The Department of Environmental Affairs, in partnership

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1 Invasive tree species cleared for Eco Furniture Project s school desk production This is a three part article that continues on pages 37 and 52. The four chainsaw operators who received training in specialised tree felling techniques The Department of Environmental Affairs, in partnership with the Department of Basic Education, has launched a project to address the shortage of school desks in South Africa. The Eco Furniture Project, which is implemented through the South African National Parks agency (SANParks), will use invasive tree species in the production of quality school desks. These desks will be supplied to schools throughout the country and about 160 jobs are expected to be created at each of the 18 factories to be established. Ancillary products such as affordable coffins and furniture will also be produced. Harvesting This mammoth project starts with the harvesting of invasive tree species across South Africa. SANParks manager for biodiversity social projects Olga Jacobs explains that invasive species such as Poplar, Eucalyptus, Pine and a very small amount of Blackwood is harvested in locations near established factories to supply the project. In future, the harvesting operations can move further away from the factory facilities as planning for long-term transport solutions is underway. One of SANParks general responsibilities is to ensure future plant biodiversity. By removing invasive species we are increasing biological diversity, preserving precious water resources and opening up land for productive use. At the same time we are supplying a steady stream of raw material to the furniture factories. Jacobs says the trees are harvested on municipal and private land. The largest portion of the harvesting is done on municipal land where procedures for the removal of these species are already in place. Private land owners also often contact SANParks to remove these species from their land. Some land owners have already taken trees out and just require the logs to be removed. Other private land owners in Wood 04/ April 2014

2 uncontrolled and unmanaged in rural and urban areas. Trees are sometimes leaning to a side, multi-stemmed, large crowned and located next to buildings and structures. He adds that the harvesting of such trees requires different skills than those required for chainsaw harvesting in managed plantations where trees are planted in rows and maintained. Getting the pull (rigging) rope up the tree without climbing For Taljard the first step is to assess the learner s basic skills level and importantly to page 6 the areas of the factories could possibly be contacted to partake in this project by allowing SANParks to harvest on their land. Further, harvesting is done by five teams; one each in the regions of Graskop, Makhado, Heidelberg, Durban and Knysna where five factories have already been established. Harvesting teams consisting of four to eight people employ conventional or low-level mechanised harvesting techniques that mainly include felling and tree processing through the use of chainsaws. Jacobs notes that these operations can be dangerous and SANParks have taken great care in ensuring that the best chainsaw operator and tree felling training was provided. Chainsaw training is done by Enviro Chainsaws, a Stihl dealer from Centurion s training division. The company started the specialised tree felling techniques course in December and four operators have already received certification. The plunge-cut, where the operator bores into the centre of the directional notch to cut the core of the tree Chainsaw operator instructor Marius Taljard says the training was done over 10 days at a harvesting location and covered critical points such as risk assessment, planning, safety, specialised tree felling, delimbing, crosscutting techniques and equipment. Taljard explains that trainees need to be trained chainsaw operators with a high level of competency before being trained in specialised tree felling techniques. This is not a chainsaw operator course, the learners already have to be competent in the basic chainsaw operator skills. This course prepares the chainsaw operators for high risk and dangerous work. Eco Furniture Project chainsaw operators work in a challenging environment where trees grow The back cut should be about the same height as where the directional cut and bottom cuts meet, this offers better control April

3 From page 5 Invasive tree species cleared for Eco Furniture Project s school desk production his/her ability to maintain a saw chain. The kingpin of the whole operation is a sharp saw chain. During the course more advanced filing techniques that suit the hard working conditions are discussed and demonstrated. When Taljard knows that the operators are competent, the intensive but rewarding training starts. Planning for felling and risk assessment is the first and most important lesson learnt during the training, notes Taljard. What is left of the hinge after felling Planning for felling Site and tree risk assessment is vital to the operation. The operators learn to assess moveable and unmovable structures, they do clearing around the tree, they determine the wind direction, slope and underfoot condition, and establish well defined 45 escape routes. The tree assessment entails looking for leaning trees, dead or decaying wood, flaking bark and fungi around the stem to determine the condition of the tree. Operators also learn that those not involved with the felling of the tree need to be more than two tree lengths away from the site. The chainsaw operator must then plan the felling operation, the felling direction and what equipment to be used. The circular back cut where aluminium or metal wedges are placed into the cut at third intervals thereby keeping the cut open Bringing the tree down in a chosen direction Other aspects include teaching operators how use a simple equation called equidistant to determine the reach of the tree when it is felled. The next step is deciding on the felling equipment to be used as well as the felling cuts to be made. Equipment such as felling bars, felling wedges, throw lines, rigging ropes, pulleys, rigging karabiners, anchor slings, prussik cords and winches are designed to make the chainsaw operator s job easier and safer. Felling equipment is only an aid to good felling techniques. A great Eucalyptus Grandis seconds after felling Many operators do not know how to best use the available tools and as a result they put more strain on their bodies and equipment during felling, thereby creating unsafe practices and conditions. Part of our job at Enviro Chainsaws is to teach operators how to effectively use the equipment, explains Taljard. 6 April 2014

4 straight up and without defects. However, in unmaintained areas these systems are critical and we make sure the operators know exactly what they are doing when using these techniques. The wedges which are hammered with 3,6 kg sledge hammers He adds that the training focuses on controlling the tree with equipment and methods useful in bringing down trees that are close to each other and near buildings. These systems enable the operator to bring down the tree in a safe manner. The chainsaw operators are taught how to get a pull (rigging) rope up the tree without the need for climbing, how to set up a mid-line hitch, how to attach single or double pulleys and how to attach the pulleys to the anchor point by means of slings. These systems are not used in normal commercial forestry harvesting practices, as those trees typically grow Making the felling cut The directional cuts are very basic with slight variations depending on the size and shape of the tree and whether or not stump height is of concern. The bottom cut should angle upwards to the directional cut, this creates a wider notch that will take longer to close when the tree is on its way down reducing stress on the tree. When the felling cut is above the normal the bottom cut should angle upwards to the directional cut, this creates a wider notch and will take longer to close when the tree is on its way down reducing the chances of stress. The back cut, however, should be about the same height as where the directional cut and bottom cut meets, this offers better control. Taljard explains that there are several different techniques for making the felling cut depending on the diameter of the tree. to page Wood 04/2014 April

5 From page 7 Invasive tree species cleared for Eco Furniture Project s school desk production For instance, when a tree s diameter is twice the length of the chainsaw s guidebar, the operator bores into the centre of the directional notch to cut the core of the tree. This is called a plunge-cut. A popular felling cut is the circular back cut where aluminium or metal wedges are placed into the cut at third intervals thereby keeping the cut open. After the completion of the cut the wedges are driven in with 3,6 kg sledge hammers. The larger the tree, the more wedges are used. The wedges also keep the cut open so that the guidebar is not pinched. The hinge, which is the unsawn piece of solid timber between the directional notch and the felling cut, controls the tree when it falls. If an operator cuts through the hinge he can lose control of the tree. The mighty chain saw Incorrect hinges and thickness of hinges could also create unnecessary stress that can cause premature cracking of the timber resulting in unnecessary waste and loss of good timber. Delimbing and crosscutting Taljard further explains that once the tree is felled, the operators start to plan the debranching and removal of branches using correct debranching techniques. Removing the branches from the outside of the crown to the stem of the tree exposes the branches on which the tree is lying. These branches should only be removed when it is safe to do so. The sections are then crosscut, the box cut technique in conjunction with wedges is used to crosscut large stems reducing the chances of guidebar pinching. The cut logs are then processed on a portable sawmill which is used in-field at many of the harvesting locations. Using skills for self-employment Meanwhile Jacobs explains that the certified chainsaw operators can use their newly gained skills to pursue their own business opportunities in tree felling. The chainsaw operator is urged to look beyond just the Eco Furniture Project to better his or her life in the long-term. If our trained operators can find ways to create even more jobs through entrepreneurial initiatives then the project can snowball to be even more productive and successful. Product supply Harvesting products are purchased from several local companies and tenders were put out for the required equipment Wood 02/2014 Read the follow-on story on portable sawmilling for the Eco Furniture Project on page 37. Share your comments by ing sinette@woodsa.co.za SG 8 April 2014