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Forestry—A Definition

For the purposes of the present chapter, forestry is understood to embrace all the fieldwork required to establish, regenerate, manage and protect forests and to harvest their products. The last step in the production chain covered by this chapter is the transport of raw forest products. Further processing, such as into sawnwood, furniture or paper is dealt with in the Lumber, Woodworking and Pulp and paper industries chapters in this Encyclopaedia.

The forests may be natural, human-made or tree plantations. Forest products considered in this chapter are both wood and other products, but emphasis is on the former, because of its relevance for safety and health.

Evolution of the Forest Resource and the Sector

The utilization and management of forests are as old as the human being. Initially forests were almost exclusively used for subsistence: food, fuelwood and building materials. Early management consisted mostly of burning and clearing to make room for other land uses—in particular, agriculture, but later also for settlements and infrastructure. The pressure on forests was aggravated by early industrialization. The combined effect of conversion and over-utilization was a sharp reduction in forest area in Europe, the Middle East, India, China and later in parts of North America. Presently, forests cover about one-quarter of the land surface of the earth.

The deforestation process has come to a halt in industrialized countries, and forest areas are actually increasing in these countries, albeit slowly. In most tropical and subtropical countries, however, forests are shrinking at a rate of 15 to 20 million hectares (ha), or 0.8%, per year. In spite of continuing deforestation, developing countries still account for about 60% of the world forest area, as can be seen in table 1. The countries with the largest forest areas by far are the Russian Federation, Brazil, Canada and the United States. Asia has the lowest forest cover in terms of percentage of land area under forest and hectares per capita.

Table 1.  Forest area by region (1990).

Region                                  

  Area (million hectares)         

 % total   

Africa

536

16

North/Central America

531

16

South America

898

26

Asia

463

13

Oceania

88

3

Europe

140

4

Former USSR

755

22

Industrialized (all)

 1,432

42

Developing (all)

 2,009

58

World

 3,442

100

Source: FAO 1995b.

Forest resources vary significantly in different parts of the world. These differences have a direct impact on the working environment, on the technology used in forestry operations and on the level of risk associated with them. Boreal forests in northern parts of Europe, Russia and Canada are mostly made up of conifers and have a relatively small number of trees per hectare. Most of these forests are natural. Moreover, the individual trees are small in size. Because of the long winters, trees grow slowly and wood increment ranges from less than 0.5 to 3 m3/ha/y.

The temperate forests of southern Canada, the United States, Central Europe, southern Russia, China and Japan are made up of a wide range of coniferous and broad-leaved tree species. Tree densities are high and individual trees can be very large, with diameters of more than 1 m and tree height of more than 50 m. Forests may be natural or human-made (i.e., intensively managed with more uniform tree sizes and fewer tree species). Standing volumes per hectare and increment are high. The latter range typically from 5 to greater than 20 m3/ha/y.

Tropical and subtropical forests are mostly broad-leaved. Tree sizes and standing volumes vary greatly, but tropical timber harvested for industrial purposes is typically in the form of large trees with big crowns. Average dimensions of harvested trees are highest in the tropics, with logs of more than 2 m3 being the rule. Standing trees with crowns routinely weigh more than 20 tonnes before felling and debranching. Dense undergrowth and tree climbers make work even more cumbersome and dangerous.

An increasingly important type of forest in terms of wood production and employment is tree plantations. Tropical plantations are thought to cover about 35 million hectares, with about 2 million hectares added per year (FAO 1995). They usually consist of only one very fast growing species. Increment mostly ranges from 15 to 30 m3/ha/y. Various pines (Pinus spp.) and eucalyptus (Eucalyptus spp.) are the most common species for industrial uses. Plantations are managed intensively and in short rotations (from 6 to 30 years), while most temperate forests take 80, sometimes up to 200 years, to mature. Trees are fairly uniform, and small to medium in size, with approximately 0.05 to 0.5 m3/tree. There is typically little undergrowth.

Prompted by wood scarcity and natural disasters like landslides, floods and avalanches, more and more forests have come under some form of management over the last 500 years. Most industrialized countries apply the “sustained yield principle”, according to which present uses of the forest may not reduce its potential to produce goods and benefits for later generations. Wood utilization levels in most industrialized countries are below the growth rates. This is not true for many tropical countries.

Economic Importance

Globally, wood is by far the most important forest product. World roundwood production is approaching 3.5 billion m3 annually. Wood production grew by 1.6% a year in the 1960s and 1970s and by 1.8% a year in the 1980s, and is projected to increase by 2.1% a year well into the 21st century, with much higher rates in developing countries than in industrialized ones.

Industrialized countries’ share of world roundwood production is 42% (i.e., roughly proportional to the share of forest area). There is, however, a major difference in the nature of the wood products harvested in industrialized and in developing countries. While in the former more than 85% consists of industrial roundwood to be used for sawnwood, panel or pulp, in the latter 80% is used for fuelwood and charcoal. This is why the list of the ten biggest producers of industrial roundwood in figure 1 includes only four developing countries. Non-wood forest products are still very significant for subsistence in many countries. They account for only 1.5% of traded unprocessed forest products, but products like cork, rattan, resins, nuts and gums are major exports in some countries.

Figure 1.  Ten biggest producers of industrial roundwood, 1993 (former USSR 1991).

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Worldwide, the value of production in forestry was US$96,000 million in 1991, compared to US$322,000 million in downstream forest-based industries. Forestry alone accounted for 0.4% of world GDP. The share of forestry production in GDP tends to be much higher in developing countries, with an average of 2.2%, than in industrialized ones, where it represents only 0.14% of GDP. In a number of countries forestry is far more important than the averages suggest. In 51 countries the forestry and forest-based industries sector combined generated 5% or more of the respective GDP in 1991.

In several industrialized and developing countries, forest products are a significant export. The total value of forestry exports from developing countries increased from about US$7,000 million in 1982 to over US$19,000 million in 1993 (1996 dollars). Large exporters among industrialized countries include Canada, the United States, Russia, Sweden, Finland and New Zealand. Among tropical countries Indonesia (US$5,000 million), Malaysia (US$4,000 million), Chile and Brazil (about US$2,000 million each) are the most important.

While they cannot be readily expressed in monetary terms, the value of non-commercial goods and benefits generated by forests may well exceed their commercial output. According to estimates, some 140 to 300 million people live in or depend on forests for their livelihood. Forests are also home to three-quarters of all species of living beings. They are a significant sink of carbon dioxide and serve to stabilize climates and water regimes. They reduce erosion, landslides and avalanches, and produce clean drinking water. They are also fundamental for recreation and tourism.

Employment

Figures on wage employment in forestry are difficult to obtain and can be unreliable even for industrialized countries. The reasons are the high share of the self-employed and farmers, who do not get recorded in many cases, and the seasonality of many forestry jobs. Statistics in most developing countries simply absorb forestry into the much larger agricultural sector, with no separate figures available. The biggest problem, however, is the fact that most forestry work is not wage employment, but subsistence. The main item here is the production of fuelwood, particularly in developing countries. Bearing these limitations in mind, figure 2 below provides a very conservative estimate of global forestry employment.

Figure 2.  Employment in forestry (full-time equivalents).

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World wage employment in forestry is in the order of 2.6 million, of which about 1 million is in industrialized countries. This is a fraction of the downstream employment: wood industries and pulp and paper have at least 12 million employees in the formal sector. The bulk of forestry employment is unpaid subsistence work—some 12.8 million full-time equivalents in developing and some 0.3 million in industrialized countries. Total forestry employment can thus be estimated at some 16 million person years. This is equivalent to about 3% of world agricultural employment and to about 1% of total world employment.

 

In most industrialized countries the size of the forestry workforce has been shrinking. This is a result of a shift from seasonal to full-time, professional forest workers, compounded by rapid mechanization, particularly of wood harvesting. Figure 3 illustrates the enormous differences in productivity in major wood-producing countries. These differences are to some extent due to natural conditions, silvicultural systems and statistical error. Even allowing for these, significant gaps persist. The transformation in the workforce is likely to continue: mechanization is spreading to more countries, and new forms of work organization, namely team work concepts, are boosting productivity, while harvesting levels remain by and large constant. It should be noted that in many countries seasonal and part-time work in forestry are unrecorded, but remain very common among farmers and small woodland owners. In a number of developing countries the industrial forestry workforce is likely to grow as a result of more intensive forest management and tree plantations. Subsistence employment, on the other hand, is likely to decline gradually, as fuelwood is slowly replaced by other forms of energy.

Figure 3Countries with highest wage employment in forestry and industrial roundwood production (late 1980s to early 1990s).

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Characteristics of the Workforce

Industrial forestry work has largely remained a male domain. The proportion of women in the formal workforce rarely exceeds 10%. There are, however, jobs that tend to be predominantly carried out by women, such as planting or tending of young stands and raising seedlings in tree nurseries. In subsistence employment women are a majority in many developing countries, because they are usually responsible for fuelwood gathering.

The largest share of all industrial and subsistence forestry work is related to the harvesting of wood products. Even in human-made forests and plantations, where substantial silvicultural work is required, harvesting accounts for more than 50% of the workdays per hectare. In harvesting in developing countries the ratios of supervisor/technician to foremen and to workers are 1 to 3 and 1 to 40, respectively. The ratio is smaller in most industrialized countries.

Broadly, there are two groups of forestry jobs: those related to silviculture and those related to harvesting. Typical occupations in silviculture include tree planting, fertilization, weed and pest control, and pruning. Tree planting is very seasonal, and in some countries involves a separate group of workers exclusively dedicated to this activity. In harvesting, the most common occupations are chain-saw operation, in tropical forests often with an assistant; choker setters who attach cables to tractors or skylines pulling logs to roadside; helpers who measure, move, load or debranch logs; and machine operators for tractors, loaders, cable cranes, harvesters and logging trucks.

There are major differences between segments of the forestry workforce with respect to the form of employment, which have a direct bearing on their exposure to safety and health hazards. The share of forest workers directly employed by the forest owner or industry has been declining even in those countries where it used to be the rule. More and more work is done through contractors (i.e., relatively small, geographically mobile service firms employed for a particular job). The contractors may be owner-operators (i.e., single-person firms or family businesses) or they have a number of employees. Both the contractors and their employees often have very unstable employment. Under pressure to cut costs in a very competitive market, contractors sometimes resort to illegal practices such as moonlighting and hiring undeclared immigrants. While the move to contracting has in many cases helped to cut costs, to advance mechanization and specialization as well as to adjust the workforce to changing demands, some traditional ailments of the profession have been aggravated through the increased reliance on contract labour. These include accident rates and health complaints, both of which tend to be more frequent among contract labour.

Contract labour has also contributed to further increasing the high rate of turnover in the forestry workforce. Some countries report rates of almost 50% per year for those changing employers and more than 10% per year leaving the forestry sector altogether. This aggravates the skill problem already looming large among much of the forestry workforce. Most skill acquisition is still by experience, usually meaning trial and error. Lack of structured training, and short periods of experience due to high turnover or seasonal work, are major contributing factors to the significant safety and health problems facing the forestry sector (see the article “Skills and training” [FOR15AE] in this chapter).

The dominant wage system in forestry by far continues to be piece-rates (i.e., remuneration solely based on output). Piece-rates tend to lead to a rapid pace of work and are widely believed to increase the number of accidents. There is, however, no scientific evidence to back this contention. One undisputed side effect is that earnings fall once workers have reached a certain age because their physical abilities decline. In countries where mechanization plays a major role, time-based wages have been on the increase, because the work rhythm is largely determined by the machine. Various bonus wage systems are also in use.

Forestry wages are generally well below the industrial average in the same country. Workers, the self-employed and contractors often try to compensate by working 50 or even 60 hours per week. Such situations increase strain on the body and the risk of accidents because of fatigue.

Organized labour and trade unions are rather rare in the forestry sector. The traditional problems of organizing geographically dispersed, mobile, sometimes seasonal workers have been compounded by the fragmentation of the workforce into small contractor firms. At the same time, the number of workers in categories that are typically unionized, such as those directly employed in larger forest enterprises, is falling steadily. Labour inspectorates attempting to cover the forestry sector are faced with problems similar in nature to those of trade union organizers. As a result there is very little inspection in most countries. In the absence of institutions whose mission is to protect worker rights, forest workers often have little knowledge of their rights, including those laid down in existing safety and health regulations, and experience great difficulties in exercising such rights.

Health and Safety Problems

The popular notion in many countries is that forestry work is a 3-D job: dirty, difficult and dangerous. A host of natural, technical and organizational factors contribute to that reputation. Forestry work has to be done outdoors. Workers are thus exposed to the extremes of weather: heat, cold, snow, rain and ultraviolet (UV) radiation. Work even often proceeds in bad weather and, in mechanized operations, it increasingly continues at night. Workers are exposed to natural hazards such as broken terrain or mud, dense vegetation and a series of biological agents.

Worksites tend to be remote, with poor communication and difficulties in rescue and evacuation. Life in camps with extended periods of isolation from family and friends is still common in many countries.

The difficulties are compounded by the nature of the work—trees may fall unpredictably, dangerous tools are used and often there is a heavy physical workload. Other factors like work organization, employment patterns and training also play a significant role in increasing or reducing hazards associated with forestry work. In most countries the net result of the above influences are very high accident risks and serious health problems.

Fatalities in Forest Work

In most countries forest work is one of the most dangerous occupations, with great human and financial losses. In the United States accident insurance costs amount to 40% of payroll.

A cautious interpretation of the available evidence suggests that accident trends are more often upward than downward. Encouragingly, there are countries that have a long-standing record in bringing down accident frequencies (e.g., Sweden and Finland). Switzerland represents the more common situation of increasing, or at best stagnating, accident rates. The scarce data available for developing countries indicate little improvement and usually excessively high accident levels. A study of safety in pulpwood logging in plantation forests in Nigeria, for example, found that on average a worker had 2 accidents per year. Between 1 in 4 and 1 in 10 workers suffered a serious accident in a given year (Udo 1987).

A closer inspection of accidents reveals that harvesting is far more hazardous than other forest operations (ILO 1991). Within forest harvesting, tree felling and cross-cutting are the jobs with the most accidents, particularly serious or fatal ones. In some countries, such as in the Mediterranean area, firefighting can also be a major cause of fatalities, claiming up to 13 lives a year in Spain in some years (Rodero 1987). Road transport can also account for a large share of serious accidents, particularly in tropical countries.

The chain-saw is clearly the single most dangerous tool in forestry, and the chain-saw operator the most exposed worker. The situation depicted in figure 4 for a territory of Malaysia is found with minor variations in most other countries as well. In spite of increasing mechanization, the chain-saw is likely to remain the key problem in industrialized countries. In developing countries, its use can be expected to expand as plantations account for an increasing share of the wood harvest.

Figure 4.  Distribution of logging fatalities among jobs, Malaysia (Sarawak), 1989.

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Virtually all parts of the body can be injured in forest work, but there tends to be a concentration of injuries to the legs, feet, back and hands, in roughly that order. Cuts and open wounds are the most common type of injury in chain-saw work while bruises dominate in skidding, but there are also fractures and dislocations.

Two situations under which the already high risk of serious accidents in forest harvesting multiplies severalfold are “hung-up” trees and wind-blown timber. Windblow tends to produce timber under tension, which requires specially adapted cutting techniques (for guidance see FAO/ECE/ILO 1996a; FAO/ILO 1980; and ILO 1998). Hung-up trees are those that have been severed from the stump but did not fall to the ground because the crown became entangled with other trees. Hung-up trees are extremely dangerous and referred to as “widow-makers” in some countries, because of the high number of fatalities they cause. Aid tools, such as turning hooks and winches, are required to bring such trees down safely. In no case should it be permitted that other trees be felled onto a hung-up one in the hope of bringing it down. This practice, known as “driving” in some countries, is extremely hazardous.

Accident risks vary not only with technology and exposure due to the job, but with other factors as well. In almost all cases for which data are available, there is a very significant difference between segments of the workforce. Full-time, professional forest workers directly employed by a forest enterprise are far less affected than farmers, self-employed or contract labour. In Austria, farmers seasonally engaged in logging suffer twice as many accidents per million cubic metres harvested as professional workers (Sozialversicherung der Bauern 1990), in Sweden, even four times as many. In Switzerland, workers employed in public forests have only half as many accidents as those employed by contractors, particularly where workers are hired only seasonally and in the case of migrant labour (Wettmann 1992).

The increasing mechanization of tree harvesting has had very positive consequences for work safety. Machine operators are well protected in guarded cabins, and accident risks have dropped very significantly. Machine operators experience less than 15% of the accidents of chain-saw operators to harvest the same amount of timber. In Sweden operators have one-quarter of the accidents of professional chain-saw operators.

Growing Occupational Disease Problems

The reverse side of the mechanization coin is an emerging problem of neck and shoulder strain injuries among machine operators. These can be as incapacitating as serious accidents.

The above problems add to the traditional health complaints of chain-saw operators—namely, back injuries and hearing loss. Back pain due to physically heavy work and unfavourable working postures is very common among chain-saw operators and workers doing manual loading of logs. There is a high incidence of premature loss of working capacity and of early retirement among forest workers as a result. A traditional ailment of chain-saw operators that has largely been overcome in recent years through improved saw design is vibration-induced “white finger” disease.

The physical, chemical and biological hazards causing health problems in forestry are discussed in the following articles of this chapter.

Special Risks for Women

Safety risks are by and large the same for men and women in forestry. Women are often involved in planting and tending work, including the application of pesticides. However, women who have smaller body size, lung volume, heart and muscles may have a work capacity on average that is about one-third lower than that of men. Correspondingly, legislation in many countries limits the weight to be lifted and carried by women to about 20 kg (ILO 1988), although such sex-based differences in exposure limits are illegal in many countries. These limits are often exceeded by women working in forestry. Studies in British Columbia, where separate standards do not apply, among planting workers showed full loads of plants carried by men and women to average 30.5 kg, often in steep terrain with heavy ground cover (Smith 1987).

Excessive loads are also common in many developing countries where women work as fuelwood carriers. A survey in Addis Ababa, Ethiopia, for example, found that an estimated 10,000 women and children eke out a livelihood from hauling fuelwood into town on their backs (see figure 5 ). The average bundle weighs 30 kg and is carried over a distance of 10 km. The work is highly debilitating and results in numerous serious health complaints, including frequent miscarriages (Haile 1991).

Figure 5.  Woman fuelwood carrier, Addis Ababa, Ethiopia.

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The relationship between the specific working conditions in forestry, workforce characteristics, form of employment, training and other similar factors and safety and health in the sector has been a recurrent theme of this introductory article. In forestry, even more than in other sectors, safety and health cannot be analysed, let alone promoted, in isolation. This theme will also be the leitmotiv for the remainder of the chapter.

 

 

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Contents

Forestry References

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