Brazil has always been a country with a powerful agribusiness sector, especially in the forest area. In recent years, much has changed in relation to awareness-raising, adoption of public policies and the new practices that foster a more sustainable forest management.
In the management of renewable forests, the first stage to be considered is the selection of the most suitable species and genetic material for each region, according to the production objective and the specificities of climate, soil and relief, since obtaining a higher productive return depends on the choice of the species. After the definition of the species begin the processes of seedlings production, soil preparation, planting, forest maintenance until the harvesting, which marks the end of the cycle of a sustainable forest planting, thus allowing another cycle to get started on the same ground.
Since the 1990s, with the opening of the market for imports and the entry of foreign companies in Brazil, there has been a significant increase in investments in mechanization of harvesting processes, which has led to a strong growth in this sector.
Large forestry companies around the world are now using large machines with high capacity in their operations. In this regard, the high investments in mechanization, made it necessary to use management tools that help companies to make the best possible use of these resources.
In the mechanized harvesting process, factors such as terrain declivity are considered a major problem for the operation due to the risk involved in using these machines on very winding terrain. Another important issue is how to extract the felled wood from the hillsides. Harvesting in such areas imposes challenges not only with regard to the machinery to be used in the operation, but also in the harvesting planning for these areas with strategies for the transport of the harvested wood.
In many regions in Brazil, the planting of renewable forests is done in predominantly flat areas, facilitating the whole process of planting, harvesting and transport, reducing risks, costs and increasing the operation productivity. However, both in Brazil and in other countries, it is also necessary to make plantations in hilly areas.
Growth cycle of the forest species
Another relevant factor which can influence the harvest planning is the timespan of the forest growth cycle. The large forest-based companies in Brazil have eucalyptus plantations, a species that, thanks to climate, soil and other factors, finds favorable conditions. The growth cycle takes thus 6 to 7 years on average. Another species − the pinus − is more adapted to colder climates and has a slightly larger cycle. Of course, the cycle depends on several factors, including the purpose of the use of the timber. When the timber is to be used for industrial processes, e.g., cellulose industries, MDF manufacture or even carbonization for power generation, there is no need for thick logs, which enables the cycle reduction. In turn, when the purpose of the timber is for milling, regardless of the species, there is of course a need for a longer cycle so that the trees have time to grow.
In Portugal, however, even with the planting of eucalyptus, the average cycle is 12 years, which is almost twice as much as the Brazilian average, which is mainly due to climatic factors. In Chile, which has a rigorous winter, there is a strong timber market with focus on pine trees and the cycle can reach up to 24 years. Within all this time, what is being harvested today was planted under very different planning conditions and technologies.
In this regard, the time factor becomes very relevant, because elements such as road planning according to the adopted harvest technology are critical for the coming harvest. How to plan and build roads also takes time, therefore, companies need to anticipate their concerns about harvesting, preparing themselves up to three years before starting the operation. This period is necessary to carry out the most optimized road construction planning. Factors such as the release of permits, compliance with legal and environmental requirements and the preparation of the area where the timber will be kept for later transport will also require a lot of attention.
When the areas are predominantly flat, the roadside itself becomes a place for keeping the timber (Figure 1).
However, building large roads enough to support the timber in high declivity terrains becomes very expensive, and it is necessary to plan timber depots (Figure 2).
In this image it is possible to observe a set of roads and some points that represent these depots. The depots are usually planned considering: the best location, in order to optimize the construction cost (of the depot and road) and also the range of the harvesting machines. Also commonly used are tower yarders with cables to collect fallen trees in sloping areas. In these areas with the longest harvest cycle, it is common to take advantage of the road constructed areas for post-harvest planting.
The planning of the next cycle is carried out only after 24 years, taking into account the conditions and harvesting equipment by that time.
In the face of all these challenges, harvest planning managers use reliable information management tools to solve complex problems and support their decisions.
In the United States, for instance, there are other challenges, as there is a great variability of tree species in the farms and, without physical boundaries such as roads, planning is carried out considering the spatial occupation. In this case, it is necessary to use more specialized tools to plan the entries and/or greater human effort to carry out the timber harvesting and transport planning.
Efficiency and productivity of machines
After overcoming the challenges of planning, companies begin to focus on achieving efficiency and productivity in the execution of the harvest itself.
Today, many technological innovations are being incorporated into machines and equipment to maximize productivity and minimize risks and costs. With the possibility of greater use of IoT (Internet of Things), companies capture data generated by the machines (the machine itself and also its heads) to evaluate the reasons for downtime, the time that the equipment is turned on or off, among other aspects. These analyses help companies identify opportunities for increased efficiency. A 30-minute efficiency increase per day per machine, depending on the number of machines and operators, can generate a cost reduction estimated at millions of reais.
There are numerous challenges that need to be overcome in the day-to-day business of forest companies in order to achieve operational excellence. Specifically in the harvesting process, it is important that managers can count on a good management system to support all stages of the activity, starting with a planning with reliable, structured and fast information to support better decision-making, and, during the execution of the harvest, with the information captured from the machines, be possible to perform the quality control of the operations and the continuous process improvement.