawlogs. The projects evaluated are experimental rather than commercial and are located in the Brazilian state of São Paulo. These experimental plots were reforested with the native tree species Centrolobium tomentosum ("araruva"), Balforodendron riedelianum ("pau-marfim") and Araucaria angustifolia ("pinheiro-brasileiro"), recommended for their economic value by a previous evaluation of long-term native-tree reforestation. Economic profitability analyses were made under both deterministic and risk conditions using data from the reforestation experiments. It was found that all the experiments would be profitable. This paper concludes with the suggestion that new research needs to be conducted to improve the genetic material used for reforestation, as superior stock would increase productivity and promote consistent economic profitability.

Key words: Brazilian native trees, profitability, reforestation


 

 

1. Introduction

This paper analyzes the economic profitability of reforestation using native trees to produce roundwood for sawlogs. The state of São Paulo is taken for analysis because the state’s Forest Institute conducted and published the results of several successful reforestation experiments.

Generally, Brazilian public and private programs geared to stimulate reforestation for the production of roundwood2 have centered their attention on pure plantings of exotic species, for example eucalyptus and pinus. Though, small-scale plantings of native trees have been carried out, especially for conservation purposes, such as the recovery of watersheds, little attention has been paid to reforestation with native trees to produce roundwood. However, this type of reforestation project can supply specific wood markets that are now supplied with roundwood obtained from the unsustainable exploitation of natural forests.

Currently, experiments to assure the technical viability of reforestation using native trees are being conducted. Gurgel Filho et al. (1978) analyzed nine forestry experiments over more than two decades. Their work evaluated the forest’s features and the biometric growth of native trees from Brazil’s more temperate zone planted in pure stands in the state of São Paulo’s northeast. The authors’ concluded that as soil fertility and climatic conditions improved, tree growth increased. Due to their long, commercially useful trunk and lack of heavy bark, the following tree species were found to be most economically viable: Centrolobium tomentosum ("araribá amarelo" or "araruva"), Balfourodendron riedelianum ("pau-marfim"), and Araucaria angustifolia ("pinheiro brasileiro").

Some years latter, Gurgel Filho et al. (1982) published the results from seven native-tree planting experiments conducted over twenty years. The analyzed variables were growth in length and diameter at breast height (DBH). These plantings were established in Santa Rita do Passa Quatro, a city located in northeastern São Paulo. The species with the greatest increase in length were Joannesia princeps ("anda-açú"), Piptadenia macrocarpa ("angico do cerrado"), and Cedrela fissilis ("cedro"). The authors did not evaluate the economic viability of any pure native specie plantation; however, if this evaluation were carried out using the authors’ 1978 criteria, the three tree species cited in the previous sentence would be recommended.

Over almost 20 years, Garrido et al. (1990) examined the forest features of five native species planted in Assis, a city in southwestern São Paulo. The forests were both pure and mixed plantings. Based on these experiments and other studies, the authors recommend Anadenanthera falcata ("angico") as an appropriate tree for producing fence posts and electrical service poles. Though their work did not address the economic profitability of reforestation with native trees, it was the first to determine the five studied species’ heartwood to sapwood ratio. Based on this ratio, the authors also recommended planting Colubrina glandulosa ("saguaragi") and Gochnatia polymorpha ("cambará") on plantations producing fence post timber. Though there have been other published studies addressed to reforestation with native trees, these studies were not from projects as long-term as those previously referred to.

Several studies have evaluated the economic profitability of commercial plantations of exotic trees, such as pine and eucalyptus. Among these works, Capp Filho (1976), Berger (1979), and Veiga Filho & Veiga (1994) analyzed the economic profitability of exotic tree plantations established during the 1965 to 1988 Brazilian Program of Fiscal Incentives for Afforestation and Reforestation.

 

2. Methodology and data source

Chart 1 gives information about the experimental pure plantings of native trees in the state of São Paulo. These plantings can produce roundwood for different economic purposes.

Of the experiments listed in Chart 1, only Gurgel Filho et al.’s 1978 study was selected for analysis. It provides enough data to calculate economic profitability indicators of three tree species that can produce sawlogs: Araucaria Angustifolia ("pinheiro-brasileiro"), Centrolobium tomentosum ("araribá amarelo" or "araruva"), and Balfourodendron riedelianum ("Pau-marfim"). Gurgel Filho et al.’s 1982 study does not contain enough information for the calculation of economic profitability, and Garrido et al.’s 1990 study analyzed trees that only produce utility poles, fence posts, and firewood, which are not the focus of our paper.

 

Chart 1 - Click to enlarge

 

2.1. Features of the native trees examined in this paper

According to Carvalho (1994), Araucaria Angustifolia ("pinheiro-brasileiro") is a promising, woody tree. Although its wood is of low density (0.55 g/cm3) and low durability when exposed to weather, its is appropriate for use in ceilings, as framing and lathing, and for the manufacture of broomsticks, crates, toys, furniture frames, matches, ice cream sticks, pencils, spools, among other products (Lorenzi, 1992). Carvalho (1994) also concluded that Araucaria Angustifolia wood is of excellent quality for general civil construction, crates, furniture, and veneers.

Carvalho (1994) also classified Centrolobium tomentosum ("araribá amarelo" or "araruva") as a promising source of wood. Its timber has attractive heartwood, is of low high-density (0.75 g/cm3), can be easily sawn, and is composed of hard fibers that are durable in all weather conditions (Lorenzi, 1992). It can be used to produce parquet flooring, fine furniture, poles, fence posts, civil construction material (bridging), fences, airplane propellers, tool handles, and barrels. It can also be used in naval and hydrologic constructions and for doors, cabinetry, ceilings, and wagons.

Balfourodendron riedelianum ("Pau-marfim") is a potentially very useful tree (Carvalho, 1994). According to Lorenzi (1992), Pau-marfim is of medium high-density (0.84 g/cm3). It is hard but has little resistance to insects and can deteriorate rapidly when exposed to inclement weather. It is recommended for the production of fine furniture, indoor frames, doors, ornamental veneers, civil construction, shoe lasts, billiard cues, tool handles, cabinetry, and ceilings.

2.2. The life cycle of trees, cash flows, and methods for analyzing economic profitability

Each of the three native tree species chosen for analysis each requires 25-years between planting and the final clear-cut harvest of sawlogs. Some thinning takes place over the growth period, which produces firewood and fence posts. Pinheiro-brasileiro is thinned four times, pau-marfim is thinned five times, and araruva is thinned six times; however, the revenues from these intermediate cuts are miniscule when compared with the revenues obtained from the final clear-cut.

Land costs (for projects identified with number 1 or 4) and other expenses incurred at the time of project initial installation (such as seedling, insecticides, and services provided by others3) are considered investment expenses. Operational expenses are considered to be for continued pesticides application and other services, such as for cleaning the "streets" that divide the stands. The greatest operational expenses are incurred in the first three years after planting; from the fourth year to 25th year, operational expenses are very small.

For analytical purpose, the following choices are considered in our analysis of economic profitability: a) farmers buying seedlings or the government granting seedlings to the farmers; b) farmers buying or renting land for reforestation purposes; c) land cost is omitted from the analysis. The letters ‘A," "P," and "M" are used to identify the type of tree planted on an experimental plot: "A" signifies "araruva", "P" signifies "pinheiro-brasileiro," and "M" signifies "pau-marfim." Following each letter, there is a number ranging from 1 to 6. Numbers 1, 2, and 3 identify the cases where farmers buy seedlings; and numbers 4, 5, and 6 identify the cases where the government grants seedlings to the farmers4. Moreover, the plantation’s major expense, land, is included in the analysis of projects identified with a 1, 2, 4, or 5: projects identified with a 1 or a 4 include the cost of land purchase; projects identified with a 2 or 5 include the cost to rent land. Projects identified with a 3 or 6 exclude the cost of land. In total, eighteen projects can be analyzed. These projects are shown in Chart 2.

 

Chart 2 - Click to enlarge

 

Because entrepreneurs have little difficulty interpreting internal rate of return (IRR) values, this profitability measure has become the most commonly employed. IRR is the discount rate that makes the present value of a net cash flow equal to zero (Noronha, 1987). A project is economically viable when the IRR is greater than the opportunity cost of capital. Pure investment projects have a unique IRR value; otherwise, there are several IRR. IRR is calculated by using the following formula:

Where: r is a discount rate, and Bi and Ci are, respectively, the values of receipts and cost at time i.

According to Noronha (1987), IRR offers two major advantages over other profitability measures. First, it is calculated by using only the cash flow. It is not necessary to assume a priori some rate for measuring the opportunity cost of capital. Second, IRR can be compared directly with any opportunity cost rate or other econometric measure representing a financial application in the market.

On the other hand, Azevedo Filho (1995) considers that a project’s present value (PV) is the most consistent indicator for evaluating an investment project under deterministic conditions. PV is calculated using the following equation:

When a project shows a negative PV, it will be refused. By using the above formula, the higher the opportunity cost of capital, the less attractive a project becomes, independent of the payment capacity of a firm. According to Faro (1972), the ranking of several projects by PV depends on the interest rate chosen as opportunity cost, as a project’s present value is altered by interest rates changes.

According to Rodriguez et al. (1997), the Faustmann formula, which appeared in 1849, is appropriate for the evaluating forestry projects. The Faustmann formula, also called the expected value of land (EVL), is appropriate for the evaluation of projects that that are perpetually repeated. A forestry project is considered economically viable if EVL is greater than the acquisition cost of land (ACL). The higher the EVL/ACL ratio, the more attractive the investment project. According to Clutter et al. (1983), EVL can be calculated by using the following formula:

Where: EVL is the expected value of land; RLt is the net receipt capitalized at the end of each productive cycle; t is the duration of each productive cycle; and, j is the rate of opportunity cost of capital.

2.3. Deterministic analysis, scenario creation, and Monte Carlo simulation

Our analyses of the economic profitability of native-tree reforestation are made under both deterministic and risk conditions. Under deterministic conditions, the values of variables are assumed to be well known. Under risk conditions, the variables values are uncertain; hence, a probabilistic distribution of these values is assumed.

In order to perform our deterministic analysis, historical information from field experiments and complementary technical information were gathered. Prices of raw materials and wooden products are from March 1999. The variables price of goods, cost of production, and productivity are central in the determination of economic profitability. Because of this, six scenarios are created to evaluate the change in reforestation project economic profitability when these variables’ values change:

• Optimistic scenario 1 (OS1): productivity increases due to the use of improved seedlings and a more rational, appropriate planting technique;

• Optimistic scenario 2 (OS2): the price of logs increases due to the plantation’s environmental certification;

• Optimistic scenario 3 (OS3): the price of logs falls due to an expansion of reforestation in a broader area where the price of land is lower than at the original site of the experiments, though there is no change in productivity;

• Optimistic scenario 4 (OS4): costs fall due to the use of improved seedling germination technology;

• Pessimistic scenario 1 (PS1): the price of log falls due to a reduction in transportation cost for competing producers in other states, one of several factors that alter the price of logs. In this paper, the cost of road transportation from Sinop-MT to Santa Rita do Passa Quatro-SP was used in the calculation of log prices; and

• Pessimistic scenario 2 (PS2): a reduction in the price of logs due to use of genetically inferior rootstock.

ALEAXPRJ5 software is used to perform the Monte Carlo simulation. This software permits the analysis of complex problems involving random variables in the condition of risk. According to Takitane (1988), "among the contributions of this software, there is the knowledge of a unique condition of projects that usually have multiple internal rates of return."

Due to a lack of information about the probabilistic distribution of the reforestation project’s random variables, a triangular distribution is used. A triangular distribution allows flexibility in regards to the random variables’ level of asymmetry. The distribution is defined by the mode (m), minimum (a), and maximum (b) x-variable values. In this paper, the mode is assumed to equal the average, and the likelihood is defined as L{a<x<b} = 1.

A triangular distribution is assumed for the following variables: price of firewood, price of fence posts, price of sawlogs, production of firewood, production of fence posts, production of sawlogs, implantation cost, maintenance costs, price of bare land for reforestation purposes, and cost to rent land for reforestation purposes.

There is also a lack of information about the native tree species considered in this paper. Due to this, estimates of the random variables’ probabilistic distributions were based on available information for other tree species. The following is assumed:

• the prices of firewood and fence posts are based on the prices charged for the same products made from eucalyptus wood;

• the minimum and maximum sawlog values are based on fluctuations observed for native tree sawlog prices in the state of Pará from 1974 to 1999. This average price is also used in the deterministic analysis;

• the average values used for firewood production, fence post production, sawlog production, implantation cost, and maintenance cost are the same as those from the deterministic analysis. The minimum and maximum values of these variables are based on the data from a eucalyptus plantation and from the possible scenarios; and,

• the price of bare land for reforestation purposes and the value of rent are based on values calculated for land in the state of São Paulo (from 1974 to 1999) by the São Paulo State Institute of Agricultural Economics (Instituto de Economia Agrícola, IEA).

 

3. Results and discussion

This section is divided into three parts. The first (3.1) is a discussion of the results from deterministic analysis (sub item 3.1). The second part (3.2) gives the results from the six scenarios outlined in the prior section: scenarios OS 1 to 4 and PS 1 & 2. Finally, the third part (3.3) shows the Monte Carlo Simulation results for the projects identified in Chart 2.

3.1. Results from deterministic analysis

Table 1 shows the present value (PV) for all projects identified in Chart 2 that consider land costs. Different opportunity costs were considered, ranging from 6% to 20% per year6. Reforestation projects that show a negative PV are refused. It can be observed that project present values change according to the opportunity cost considered, causing the ordering of projects as determined by economic viability to change.

 

Table 1 - Click to enlarge

 

When the interest rate is 6% per year, all native-tree reforestation projects are economically viable because all their present values are greater than zero. Three criteria appear to determine the ranking of projects according to economic viability: tree specie, use of purchased or donated seedlings, and land cost. According to the specie criterion, the most viable projects are the ones that use "araruva" trees (A), followed by projects that use "pinheiro-brasileiro" (P) and "pau-marfim" (M). Projects that make use of donated seedlings (projects with the numbers 4 and 5) are economically more viable than projects that make use of purchased seedlings (projects 1 and 2). Finally, projects on land owned by the farmer (projects with the numbers 1 and 4) show a higher PV than the ones in which the farmer rents the land (projects with the numbers 2 and 5).

An increase in the opportunity cost of capital, however, causes some alterations in the selection and ordering of the reforestation projects. When the interest rate reaches 9% per year, the first project is rejected: project M1. At higher interest rates, the projects are ranked, from best to worst, 5, 2, 4, and 1. All projects are refused when the interest rate reaches 15% per year. Projects that make use of donated seedlings are always preferable to projects in which farmers buy seedlings; in other words, project M4 is preferable to M1, M5 is better than M2, P4 is preferable to P1, P5 is better than P2, A4 is preferable to A1, and A5 is better than A2. Moreover, reforestation projects that make use of seedlings granted by the government keep a positive present value even when opportunity costs are 1 to 3 percentage points above the opportunity cost level that turns PV negative for projects that make use of purchased seedlings.

By analyzing cash flows of the projects identified in Chart 2, it is possible to state that they are non-conventional7; therefore, caution is need in the evaluation of these projects using their internal rates of return (IRR). However, there is no change in the sign (positive or negative) of the non-recovered capital balance. In other words, the projects are pure investments, hence, have a unique IRR. Table 2 shows the IRR for reforestation projects shown in Chart 2.

 

Table 2 - Click to enlarge

 

Comparing IRR values with the opportunity costs used in the calculation of PV, it can be observed that that both methods of project evaluation, IRR and PV, refuse the same projects. However, the ordering of projects according to IRR is not the same as when ordered according to PV.

Table 3 shows the expected value of land (EVL) for projects that do not take into account land cost: projects with the numbers 3 and 6 in Chart 2. For comparative purposes, a pure eucalyptus project (E1) was added to Table 3. Projects that have an EVL less than the cost of land acquisition (R$ 1,652.89/ha) are refused.

 

Table 3 - Click to enlarge

 

 

Table 4 - Click to enlarge

 

 

Table 5 - Click to enlarge

 

Except for project E1, the ordering of projects is determined by two criteria: specie planted and purchased or donated seedlings. According to the specie criterion, the best projects are the ones that use "araruva" trees (A), followed by those that use "pinheiro-brasileiro" trees (P) and "pau-marfim" (M). According to the seedling donation/purchase criterion, projects in which the farmers receive free seedlings (projects with the number 6) are economically superior to the ones in which farmers buy seedlings (projects with the number 3).

All reforestation projects are economically viable when the opportunity cost is 6% per year or less. As interest rates increase, the first project refused is M3. At or above a 12%/year interest rate, the EVL of all projects is less than the ACL (average cost of land); thus, all reforestation projects are refused (including E1). Table 3 shows that as interest rates increase to 12%, the EVL of the eucalyptus project (E1) generally becomes more attractive than the EVL for the projects using native trees, though the EVL of all projects decreases. When the interest rate is 6% to 7% per year, project E1’s EVL is greater than only project M3’s. When the interest rate ranges from 8% to 9% per year, project E1’s EVL is greater than that of projects M3, M6, and P3. When the interest rate is 10% per year, only project A6’s EVL is greater than project E1’s. When interest rate is 11% per year, E1 project is refused but project A6 is still accepted.

3.2 Results from scenarios

Chart 3 shows estimates of present value (PV) and internal rate of return (IRR) for eighteen scenarios created by conditioning projects M1, P1, and A1 with assumptions OS 1 thru 4 and PS 1 & 2. The chart also presents the percentile change of variables PV and IRR from their values in the earlier deterministic analysis. Among the optimistic scenarios, OS1 (which assumes a productivity increase due to improved root stock and more rational, appropriate tree planting techniques) shows the largest positive percentile change of PV and IRR from the values arrived at in the deterministic analysis. Among the pessimistic scenarios, PS2 (the price of logs falls because genetically inferior root stock is planted) shows the largest reduction of PV and IRR from the values arrived at in the deterministic analysis.

 

Chart 3 - Click to enlarge

 

The results from the scenarios conditioned by OS1 and PS2 show the importance of genetic factors to tree productivity and log value, which suggests that genetic improvement increases native tree reforestation project profitability.

3.3. Results from Monte Carlo simulation

Despite the lack of information about reforestation with native trees, the Monte Carlo method permits a more sophisticated analysis of a reforestation project’s economic profitability. In the following analysis, opportunity cost is considered to be 6% per year while the limit values8 (LV) for each variable are the same as those from the deterministic analysis of projects A1, P1 and M1.

Tables 3 through 5 give the present value (PV) and internal rates of return (IRR) of the various projects under risk conditions. It can be observed that reforestation with native trees is more attractive when PV and IRR are calculated under risk conditions than under deterministic conditions. The 6th column of Tables 3, 4, and 5 shows the likelihood of the average PV and IRR calculated under risk conditions being above the limit value calculated in the deterministic analysis. It can be seen that these likelihoods are high, and they are greater for PV than for IRR because the chosen value for the opportunity cost of money is low (6%/year).

In order to compare the results found in this paper with the results presented by other authors, one can examine project M3 in Table 4 and project A6 in Table 3. Both projects M3 and A6 ignore the cost of land, but in project M3 farmers buy seedlings while in project A6 the seedlings are donated by the government. Internal rates of return are 15.2% and 22.2% for projects M3 and A6 respectively, and their standard deviations are 1.3 and 1.5 percentage points respectively. These values for IRR and standard deviation are close to or better than those from some of the other agricultural activities listed in Chart 4, leading to the conclusion that reforestation with native trees is an attractive agricultural investment, especially if "araruva" trees are planted.

 

Chart 4 - Click to enlarge

 

In general, economic profitability indicators IRR and PV show that reforestation projects with native trees are profitable, whether calculated under deterministic or risk conditions. Reforestation projects, however, often suffer through several years of negative cash flow, which is considered a disadvantage by some investors. This inconvenience can be ameliorated by staggering plantings to create a positive annual cash flow9.

 

4. Conclusion

This paper analyzed the economic profitability of sawlog production from several experimental native-tree reforestation projects in the state of São Paulo, Brazil. Profitability was determined through both deterministic and risk analyses.

The deterministic analysis was conducted in two phases. The first phase considered just one productive cycle with present value (PV) and internal rate of return (IRR) used as profitability measures. The second phase considered perpetual productive cycles, and the expected value of land (EVL) was used as the profitability measure. In the first phase, all reforestation projects are economically viable when interest rates are below 8% per year. When interest rates range from 8% to 15% per year, only some projects remain economically viable. When interest rates are above 15% per year, all projects become unprofitable. In the second phase, all projects are refused when interest rates are above 12% per year. From these results, it can be stated that reforestation projects with native trees are economically viable if interest rates are not high.

The risk analysis was also performed in two phases: first, scenarios were created; second, the Monte Carlo method was applied. According to results from the scenarios, the variables productivity and log price have the most influence on PV and IRR. Because tree productivity and log price are greatly influenced by the saplings genetic material, it is clear that investment in forestry research, especially genetic improvement, is the linchpin to increasing the profitability of pure native-tree plantings. Without this type of investment, environmental certification, seedling donation, and other reforestation incentives will do little to increase the number or profitability of native-tree reforestation projects.

Internal rates of return from the Monte Carlo simulations of projects M3, A3, and P3 are noteworthy: 15.2%, 16.9%, and 17% respectively. These projects do not take into account the cost of land but do consider the cost of seedlings. Because of this conditioning, these projects compared favorably with other agricultural projects (Chart 4), showing that investment in native-tree reforestation projects should be as profitable as investment in alternative agricultural endeavors.

However, profitability is not the only factor considered when making business decisions. Full economic payback from investments in native-tree reforestation projects comes only after the clear-cut for sawlogs, a minimum of 25 years after the initial investment, which makes this type of investment extremely illiquid. Moreover, the projects cannot be adapted to changing social or environmental conditions, making the investment relatively inflexible. As there is no methodology for evaluating the benefits of flexibility, the economic costs of business inflexibility cannot be measured.

Reforestation with native trees is an economically justified land use option for fallow land on small and medium sized farms. An increase in the number of small native-tree reforestation projects in southeastern and southern Brazil can assure a stable supply of this type of timber while reducing the demand for native trees from the environmentally sensitive Amazon Region.

It is important to note that all projects analyzed in this paper are field experiments. Before large-scale commercial native-tree reforestation projects can justifiably be initiated, more forestry research needs to be conducted. There is also a need to experiment with innovative tree farming systems—such as planting several stands at different times and combining timber with fodder and food crops—to make reforestation investments more liquid and flexible.

 

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1 This paper bases on the first's autor M.Sc. Dissertation, what was advised by the second author
2For firewood, charcoal and logs.
3Such as plowing, harrowing, pitting, planting and control of ants.
4It is the case where there is a program for fostering tree planting.
5In order to obtain more information about this software, see Azevedo Filho, 1988. ALEAXPRJ - Sistema para Simulação e Análise Econômica de Projetos em Condições de Risco: manual do usuário. USP/PCP/CIAGRI - 1988. 43p.
6An interest rate equal to 6% per year is obtained with the safest financial investment, i.e., a bank savings account. An interest rate equal to 20% per year was the highest interest rate offered by the Brazilian Treasury when selling public bonds (except to avoid capital flight during international financial crises).
7A non-conventional project is one where the net cash flows change their signs more than one time during the life period of project. In other words, net cash flows are negative during some years, turning positive in a specific year, and turning again to negative for several years, then turning positive, and so on. The last net cash flow is positive.
8LV is a reference.
9The experiments showed at this paper refer to one hectare. Hence, several stands can be planted in different years, permitting each year to have some receives.

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