Plantations
Harvesting
Photo:National Association of Forest
Industries
The first products are often harvested from plantation forests when they are thinned. This takes place at regular intervals during the life of a forest to remove the weaker, poorly-shaped trees, and give the stronger trees more sunlight and space.
This process imitates nature, where eventually many of the weaker trees would die naturally over time. The trees that are removed are used to make woodchips, posts and other products.
After a plantation is thinned a number of times, it is harvested, or clearfelled. In pine plantations this final harvesting typically takes place after 25 to 35 years, when the trees are of optimum size to produce a wide range of timber products, including building materials. Eucalypt plantations are either clearfelled after 10 to 20 years, and used mostly for woodchips, or they are thinned two or three times over 40 to 50 years to produce sawlogs.
The uniformity of plantations has allowed the development and introduction of new technology into the harvesting process. Excavators and feller-bunchers with specialised harvesting heads are now used to cut the trees, debark and de-limb them and cut them into specified lengths in one continuous operation. Forwarders with large, wide tyres or wide flat tracks (to reduce the impact of soil compaction) carry the timber to log landings
Case Study: Hi-tech system helps forecast wood production
controls transport
Photo: Forests NSW Image Library
The latest in computer technology is being used to forecast where wood is going to grow, and where it will be transported from NSW pine plantations. This system is called ‘Spatial Woodstock’ and allows Forests NSW to maximise revenue by supplying their customers with sawlogs in an efficient manner.
The models calculate how much timber is available, and where and when harvesting operations should be scheduled. The software also enables the standing volume of timber and the condition of the forest to be ascertained at any point in time. This enables forest managers to plan wood production over a 50 to 200 year period.
For more information about this innovative technology read the Bush telegraph magazine on NSW Department of Primary Industries website.
