Solid timber recovery and economics of short-rotation small-diameter eucalypt forestry
This report was prepared for Future Forests Research Ltd (FFR) by Scion.
Dean Satchell, Sustainable Forest Solutions, R.D. 1 Kerikeri, Northland 0294. +64 9 4075525
James Turner, Scion, Private Bag 3020 Rotorua 3010. +64 7 3435899
Date: June 2010
Appendix 1: Assumptions in Discounted Cash Flow Analysis
Appendix 2: Prices and values of timber in New Zealand used for estimating board prices
Appendix 3: Timber grading
Appendix 4: Sawmilling methodology
Appendix 5: Glossary of terms
Spreadsheet 1: Kaingaroa Compartment 1194 E. regnans economic value (Microsoft Excel macro-enabled workbook 3.6 MB)
Spreadsheet 2: Optimal rotation and stocking for E. regnans (Microsoft Excel macro-enabled workbook 864 KB)
Treegrower article »
Appendix 5: Glossary of terms
Back-sawn: Timber is known as back-sawn if the growth rings meet the face of the board at an angle less than 45o (Bootle 1983).
Blanked: Timber machined to four sides in preparation for finished dimension profiling.
Blanks: Laminated panels sold as a dimensioned product suitable for further sizing and finishing into a more specific end-use.
Bow: The lengthwise curvature of the broad face of a piece of timber.
Back-sawing: Sawing timber so that the annual rings, as seen from the end-section, form an angle of less than 45o with the board face.
Box grade: Timber rejected as not meeting the grading rules.
Cold-climate eucalypts: For this study, species within the ash group of eucalypts and Eucalyptus nitens.
Collapse: Excessive and uneven shrinkage causing corrugation of the wood surface. Also known as washboarding.
Conversion return: A log recovery value which represents the theoretical maximum amount to pay for logs delivered to the sawmill (Alzamora & Apiolaza 2010). It is estimated from the value of the timber recovered from the log minus the cost of harvesting, cartage, and sawmilling.
Edge: The narrow longitudinal surface usually at right angles to the face of a piece of timber.
Face: The wide longitudinal surface usually at right angles to the edge of a piece of timber.
Fillet-stick: Used for separating layers for drying.
Flat-sawn: Timber sawn so that the annual rings, as seen from the end-section, form an angle of no less than 30o with the board face.
Indistinct: Not obviously different in appearance.
KAR: Knot area ratio. The area of the knot as a ratio of the area of the timber cross section.
Kerf: The width of the saw cut removed by the saw blade.
Nominal: The named size which may vary from the actual size of the piece of wood because of variations due to sawing, shrinkage and dressing and the tolerances allowed for these operations.
Quarter-sawn: Boards cut with their faces parallel to the rays. For normal milling, an angle of not less than 45o is acceptable in quarter-sawn material (Bootle 1983).
Quarter-sawn, fully: When the growth rings show an angle not less than 80o to the face of the board.
SED: Small end diameter.
Shakes: Breakage or longitudinal separation of wood fibres due to causes other than drying, originating in the log.
Shook: Small length of timber suitable for finger-jointing.
Skip: An area that failed to dress.
Slab: Timber which has been dimensioned to thickness but not width.
Slabwood: waste wood resulting from sawmilling.
sph: Stems per hectare.
Spring: Also known as crook. The lengthwise curvature of the edge of a piece of sawn timber.
T & G: Tongue and groove profile.
T G & V: Tongue, groove and V profile used for panelling.
Wane: The absence of wood indicated by the underbark surface.
Want: The absence of wood, other than wane, from the arris or surface of a piece of timber.
Disclaimer: This report has been prepared by New Zealand Forest Research Institute Limited (Scion) for Future Forests Research Limited (FFR) subject to the terms and conditions of a Services Agreement dated 1 October 2008.The opinions and information provided in this report have been provided in good faith and on the basis that every endeavor has been made to be accurate and not misleading and to exercise reasonable care, skill and judgement in providing such opinions and information. Under the terms of the Services Agreement, Scion's liability to FFR in relation to the services provided to produce this report is limited to the value of those services. Neither Scion nor any of its employees, contractors, agents or other persons acting on its behalf or under its control accept any responsibility to any person or organisation in respect of any information or opinion provided in this report in excess of that amount.