Eucalyptus nitens, recovery and economics of processing 15 year old trees for solid timber
Report Date: May 2015
Author: Dean Satchell, Sustainable Forest Solutions, R.D. 1 Kerikeri, Northland 0294
+64 9 4075525
Special thanks and acknowledgement go to:
- MPI Sustainable Farming Fund
- Neil Barr Farm Forestry Foundation
- John Fairweather Specialty Timbers
- North Canterbury, South Canterbury, South Otago and Southland branches of NZFFA
- NZFFA Eucalyptus Action Group
- NZFFA Research committee
Appendix 2: Sawn timber price estimates
Appendix 3: Literature review - Value-based survey pricing methods
Appendix 4: Literature review - Estimating profitability of growing E. nitens for solid timber production
Appendix 5: Sawmilling method
Appendix 6: Flooring price survey instrument
Appendix 7: Survey results table
Appendix 8: Survey analysis
Appendix 9: Wood physical properties, test results
Appendix 10: Glossary of terms
Appendix 11: Case study stand plot
Appendix 12: Comparison between levels of internal and surface checking
Appendix 13: Air drying experiment
Appendix 14: Sensitivity analysis
AS: Australian Standards 2796.1
Backsawn: See flatsawn.
Blanked: Dressed through a four-sider to dimensions approximately half way between green and fully profiled size.
Cant: Segment of a log that has been sawn on two or more faces to give final product width, but which requires further resawing to produce final thickness-dimensioned material.
Checking: Either of internal or surface checking.
Clears: Highest Farm Forestry Timbers grade, equivalent to Australian Standards select grade.
Clearwood: Wood devoid of defect or feature that lowers the grade.
Collapse: Excessive and uneven shrinkage causing corrugation of the wood surface. Characterised by a caved-in or corrugated ("washboarded") appearance of the wood surface. Flattening of single cells or rows of cells takes place during the drying or pressure treatment of the wood.
Concealed surface: The surface that is not exposed in a product (e.g. the underside of a floor board or bench top).
Corewood: Wood adjacent to and including the pith of the tree that is defective either because of decay, stress fractures or other causes that affect the physical performance of the wood. In this study distinguished by colour on the freshly sawn surface.
Cross cutting: The cutting of a tree trunk into logs.
Degrade: Feature that lowers the grade and therefore price of the wood.
Defect: Feature that does not meed grade requirements.
Docking: Cross cutting of boards into board pieces.
Dressing: Planing the surface of the wood to be smooth.
Edge-jointing: Finger jointing so that fingers are seen on the edge of the board but not the face. The joint seen on the exposed face is a line tangential to the edge of the board.
End-matching: Lumber that is end dressed and shaped to make a tongued-and-grooved joint at the ends when laid end to end.
Exposed surface: The surface graded for appearance.
Face cut: A cut made without using the saw bench's fence or sizing mechanism. An undimensioned cut which is used to produce a straight edge or face.
Feature: Distinctive natural and contrasting pattern inherent in timber.
Feature grade: The lowest Farm Forestry Timbers grade, equivalent to Australian Standards high feature grade.
FFT: Farm Forestry Timbers
Flatsawn: Timber is flatsawn (or backsawn) if the growth rings as seen from the end section meet the face of the board at an angle less than 45o with the board face.
Flitch: A large piece of sawn log intended for further cutting. A flitch may have two or more sawn edges but is not sawn to final dimension.
Green size: The size the board was sawn to.
High feature grade: One of three grades used in Australian Standards AS 2796.1. Equivalent to FFT feature grade.
Internal checking: For the purposes of this study "internal checking" is defined as where the check goes in from the surface more than 2mm on the 19mm profiled product on the cross section surface, or where the checks are inside the edge of the cross section surface.
Knotty core: The area of the log within the pruning wounds.
Nominal size: Size by which timber is known and sold in the market. The named size, which may vary from the actual size once dressed as a final product.
NPV: Net present value.
Price-size-gradient: The gradient whereby price per cubic metre increases or decreases according to log volume.
Profiled surface: The machined or dressed surface that is planed into the size and shape required for the final product.
Quartersawn: Boards sawn so that the annual rings, as seen from the end-section, form an angle of not less than 45o with the board face.
Residual value: The theoretical maximum amount the processor would pay for the log or product. Processing costs and required profits are deducted from the total price of the derived products.
Short: Short piece of sawn timber.
Slab: Timber that has been dimensioned to thickness but not width.
Slabbing: The process of cutting slabs, i.e. cutting faces for a sized thickness but not edges.
Select grade: Highest Australian Standards AS 2796.1 grade, equivalent to Farm Forestry Timbers select grade.
Standard grade: The next grade below select or clears grades.
Straightening cut: A second cut that straightens a board or flitch that previously curved from deflection.
Surface checking: For the purposes of this study "surface checking" is defined as either shallow checks that are seen on the surface of rough sawn timber and do not necessarily dress out on profiling, or checks less than 2mm deep and less than 1mm wide on the 19mm profiled surface.
Strip floor: A tongue and groove floor laid over joists.
T&G: Tongue and groove profile.
Wane: The absence of square wood on the edge of a board indicated by the underbark surface.
Want: Mechanical damage, including chipping
This chipping was caused by dressing the timber and needs to be docked out. damage caused by dressing the material.
Washboarding: The shape of the board surface resulting from uneven shrinkage caused by collapse.
Disclaimer: The opinions and information provided in this report have been provided in good faith and on the basis that every endeavour has been made to be accurate and not misleading and to exercise reasonable care, skill and judgement in providing such opinions and information. The Author and NZFFA will not be responsible if information is inaccurate or not up to date, nor will we be responsible if you use or rely on the information in any way.