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Rudolf Heinrich1

1 Chief, Forest Harvesting, Trade and Marketing Branch, FAO Forestry Department, Rome, Italy.


This paper highlights briefly the main issues by which world forestry is challenged, and refers to the importance of appropriate road harvesting operations with particular reference to mountainous forests in the context of sustainable development. The importance of recognizing a wider range of forest products, both wood and non-wood, as well as the service functions of forests is emphasized as a prerequisite for sustainable forestry. An analysis is provided of the different levels of mechanization that can be recognized, considering some of the more recent developments in forest operations. A section on environmentally friendly forest road planning and construction refers to new surveying and construction methods, and draws attention to the importance of appropriate drainage facilities and road protection engineering works as well as adequate road maintenance. Emphasis is placed on different modes of transport in steep terrain, especially low impact systems such as tracked skidders and cable logging systems, referring to recent innovations such as the use of mobile cable systems in combination with wood processors and the research efforts going on, searching for solutions to introduce fully mechanized wood harvesting operations in steep terrain. Special mention is made of the utilization of building cranes where special silvicultural prescription have to be applied safeguarding advanced forest regeneration and extracting single tree stems in selective cuts from old-growth forests. Aerial systems such as helicopters, balloons and cyclocraft are also discussed briefly. Finally, recent FAO initiatives aimed at promoting environmentally sound forest harvesting practices worldwide are described.


World forestry is challenged by a number of issues such as the loss of the earth's biodiversity, forest decline because of air pollution and transformation of old growth forests in the temperate region, decrease of forest land due to conversion to other land uses in tropical countries, forest land degradation and tree stand impoverishment as well as generation of forest waste caused by inappropriate and unsustainable forest harvesting practices. Recently issues such as labelling of wood products, suggestions for trade restrictions and even boycotts of tropical timber from non-sustainably managed forests have emerged as further causes of concern in forest and wood products development.

Although great advances have been made during the last two decades in developing and introducing highly mechanized and specialized machinery in forest operations, which permits environmentally sound, economically profitable and socially acceptable forest uses to support sustainable forest development, there still is a great need to ensure the introduction and application of appropriate policies and practical codes of environmentally friendly harvesting practices with the aim to advance sustainability of both timber and non-timber forest products.

Worldwide in 1991, some 3.4 billion m3 of roundwood (FAO 1993) have been removed from the world's forests of which a little bit less than half has been used for industrial purposes and the other half as fuelwood. The presently existing forest resources worldwide are estimated to amount to about 3.4 billion ha. With an ever-increasing rate of deforestation for other land uses (conversion to agricultural land, infrastructure, and urbanization; presently the rate of forest decrease in the tropics alone amounts to some 15.4 million ha/a), it is evident that a concerted effort is needed to motivate policy-makers, managers, technicians and forest operators to encourage forest development programmes that harmonize interests in conserving forests as well as to wisely use the potential of the forest while maintaining its full regeneration capacity.

Harvesting and sustainable development

At the United Nations Conference on Environment and Development (UNCED) held in 1999 in Rio de Janeiro, forestry received major attention under Agenda 21, Chapter 11 entitled "Combating Deforestation". With respect to forest use, particular reference was made to the need to promote efficient utilization and assessment to recover the full valuation of goods and services provided by forest lands and woodlands (UNCED 1992). As a matter of fact in many forest operations, we can recognize that the full potential of forests and forest lands is far from being realized as a major source for development.

A prerequisite for sustainable forest utilization is comprehensive pro-harvest planning, appropriate monitoring and execution of operations as well post-harvest evaluations, increasing the production of goods and services, particularly in broadening diversity of yield of forest use, covering timber and non-timber forest products. This should help to generate more income and employment, particularly enhancing life of rural populations, without compromising the regenerative capacity of the forests and their continued contribution to human welfare, satisfying the aspirations of goods and services for future generations.

There are numerous definitions of sustainability. In 1904, G.L. Hartig, Head of the Prussian Forest Administration in Berlin, defined sustainability as follows:

Every wise forest director has to have evaluated the forest stands to utilize them to the greatest possible extent, but still in a way that future generations will have at least as much benefit as the living generation.

On the subject of sustainable development, in 1988 the FAO Council adopted the following definition:

The management and conservation of the natural resource base and the orientation of technological and institutional change in such a manner as to ensure the attainment and continued satisfaction of human needs for present and future generations. Such sustainable development conserves land, water, plant and animal genetic resources and is environmentally non-degrading, technically appropriate, economically viable and socially acceptable.

Perhaps the most, widely quoted definition of sustainable development is that of the Brundtland Commission (WCED 1987): Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

In view of the dwindling resources due to forest decline in the temperate zone, conversion to other land uses and degradation in the tropical areas, it is essential that forest harvesting practices are carried out in a manner to guarantee the sustainability of the forest resource base.

It is well recognized that the complexity and diversity of the vegetative cover as well as the fauna of the various forests require well-planned and controlled forest operations and interventions to make full use of the potential of wood and non-wood forest products, compatible with environmental conservation. In some instances, however, the optimum use of all forest products may not be feasible due to various factors which include, amongst others, environment, accessibility, availability of harvesting technology, resources, laws and regulations.

The new dimension of harvesting

FAO's perception of forest harvesting in relation to socio-economic development has gone through a substantial evolution. In forestry, a concept which needs to be more frequently introduced is the use of a wider range of forest products based on sustainable resource management. In addition to timber, a multitude of non-wood products are available from the forests which can be most beneficial in terms of employment and income generation, particularly for the local population. In many instances, harvesting therefore is no longer synonymous of logging as it deals with a wide array of non-wood outputs (de la Cruz 1989). A partial list of such products may include plants for ornamental and medicinal use, honey, resins, tannin, fruits, mushrooms, nuts, wildlife for food and hunting trophies. Harvesting therefore may be defined as the procurement of raw materials from the forests. When recognizing this new approach, harvesting as an independent technical discipline has to be seen as an integrating function forming a strong link between the resources, forest-based enterprises and markets. FAO, besides its traditional work in wood harvesting, has recently developed an action programme on harvesting of non-wood forest products and has undertaken case studies on small-scale harvesting with strong people's participation, published as FAO Forestry Paper No. 87 (de la Cruz 1989), as well as a study on the collection, processing and marketing of edible mushrooms from forest plantations in Chile (Donoso and Kilkki 1993). By 1990 the value of these mushrooms had reached about US$ 3 million annually.

Mechanization in wood harvesting operations

A key element for the success in introducing environmentally sound forest operations is the proper planning, control and evaluation of harvesting operations particularly in steep terrain. This is not only important to reduce the environmental impact of such operations but also to reduce costs and improve productivity and maximize the value of forest products utilized on a sustainable basis. In recent years, great advances have been made to increase productivity particularly in the industrialized countries where the slogan is used that during forest operations, the forest worker never will touch the forest ground with his feet because the whole operation is mechanized. In relation to the different levels of mechanization, one could classify the harvesting methods as follows:

Manual wood harvesting operations

This is the most basic harvesting technique that exists. Trees are felled by hand or powersaws, delimbed and crosscut and extracted manually, often by gravity on steep terrain. Many types of pushing, pulling and rolling operations have been developed and existed for many years.

Nowadays they only can be found in very remote areas and particularly at the local level in non-industrialized operations.

Low-level mechanization

Felling, delimbing and bucking carried out manually, wood extraction and transport by means of animals.

Medium-level mechanization

Felling, delimbing, bucking by chainsaws. wood extraction and transport by specialized machines, such as agricultural tractors with forestry attachments, skidders. crawler tractors, cable systems; winch lorries and timber trucks.

High-level mechanization

Felling by chainsaws, all other work such as wood extraction, delimbing. crosscutting and debarking is carried out by machines.

Complete mechanization

All operations from felling to hauling are carried out by machines in easy-to-moderate terrain. Often a combination of wood harvesters and forwarders is used. These systems have so far not been introduced in steep terrain, except on a trial basis, utilizing a special timber harvester, which is able to manoeuvre in mountainous terrain.

A further complication in wood harvesting in steep terrain is the often very specific silvicultural prescriptions, in some cases even restricting substantially cutting permits. In a number of countries, clearcutting is not permitted. This particularly applies to tropical natural forests where only selective cutting can be carried out, which requires carefully planned and controlled operations to limit the environmental impact. But even in temperate forests clearcuts are limited in sizes, shapes and patterns. So, for instance, in Austria clearcuts are limited to about 2 ha. In the past, essentially longitudinal strip cuts were practised; nowadays felling patterns no longer have only rectangular forms but take into consideration terrain pattern.

Environmentally friendly forest road planning and construction

In many forest and terrain conditions, the forest road network is a prerequisite to introduce sustainable forest practices. Yet if not carefully planned, constructed and maintained, forest roads can be a major source of soil erosion. For instance it has been reported that an estimated 90 percent or more of soil erosion resulting from timber harvesting in the tropics is directly attributable to roads (FAO 1977). Road locations therefore must be properly planned in advance in order to restrict roadside clearing, to minimize the amount of earthwork required when preparing the road running surface and landings and when excavating the cut and till slopes, and to maintain the road length per area unit to an absolute minimum.

Nowadays efficient road surveying techniques by means of hand held instruments such as clinometer, compass, altimeter and measuring tape. provide sufficiently accurate, fast and economic results. An experienced forest engineer may survey and locate 1 km of forest road in 5-12 working hours depending on forest and terrain conditions.

New construction techniques such as the use of hydraulic excavators have permitted the construction of environmentally acceptable roads, even in steep terrain.

Construction costs as compared with the traditional methods, using bulldozers or traxcavators, are only slightly higher.

The density of a road net system is expressed in m/ha or road length per m3 of roundwood removed per year (m/m3/a). Road net density in natural forests in the tropics tends to be generally low, often some 7-10 m/ha, whereas under intensive forest management in plantation forests in temperate regions 20-40 m/ha is not uncommon.

Table 1. Suggested road standards on hilly to steep terrain.

Road type

Road width

Maximum gradient, %

Minimum gradient

Estimated cost


Transport direction

Adverse direction

Main forest road






Secondary forest road


10 (12)1




Skid road


15 (20)1




Maximum gradient for short distances only

Table 1 provides some suggestions for possible road standards in hilly to steep terrain for single-lane roads with lay abouts, limiting soil movements during construction time and future erosional hazards.

With reference to production rates and costs for earth movements by angledozers or traxcavators for a 4.5 m road width in easy to difficult terrain in temperate forests, Table 2 provides some data based on field experience over a number of years (Sedlak 1985).

Table 2. Production and cost estimates for a 4.5 m wide forest road in temperate forests


Terrain condition




Average slope, %




Road formation productivity, m/h




Cost per running m in US$




Drainage facilities

In many instances poor drainage facilities of forest roads are a major source of erosion caused by excessive water or moisture. The drainage system must allow to drain off efficiently surface and subsurface water, taking into consideration natural drainage patterns. Properly designed mountain roads generally are provided with mountain side road ditches, culverts with protected inlets and outlets and, if required, with fords and bridges. To drain off road surface water earth cross drains as well as open top culverts at appropriate spacing and with a cross gradient of 6-7 percent are placed in the road.

In many countries, various types of open top culverts have been developed and introduced, made of locally available material which could be small-sized logs, combination of logs and timber or timber only.

Road protection engineering works

In stabilizing slopes and gullies a combination of structural mechanical engineering works and revegetation measures will be most effective. Various designs of retaining structures such as gabions, stone walls, log or precast concrete crib revetments, reinforced earth works, etc., are in use in numerous countries.

For low-cost roads, building material must be selected close to the construction site. Inexpensive structures such as gabions which can be easily set up with proper supervision by unskilled labourers have proved to be effective and to integrate well in the environment. From various observations made, it was noted that two man-days were required to construct one m3 of gabion.

The work comprised preparation of wire mesh, collection of stones near the construction site, transport and setting up the stones as well as rock fills. To protect slopes from surface erosion, seeding and many times also planting of brush layers, are applied. A technique often used is called contour wattling which essentially consists of driving stakes into the soil and placing cuttings or rooted plants into contour ditches. When applying contour wattling with a vertical spacing of 1.5 m, and putting in stakes at 50 cm intervals, as well as putting in bundles of cuttings with a diameter of 15 cm and 3 m length, a ten-man crew can carry out rehabilitation work on an area of about 250 m2 per day.

Road maintenance

Road maintenance is required to permit efficient and safe use of the road and prevent a negative impact on the environment. Regular maintenance schedules should foresee inspections of road structures, drainage facilities and conditions of road surface.

In general yearly road maintenance costs can amount to 3-5 percent of the construction costs; however, under extreme terrain and weather conditions it may be higher. Road maintenance costs can be kept minimal on roads properly designed and located (3% minimum and 9 % maximum gradient), as well as closing off roads during heavy rain periods. For road maintenance manual workers can be ideally employed.

Wood transport in steep terrain

A multitude of wood extraction systems have been developed to transport wood from the felling area to the roadside, landing or river. Essentially they can be categorized in manual, gravity, ground dependent, cable, balloon and helicopter logging systems.

Wood transport by gravity

In mountainous forests traditional systems have evolved, using gravity to move logs downhill by means of hookeroons on the ground or by employing log chutes, flumes or wires. Due to erosional hazards gravity logging should be limited to 200-300 m distances and preferably be replaced by other transport means such as cable logging systems.

One innovative method in gravity logging is the use of the polyethylene chute (FAO 1989) as a substitute for traditional log or timber chutes. Short poles, posts and small-sized logs with a diameter of up to 35 cm can be transported efficiently downhill in the chute with no damage to the soil or timber stand.

Low ground pressure skidders

The negative effects of ground skidding operations such as compaction of forest soils by the machine, danger of soil erosion when rutting occurs, particularly on steep slopes, damage to forest regeneration and the remaining trees in selective cuts can only be overcame if a proper skid trail system is developed prior to wood extraction and the skidding machines are restricted to these trails. It is worth noting that the use of skidders equipped with high flotation tyres has considerably reduced soil compaction as compared with the conventional skidders and agricultural tractors used in wood harvesting.

Under tropical forestry conditions, the low ground pressure tracked skidder has gained acceptance (Buenaflor and Heinrich, 1980). This machine is particularly suitable for steep terrain and wet soil, its ground pressure is half and the speed is twice that of a conventional crawler tractor. It extends the harvesting opportunities on slopes of up to 50 percent. Although machine availability is somewhat lower than for the crawler tractors due to more maintenance work for the flexible tracks, the overall performance and productivity of the tracked skidder is higher than that of the conventional crawler tractor. A further feature of the machine is that part of the log rests on the deck of the tracked skidder and therefore ground disturbance by the pulled log is reduced.

Cable harvesting equipment

In a number of developing countries, particularly in plantation forests in the tropics, traditional long-distance and mobile cable systems have been introduced recently. In industrialized countries, due to high-level salaries and intensive forest road development, nowadays only mobile cable systems are in operation.

Traditional long distance gravity cable systems

For many developing countries mobile cable systems are still far too advanced for socio-economic reasons due to lack of trained manpower and low road net density to employ efficiently the advanced cable logging technology in combination with processors. Where labour is easily available and labour costs are moderate, one should aim to employ people to a maximum extent.

The simplest of all the traditional cable logging systems is the gravity skyline system which for cost and labour intensity reasons has been mostly substituted in industrialized countries by advanced mobile cable systems. In developing countries however, where more and more plantation forests in hilly terrain reach the age for harvesting, this system can be employed as an environmentally friendly technology, keeping the impact of wood harvesting on the forest stand, soil and terrain to an absolute minimum.

Gravity cable systems are composed of a single drum, a skyline, a mainline and a carriage with or without built-in stopping device.

The setting up of such a system requires a detailed survey of the skyline corridor and the selection of appropriate intermediate support trees, which are required for a multi-span cable logging system.

Generally, these systems have spans of 1000 to 1500 m and logs can be dragged up to 50 m from both sides of the skyline. For instance, in Bhutan and Pakistan, when using a single drum yarder of 50 kW and a 25 mm skyline with a cable length of 1000 m and a carrying capacity of 2.5 tons, a daily productivity of 20 to 25 m3 has been reported. Recently, such systems have been introduced in plantation forests in Chile and in natural forests in Indonesia, Malaysia and Philippines.

The system can be used to pick up logs at any point along the skyline, but it can also be a means of linear transport, substituting partly a road net system. The latter case was successfully introduced in the Himalayas in Pakistan to overcome extremely difficult terrain in order to transport wood from a high plateau. Because of the manual rigging of the support trees, the setting up time of a cable installation generally takes two weeks.

The minimum wood volume required is a critical issue which has to be worked out on a case-by-case basis in order to determine the economic feasibility of the project.

In a number of countries FAO has encouraged studies and application of skyline systems which will permit environmentally sound forest harvesting practices in mountain forest management.

Mobile cable systems

Generally such cable units are mounted on a vehicle which can be a trailer or a self-propelled carrier. In addition they are equipped with a folding or telescopic extendable tower which serves as an endmast. Generally such cable systems can cover a distance of up to 500 m. Logs can be pulled in from both of the sides of the skyline up to a distance of 50 m, which means that one cable setting can cover a maximum area of 5 ha for harvesting timber. In comparison to the traditional cable system, setting up and dismantling time is relatively short. For instance the time of setting up the equipment could take half a day to two days depending on the size of the mobile cable unit (small, medium, large), the terrain and the forest conditions, as well as the skills of the cable crane operators.

Many types of small and medium size mobile tower cable systems are available in Europe, whereas the bigger ones are used traditionally in the United States. With small and medium-sized cable equipment, the transport productivity could range from 4 to 10 m3 per machine working hour.

Use of mobile cable systems in combination with wood processors

Recent developments led to the introduction of cable systems operated by remote distance control which significantly improved the safety aspects of the operators involved in cable logging activities. Often cable units are now employed in combination with wood processors located at the landing of the cable unit. In such a case the entire operation is mechanized except for felling the tree by chainsaw in the terrain. After felling the tree by chainsaw, the full tree is transported by the cable unit to the roadside, where delimbing and processing into the desired assortments takes place. Wood felled the same day or one or two days earlier can be transported to the end user in very fresh conditions. Availability of raw material can be very well planned and, due to the speed of the operations, absolutely no quality loss of the wood is experienced.

The newest development in cable logging is the remote controlled cable system "woodliner" produced by Konrad Forest Technique Austria, which can be used for uphill and down hill transport. The cable unit consists of a skyline with 18-20 mm. of a mainline of 8-12 mm with a length 50-70 m, a carriage powered by a diesel motor with 21 kW, permitting a carrying capacity 1.4 to 1.7 tons. Advantages of this system include its rapid setting up and dismantling time because of using a skyline only. Work safety and operating efficiency are improved due to remote controls. Movements of the carriage and the winch of the mainline are hydraulically operated

This cable system can most effectively work together with a wood processor produced by the same firm called "Woody 50" which has the specifications summarized in Table 3.

Table 3. Specifications for the processor head

Max. bucking diameter, cm


Delimbing diameter, cm


Feeding speed, m/s


Chain speed, m/s


Working pressure, bar


Production costs per m3 of wood harvested and transported to the road when using a combination of cable systems and processors in steep terrain tend to be twice as much than when harvesters and forwarders are used in moderately hilly terrain. This difference in production costs is caused mainly by manual felling of the trees and the generally somewhat lower production rates of cable systems as compared with ground machines. Costs per m3 of harvested wood tend to range from US$ 25 to US$ 60 delivered at the forest road.

Use of construction cranes

In many industrialized countries, construction cranes do exist in abundance for the housebuilding sector to carry a variety of lifting jobs. FAO has recently learned of a forest enterprise in Austria using a building crane for the purpose to harvest trees in one hundred year old timber stands while at the same time protecting emerging regeneration. FAO has commissioned a study to document the possible use of construction cranes in forestry. From the study it emerged that when lifting trees with maximum permissible log length which can be managed by the crane, production rate per machine hour amounted to about 12.5 m3, for the whole tree method to about 15 m3 per machine hour, average load size of 1.2 m3 over an average distance of 30 m. The maximum distance to transport logs to the roadside by construction crane is 45 m. The standing wood volume varied from 800 to 1000 m3/ha. Some 180 m3 of logs have been extracted from two study sites. The costs for the logging operations for lifting the logs ranged from US$ 8.50 to US$ 11.20.

Helicopter logging

Helicopter logging is an option for harvesting in forests with most valuable frees which for environmental protection or due to the remoteness of the area do not have any infrastructure in terms of forest roads and/or skid trails. It has been also proposed in a number of instances where typhoons or hurricanes have devastated forests with plenty of trees damaged, broken and knocked down. Helicopter logging is utilized most widely in the United States. In recent years, some 2-5 million m3 have been harvested per year. Using the Sikorsky S61, an average production of 350 m3 of logs in a six flight/hour/day could be expected. Helicopter use for wood harvesting in other industrialized countries is rather restricted and mostly limited to emergency or very special cases. However, some helicopter logging operations have been introduced recently in developing countries. The World Bank has reported on a helicopter logging operation in a 38 000 ha timber concession in Papua New Guinea. And FAO has recently provided technical advice for a helicopter salvage operation in typhoon damaged forests of Western Samoa (Dykstra 1994). A draft deed of licence for low-impact helicopter salvage logging including operational plans has been prepared for the Government of Western Samoa. In the planned helicopter operation, a New Zealand based company was going to undertake the operation by using heavy duty lift helicopters The rated lifting capacity of this model is 5 tons, withan average fuel consumption of about 1000 litres per flight hour of Russian origin, model Kamov KA 32.

In Sarawak a private US/Australian firm has been undertaking successfully harvesting operations in natural forests for the past two years.

Balloon and cyclocraft

A few balloon systems have been rating in the United States. Presently, to our knowledge, still one balloon is being utilized to support a cable logging operation so that it is not necessary to rig intermediate support frees. Strong winds can be a problem; in fact one balloon has been destroyed by a storm.

Research is going on the cyclocraft which seem to be a futuristic possibility of carrying out airborne wood harvesting operations. A research based in the United States assessed costs for a cyclocraft compared with a MI 26 helicopter. According to their analysis leasing a cyclocraft would turn out to cost US$ 2500 per hour whereas the lease of a helicopter would amount to US$ 17 500 per flight hour.

Walking harvester

A walking harvester designed by Plustech Oy in Tampere, Finland, is the first working machine application of walking technology in the world. In the forest, the six-legged machine proceeds at a leisurely pace and it can operate in extremely difficult terrain. The walking machine not only moves forward and backward, but also sideways and diagonally. In addition, the machine can turn right from where it stands. Owing to the new moving directions the operator can always choose the shortest way to the next target. The result is a reduced need for motion, particularly when compared to the movements of wheeled or caterpillar-driven machines performing corresponding tasks. The terrain dictates whether the machine uses three, four, or five legs for moving. The walking machine steps over obstacles and adapts itself to an irregular forest floor, instead of attempting to clear the ground. Moreover, the operator can adjust the ground clearance of the machine between 20 and 120 cm. As a result of the spot-like ground contact, soil compaction is minimized and no continuous tracks are left behind a walking harvester, which is the opposite of what conventional machines do.

Conclusions and recommendations

Great advances have been made in harvesting technology which permits forest harvesters to carry out forest operations more safely and with reduced physical stress, increased productivity and a considerable reduction of the environmental impact on the forest stand. In easy to hilly terrain in many forest enterprises a high degree of mechanization has been reached, in a number of cases even achieving full mechanization using a combination of harvesters and forwarders.

In steep terrain in industrialized countries, a high level of mechanization can be recognized when using advanced remote controlled mobile cable logging systems in combination with processors. A new development has taken place in the design of a self-propelled carriage, which could reduce substantially setting up and dismantling costs as only the skyline has to be installed.

In many developing countries more and more forest plantations reach the age where silvicultural improvement or final harvesting operations are required, introducing intermediate mechanized harvesting systems. As many of these plantations have been established on marginal soils and in steep terrain, often the only available land for forest purposes, there is a great need to test environmentally acceptable harvesting systems, which can also be justified from a socio-economic point of view.

There is a great need for the dissemination of information on appropriate harvesting technology and there is a lack of practical oriented field manuals. Attention should be drawn to enhance manpower training for harvesting planners, technicians and foremen. In a logging training survey carried out by FAO, it became evident that training of forest operators was neglected as compared to training at the management and technical level (FAO 1989).

FAO forest harvesting initiatives

The FAO Forest Harvesting Bulletin

FAO has recently established a biannual newsletter with the aim of creating a global forest harvesting network to facilitate the dissemination of information and experience in order to promote environmentally sound forest practices worldwide. At present all Member Nations of FAO participate in the network through nearly 4000 individuals and organizations.

Programme on environmentally sound harvesting to sustain tropical forests

The purpose of this programme is to contribute to sustainable development by developing, testing and assisting to implement improved technologies for harvesting of both industrial timber and also non-wood forest products from tropical forests. A major emphasis of the programme at present is on the development of a "model" code of forest practices which will be designed to assist forest enterprises and government agencies in reducing environmental impacts associated with harvesting operations while at the same time improving the economics of forest operations.

Equipment information database

The FAO Forest Harvesting, Trade and Marketing Branch has established a computerized database on forest engineering, harvesting and transport machinery, equipment and tools which presently covers more than 240 manufacturers worldwide. Based on various field studies, data on productivity and costs of a wide range of different harvesting systems have been collected which permit rapid evaluation of costs and production.


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