FOREST YIELD - HARVESTING SYSTEM
Since 1998, the silvicultural system employed by Lindsay & Dixon in managing the Longwood and Rowallan beech forests was an area-based control mechanism which utilised a regular two-hectare grid imposed on the forest with one quarter of the grid (1/2 hectare) being harvested.
Following extensive research on the growth and regeneration of previously harvested forest areas, the Company in collaboration with the Ministry of Primary Industries (MPI) has trialed other methods of harvesting including single tree and small gap harvesting (gaps or small coupes averaging 500m2 in size) with the intent of spreading the canopy openings more evenly and consistently across the forest estate. Canopy openings and more particularly the size of the canopy openings, play a very important part in the regeneration cycle by ensuring light and the opportunity for new seedling establishment and regeneration is possible.
It is evident over the past 18 years of harvesting operations that there is no single process that achieves the ultimate goal of consistent regeneration and growth, rather there is a combination of the various harvesting methodologies, including large coupe areas to single tree and small gaps, depending on the terrain, topography and characteristics of individual forest areas.
Lindsay & Dixon will continue to research and expand its knowledge and data base of these regenerating forests and will review and amend their silviculture and harvesting processes in collaboration with MPI, Landcare Research and other specialist forestry experts to ensure the purpose of the Forest Act ‘to ensure the sustainable forest management of indigenous forest land’ is achieved.
The spatial framework for this system relies on geographic features - waterways, roads and tracks - to delineate Tree Selection Areas (TSAs) within which specific tree selection, forest structure and production objectives are to be met. This system also provides the spatial framework for yield control and record-keeping.
The FERIS System (FOREST AND ENVIRONMENTAL RECORD AND INFORMATION SYSTEM).
The FERIS system is a digital forest management record and information system which also includes a geographical information system (GIS). The system was custom built and installed expressly for Lindsay & Dixon to better manage all the various facets of sustainable forest management. It includes stakeholder registers, a log to record communications with stakeholders, approved policies, procedures and guidelines, yield control mechanisms and records, permanent sample plot and photo point records, orthophotography and various mapping data. Considerable resources have been employed in building the system which was installed in June 2005.
Stream & Water Monitoring
Stream monitoring has been in place now since 2005 with nine sampling sites established. Five of these sites are within the forest estate and the other four are just outside the boundary of the forest. These are all long-term monitoring sites for measuring water temperature, solids and turbidity. Two additional short-term sites have been recently established in the area of current operations in order to detect any impacts from these harvesting operations.
Results to date indicate no meaningful trends outside of background (natural) events.
Growth Monitoring
A key requirement of the Ministry of Primary Industries Indigenous Forest Unit and the certification auditors is to improve the quality and reliability of the original growth estimates of the forest. A Permanent Sample Plot methodology has been developed and a number of plots established to determine growth rates of the predominant species (Silver beech) and other compositional changes within the forest.
Field Visits
Lindsay & Dixon Ltd have hosted a number of field visits over the years. Following on from such a visit by the then Minister of Forestry, Hon Jim Sutton, Lindsay and Dixon hosted the local branch of the New Zealand Farm Forestry Association and organised a field trip for its members to view the forest operations as well as the Company's sawmill and processing facilities at Tuatapere in August 2004.
Then in February this year, the current Minister of Forestry, Hon Jim Anderton, together with a number of forestry officials and local authority staff joined the Lindsay & Dixon Directors and the Chairman of Waitutu Incorporation (the forest owners) in a comprehensive tour of all the Lindsay & Dixon operations and facilities.
Such visits are vital in promoting the sustainable management of NZ indigenous forests and in raising the awareness of all stakeholders on the realities, benefits and issues of this small but important industry.
1 'Normal' in this context means that the diameter class (or age class) distribution is close to that of the classic 'reverse J' curve with high numbers of seedlings and small trees at one end through to just a few big old trees at the other.
