SFF Project Summary

Project Title: Extend and improve the radiata pine calculator for farm foresters
Grant No.: 03/120
   

Contact Details

Name of Applicant Group: New Zealand Farm Forestry Association
Contact Person: Michael Halliday
Address: Raumati'
Patoka
RD
Napier
Telephone 1: 06 839 8819
Telephone 2:
Facsimile: 06 389 8919
Email: mm.hr@xtra.co.nz

Project Details

Status: finished
SFF Funding: 70,000
Total Project Funding: 231,000
Proposed Start Date: 2004-01
Proposed Finish Date: 2005-06
Region: Hawkes Bay
Sector: Forestry
Sub-sector: Farm forestry
Topic: Decision management and support


Email: mm.hr@xtra.co.nz
Final Report: Final Report
Updated: 02 March 2008

Update: September 2005

Introduction

This report covers five main items:

Training

Over the period June - September 13 training workshops were held throughout the country, attended by 140 users.

Locations and dates

Telford (Balclutha) 20-21 June
Christchurch 22-23 June
Richmond 24 June
Hastings 12 July
Masterton 14 July
Palmerston North 15 July
Auckland 19-20 July
Rotorua 27 July, 10 August
Blenheim 16 September

Based on the experience from these courses, effective promotion by several NZ FFA branches in each region would seem to be the key to getting a good turnout. In some areas such as Otago-Southland, Canterbury, and Auckland attendance was less than indicated by the number of license holders, and further workshops will no doubt be required.

Improvements

During the training courses, users provided many ideas for improvements. Those with the most merit and that could be readily dealt with have been included in upgrades. These will soon be released. The major improvements made so far are:

Scheduling on both DOS and crown length

Version 2 of the calculator permits users to schedule stands for pruning on the basis of diameter over stubs (DOS) or green crown length (GCL). In other words, if a target DOS of say 16cm is entered, the calculator estimates the age of the stand when that occurs. Similarly, a target crown length of say 4m can be entered, and the age is estimated when that occurs.

A new feature has been added that allows both a target DOS and a target green crown length to be specified at the same time.

When the new ‘Schedule for both’ button is pressed, the calculator reports the age and pruned height when both the target DOS and crown length are met.

This feature allows the user to control the DOS, and by specifying a safe crown length ensure the stand is not over-pruned. As pruned height is now a variable under this new facility, some care is necessary to ensure practical pruning lifts are being prescribed.
Additional costs

More flexibility has been added by permitting any number of additional costs to be named and details entered in the ‘Economics’ tab. An example is shown below.

Multiple runs now permits direct transfer from the user interface

A new button has been installed on the ‘multiple runs’ tab that copies values directly from the user interface to the first row of the multiple runs input sheet. This speeds up and eliminates errors in initiating batch runs.

Improved ‘Calibrate indices’

In the current version, use of the ‘calibrate indices’ facility has to follow any thinning. In the upgrade, the calibrate indices facility can be used regardless of when thinning occurs

‘Save as defaults’ made safer

An ‘are you sure’ warning has been added if the ‘save as defaults’ button is pressed on the user interface.

Other improvements

Comments fields have now been added to all the sheets used in the calculator- not just the user interface. Height growth has been added to the ‘Annual growth ‘ tab (this previously only displayed diameter, although the Douglas-fir calculator always displayed both diameter and height).

With the exception of the ‘Schedule for both’ button, these improvements have also been incorporated into the Douglas-fir calculator. It is intended to release the upgraded versions of both the radiata pine and Douglas-fir calculators during October- November 2005.

Update the manuals

The radiata pine manual has been updated, and the Douglas-fir manual will now follow suit.

Contribution from other organisations.

Attendees and local branches of the NZ Farm Forestry Association organized the training venues, and made financial contributions to the hire of the venues. In total the direct financial contribution to the eight courses was around $3000.

In addition considerable ‘in-kind’ contribution has been made in terms of time, telephone use, lunches etc. We estimate this contribution as 3 days/session, totaling 24 days contribution for this period.

The Douglas-fir Cooperative has contributed $3500 to Version 2 of the calculator during this period.

Publications

Bateson, J. 2005. The calculator revisited- every farm forester should have one. NZ Tree Grower, 26 (3) August, 2005 p16.
Knowles, R.L. 2005. Understanding the way trees reduce soil erosion. NZ Tree Grower, 26 (4) submitted.
Knowles, R.L. 2005 Calculator update. NZ Tree Grower, 26 (4) submitted.


June 3005

Introduction

This report covers the four main activities in this period:

Complete development of the Douglas-fir and radiata pine calculators V2.

The two calculators have been completed. An additional feature included in both calculators over this period includes a look-up table to convert decimal ‘growth’ years into calendar years. The remainder of the time has been spent in removing faults and getting them to run fault-free. This work has been done in conjunction with Dr Lars Hansen, Denmark.

Complete development of the manual for the Douglas-fir Calculator V2

Mr Piers Maclaren has been employed to co-author the manuals for the calculators. The manual for the radiata pine calculator was completed last quarter, and both have now been completed.

Distribute CDs and manuals to all licence holders.

Over 120 CDs have been burned and mailed to licence holders together with manuals. To make future upgrades easier to distribute, all licence holders for whom we do not hold an e-mail address have been written to requesting this information. A database has been set up holding this information.

Develop a training package and hold five training workshops in the South Island.

Five training workshops were held in the South Island over the week 20-24 June, with 47 persons attending as follows: 20 June Telford, Balclutha 7 persons 21 June Telford, Balclutha 11 persons 22 June University of Canterbury, Christchurch 5 persons 23 June University of Canterbury, Christchurch 8 persons 24 June Nelson-Marlborough Institute of Technology, Richmond 16 persons


30 September 2004

Introduction

This report covers the two main activities in this period:

Test versions of both calculators were released to a selected group of users on the 30th June, 2004. Over the past three months extensive use by the test group, and Forest Research staff, has led to various faults being corrected, and improvements made. The major changes are recorded below.

Maintain and improve an upgraded version of the Douglas-fir calculator.

A detailed report outlining the functions used in the calculator has been submitted to the New Zealand Douglas-fir Cooperative (Knowles, Hansen and Kimberley, 2004). This report is aimed at simplifying on-going maintenance of the calculator by recording the origin and details of all the underlying functions, and placing the otherwise widely dispersed knowledge into a single report.

An improved equation has been fitted that predicts starting values as a function of stand age, site index, stocking and SBAP (site basal area potential). This was found necessary, as there is currently very little data on the permanent sample plot system for stand ages less than 10 years, and the previous function was found to be over-predicting starting basal area and mean tree diameters for stands aged less than 14 years. The new function has been shown to be correct for stand ages 10-14 years, and the calculator has now been constrained to only run for stand ages of 10 years or more.

Functions linking stand mean DBH and tree stocking to root biomass/ha have been added, together with functions that decay the root biomass following thinning and clear felling. This work incorporates the role of tree roots illustrated in the ‘Green Solutions’ newsletter no 1, thus permitting version 2 of the calculator to readily estimate the role of sequential crops of Douglas-fir in reducing soil erosion on steep hill country, compared to other tree crops or pasture.

A new growth index - the 500 Index- has been developed for Douglas-fir, and included in the calculator. This is predicted from site index (mean top height at age 40 yrs) and SBAP (site basal area potential), and represents the mean annual volume increment (MAI) of a stand of Douglas-fir, planted at 1500-1650 stems/ha, thinned to 500 stems/ha around 15m MTH, and grown to 40 years of age. This index permits all sites to be directly compared for yield using a single number, rather than the two indices (Site Index and SBAP) previously used.

Maintain an upgraded version of the radiata pine calculator.

A detailed report outlining the functions used in the radiata pine calculator version 2 has been submitted to the New Zealand Forest and Farm Plantation Management Cooperative (Hansen, Knowles and Kimberley, 2004). This report is aimed at simplifying on-going maintenance of the calculator by recording the origin and details of all the underlying functions, and placing the otherwise widely dispersed knowledge into a single report.

Functions linking stand mean DBH and tree stocking to root biomass/ha have been added, together with functions that decay the root biomass following thinning and clear felling. This work incorporates the role of tree roots illustrated in the ‘Green Solutions’ newsletter no 1, thus permitting version 2 of the calculator to readily estimate the role of sequential crops of radiata pine in reducing soil erosion on steep hill country, compared to other tree crops or pasture.

Letters have been sent to nine organisations seeking permission to utilise their permanent sample plot data to validate the 300 Index growth model. This work will cover three distinct site types: sand dunes; summer-dry hill country; and higher rainfall fertile farm sites. Responses have been relatively slow in being returned, however all have been positive, with only one reply still to be received. It is intended this validation will be completed within the next quarter. The overall delivery dates will be unaffected.

APPENDIX 1. DOUGLAS-FIR CALCULATOR RELEASE NOTES

Version 2.0 July 2004

Lars W. Hansen and Leith Knowles

Introduction

These release notes describe the overall functionality and major changes to the Douglas-fir Calculator Version 2. They are intended as background reference and guidance for the users who will be testing the calculator prior to its release. A complete manual will be prepared when the calculator is released.

Version 2 of the Calculator has been developed as a joint undertaking between the NZ Farm Forestry Association, (with funding provided by the MAF Sustainable Farming Fund) and the NZ Douglas-fir Research Cooperative, with the later providing key technical information and additional funds.

Functionality

Major changes have been made to the underlying equations and formulations, as the growth model and all calculations are now embedded directly into the calculator. Furthermore, because the equations are much more complicated than the regression models of the first calculator, much of the new calculator has been programmed in Visual Basic for Applications (VBA). Because different versions of Excel treat VBA functions differently, this unfortunately means that the new version of the Douglas-fir calculator will work only in Excel 2000 and newer versions.

The user-interface

The main user-interface is similar to the old version of the calculator. The fundamental idea of keeping everything in one screen (input on the left, and output on the right) has been maintained (Figure 15), however with some alterations. The main differences are a range of additional input parameters, and corresponding output parameters, plus the addition of ‘buttons’ to activate some of the additional features. The extra features have also meant that the sensitivity facility of the old calculator has been replaced by the more powerful ‘Explorer’ facility (described later in these notes).

Additional input parameters and features are: 1) latitude, 2) up to five prunings, 3) up to five thinnings, and 4) up to five measurements. Additional facilities are: 1) schedule pruning with respect to diameter-over-stubs (DOS) or green crown length (GCL), 2) target a certain final crop stocking through adjusting the last thinning, 3) estimating the SBAP and site index from a single measurement, and 4) a choice of two log-grade specification tables.

Figure 1 - Screenshot of the user interface in the Douglas-fir calculator version 2

Basic stand parameters

The basic stand information (Figure 16) consists of six parameters: 1) SBAP, 2) site index, 3) initial stocking, 4) plant survival, 5) rotation age, and 6) the latitude. The addition of latitude originates from the implementation of an improved height/age curve, which includes latitude as an explaining variable.

Figure 2 - Stand information input

Pruning

The pruning input consists of five columns, one for each of up to five prunings (Figure 17).

Figure 3 - Pruning input

A pruning is defined by an age at pruning, the pruned height, and the number of pruned stems, and these must be input for the pruning to take effect. Additional features of the pruning facility are two scheduler functions activated by pushing the buttons in the left-most column. The ‘Schedule for DOS’-button activates a routine that through iteration finds the age of pruning that achieves a certain target DOS. The target DOS must be input individually for each of the prunings in the designated row. Scheduling on DOS automatically derives the relevant stand age, so any age present will be overwritten. The ‘Schedule for GCL’-button works in a similar manner, but targets a certain green crown length. Please note that sometimes the calculator is not able to achieve the exact target DOS or GCL, but settles on a near-by value or completely fails to achieve the target. It therefore pays to check the actual values reported in the pruning results (Figure 18).

Figure 4 - Pruning results

Thinning

The thinning facility (Figure 19) is similar to the pruning facility in that it allows up to five thinnings, each defined by its mean top height at thinning, stocking after thinning, thinning coefficient, and whether it is a production thinning, designated by entering a P, or for a thinning to waste, designated by entering a W. The thinning coefficient indicates the size of trees thinned, i.e. 1 = row thinning, <1 = thinning from below, and >1 = thinning from above. The default value for the first thinning is set at 0.71. A slightly higher value (up to 0.85) may be used for later thinnings. Details for determining this coefficient will be provided in the manual. If a P is set in the production/waste row, the thinned merchantable volume is distributed to log grades and assumed sold. Some statistics for each thinning are presented in the thinning results table on the right side of the screen (Figure 20). An additional facility is the button on the left in Figure 19, which activates a routine that iteratively adjusts stocking after the last thinning so that the target final crop stocking is achieved.

Figure 5 - Thinning input

Figure 6 - Thinning output

Measurements
The measurement facility (Figure 7) is for the purpose of adjusting the calculation to exactly resemble the situation in a real stand. Whatever numbers are input are considered to be correct, and the growth model projection is reset to pass through the inputted values. For example, should data be available from a mid-rotation assessment, the accuracy of the volume prediction at rotation age is enhanced in comparison to a prediction straight from planting to clear felling.

Figure 7 - Input for measurements

Calibration
The calibration facility (Figure 21) is for the purpose of estimating the site index and/or the SBAP for a particular stand based on one measurement of mean top height and basal area.

Figure 8 - Calibration facility

The calibration facility is activated by inputting the stand age at measurement, stand mean top height and stand basal area (m2/ha), and subsequently pressing either the ‘SBAP’ or the ‘Site index’ button. Always use the most recent measurement for calibration purposes, and do not enter these values in the measurement input area. The stand basal area can also be calculated from stand mean DBH and stocking by inputting these in the bottom table and pushing the button ‘Calc. BA’. For reference purposes, the stems/ha that the model predicts at the calibration age is displayed in the yellow cell. For the purpose of estimating SBAP, it is important that the stocking encountered at measurement, and the modelled stocking, are similar.

Other facilities
The ‘Restore defaults’-button (Figure 22) is equivalent to the keyboard command Ctrl-R in the old calculator. Pushing this button replaces all values in the input cells with a predefined set of default values. Unlike the first calculator, in version 2 the default values can be altered and customised by the user. Click on the tab at the screen base labelled ‘Default’.

Figure 9 - Button to restore defaults

Output tables
The output tables (the right side of the screen, and all coloured pink) are similar to those of the first calculator. More details are supplied with respect to pruning and thinning, of which most are self-explanatory. Because all the outputs are now estimated directly within the calculator, rather than using surfaces fitted to STANDPAK output, the results will differ from the previous version.

Log grades and the ‘Log specs’ tab
One of the major differences from the first calculator is the ability to use two sets of log grades, i.e. Grades A and Grades B. The desired log grade specification is activated through the checkboxes in the top of the table ‘Volume by log grades’ (Figure 23).

Figure 10 - Volume by log grades table

The log grades are defined and can be further customised under the ‘Log specs’ tab (Figure 12).

Figure 11 - Log specification tab

Only one pruned grade is allowed (and it must be the first column), and the second row in the log grade definition is to indicate which grade is pruned (1 = pruned, 0 = not pruned). The branch maximum is the diameter of the maximum branch in cm. The grade specific conversion is a scaling factor that reflects how much of a particular grade is normally converted into merchantable volume, i.e. similar to the conversion percent from the ‘User interface’, but applied individually to log grades. The percentage downgraded to poorest grade defines the percentage of each grade that is automatically turned into the grade occupying the column furthest to the right (usually pulp).

Figure 12 - Log grade specifications

Once the log grade specifications has been updated or changed it is necessary to transfer the new values to the system. This is done by pushing the button ‘Use update log specifications’.

Please make sure that any changes to the log grade specifications are compatible with the conversion percentage given in the ‘User interface’. Otherwise, the automatic scaling of the volumes by log grade with the conversion rate may give some very strange results.

Also note that the log-cutting algorithm processes the log grades from left to right. It is therefore important to input the log grades in order of value (price or preference) from left to right (as also indicated underneath the log specification tables).

The ‘Stand history’ tab
The ‘Stand history’ tab (Figure 24) reports the annual stand mean values for DBH, mean top height, mean height, stocking, basal area, and total green crown length of the stand (m/ha). To avoid unnecessary recalculation, the stand history is not generated before the button ‘Generate stand history’ is activated.

Figure 13 - Stand history tab

The ‘Economics’ tab
The economics tab is for more detailed definitions of key economic variables, and for more detailed reports on value by log grade and costs. The only user input required/available is the standard operation times for the waste thinning operation, which is split into several sub-operations and conversion factors. The default values are all medium/median values from the New Zealand Forest Service Work Study Standards.

The ‘Explorer’ tab
The explorer tab (Figure 25) is the replacement for the sensitivity facility in the first calculator. At first glance it may seem as a ‘step backwards’, but the explorer facility is extremely powerful once mastered. The main idea of the facility is the ability to automatically ‘process’ or ‘run’ several different stands or the same stand with different treatments in one operation.

Figure 14 - The 'Explorer' tab

In the ‘Explorer’ each row is equivalent to one stand. In the first four columns the stand conditions are defined, and the starting values are given in columns 5-7. The next nine columns are all for defining thinning operations (can be left empty if desired). In the example shown in Figure 25, two different options for the same stand have been defined. For the first stand the rotation age is 40 years, and the stocking after third thinning is 200 stems/ha. The second stand is kept one year longer, and the stocking is reduced to 100 stems/ha at the third thinning. Except for these differences the stands are exactly the same. To ‘process’ the list of stands, push the button ‘Calculate’. The standard excel facility to repeat rows with incremental values (select the row you wish to repeat and drag the box in the bottom-right corner) can be used with considerable advantage.

Once the ‘Calculate’ button is pushed, the ‘Explorer’ operates via the ‘User interface’ by substituting the values given in the table (Figure 25) into the user interface. All input variables in the ‘User interface’ that are not defined in the explorer table remain constant, and can thus be set manually before using the ‘Explorer’. Once the variables have been transferred onto the ‘User interface’, the model is run and the ‘Explorer’ reads off the results (DBH, MTH, Stocking, LEV etc.) and transfers those values back into the ‘Explorer’ output table, where the results can be evaluated and compared. The row with the highest LEV is automatically highlighted in red.

The ‘Estimate start BA’ button is for estimating the basal area at the starting age from age, stocking, site index and SBAP. The model behind it is only reliable for starting ages from 5-15 years.

The ‘Validator’ tab
The ‘Validator’ tab is similar to the ‘Explorer’ tab, but is tailored to process actual measurements rather than sensitivity analyses. The ‘Validator’ estimates SBAP and site index from one measurement (1st measurement), and forecast stand conditions at the time of the second measurement (2nd measurement). The predicted values and actual values at the second measurement are subsequently compared. The ‘Validator’ is mainly intended for processing data from permanent sample plots or growth plots, but can also be used as a quick way for estimating the SBAP for a list of stands measured during inventory.


APPENDIX 2. RADIATA PINE CALCULATOR RELEASE NOTES

Version 2.0 July 2004

Lars W. Hansen and Leith Knowles

Introduction

These release notes describe the overall functionality and major changes to the Farm Forestry radiata pine Calculator Version 2. They are intended as background reference and guidance for users who will be testing the calculator prior to its release. A complete manual will be prepared when the calculator is released.

Version 2 of the Calculator has been developed as a joint undertaking between the NZ Farm Forestry Association, (with funding provided by the MAF Sustainable Farming Fund) and the NZ Forest and Farm Plantation Management Research Cooperative, with the latter providing key technical information and additional funds.

Functionality

Major changes have been made to the underlying equations and formulations, as the growth model and all calculations are now embedded directly into the calculator. Furthermore, because the equations are much more complicated than the regression models of the first calculator, most of the new calculator has been programmed in Visual Basic for Applications (VBA). Because different versions of Excel treat VBA functions differently, this unfortunately means that the new version of the calculator will work only in Excel 2000 and newer versions.

The user-interface

The main user-interface is similar to the old version of the calculator. The fundamental idea of keeping everything in one screen (input on the left, and output on the right) has been maintained (Figure 15), however with some alterations. The major change is that the calculator no longer is updated continuously, but the user is required to push a ‘Run’ button in order to process the stand. Other differences are a range of additional input parameters, and corresponding output parameters, plus the addition of ‘buttons’ to activate some of the additional features. The extra features have also meant that the sensitivity facility of the old calculator has been replaced by the more powerful ‘Explorer’ facility (described later in these notes).

Additional input parameters and features are:
1) latitude and altitude,
2) up to five prunings,
3) up to five thinnings, and
4) up to five measurements.

Additional facilities are:
1) schedule pruning with respect to diameter-over-stubs (DOS) or green crown length (GCL),
2) target a certain final crop stocking through adjusting the last thinning,
3) estimating the 300 index and site index from a single measurement, and
4) a choice of two log grades.

Figure 15 - Screenshot of the user interface in the radiata pine calculator version 2

Basic stand parameters
The basic stand information (Figure 16) consists of six parameters: 1) 300 Index, 2) site index, 3) initial stocking, 4) plant survival, 5) rotation age, 6) altitude, and 7) latitude. The addition of altitude and latitude originates from the implementation of an improved national height/age curve, which includes both altitude and latitude as explaining variables.

Figure 16 - Stand information input

Pruning
The pruning input consists of five columns, one for each of up to five prunings (Figure 17).

Figure 17 - Pruning input

A pruning is defined by an age at pruning, the pruned height, and the number of pruned stems, and these must be input for the pruning to take effect. Additional features of the pruning facility are two scheduler functions activated by pushing the buttons in the left-most column. The ‘Schedule for DOS’-button activates a routine that through iteration finds the age of pruning that achieves a certain target DOS. The target DOS must be input individually for each of the prunings in the designated row. Scheduling on DOS automatically derives the relevant stand age, so any age present will be overwritten. The ‘Schedule for GCL’-button works in a similar manner, but targets a certain green crown length. Please note, that sometimes the calculator is not able to achieve the exact target DOS or GCL, but settles on a near-by value or completely fails to achieve the target. It therefore pays to check the actual values reported in the pruning results (Figure 18).

Figure 18 - Pruning results

Thinning
The thinning facility (Figure 19) is similar to the pruning facility in that it allows up to five thinnings, each defined by its age at thinning, stocking after thinning, thinning coefficient and whether it is a production thinning, designated by entering a P, or for a thinning to waste enter a W. The thinning coefficient indicates the size of trees thinned, i.e. 1 = row thinning, <1 = thinning from below, and >1 = thinning from above. The default value for the first thinning is set at 0.78. A slightly higher value (up to 0.85) may be used for later thinnings. Details for determining this coefficient will be provided in the manual. If a P is set in the production/waste row, the thinned merchantable volume is distributed to log grades and assumed sold. Some statistics for each thinning are presented in the thinning results table on the right side of the screen (Figure 20). An additional facility is the button on the left in Figure 19, which activates a routine that iteratively adjusts stocking after the last thinning so that the target final crop stocking is achieved.

Figure 19 - Thinning input

Figure 20 - Thinning output

Calibration
The calibration facility (Figure 21) is for the purpose of estimating the site index and/or the 300 index for a particular stand based on one measurement of mean top height and basal area (or dbh and stocking, or volume).

Figure 21 - Calibration facility

The calibration facility is activated by inputting the stand age at measurement, stand mean top height and stand DBH, or basal area or volume, and subsequently pressing either the ‘Estimate 300 index’ or the ‘Estimate site index’ button. Always use the most recent measurement for calibration purposes.

Other facilities
The ‘Restore defaults’-button (Figure 22) is equivalent to the keyboard command Ctrl-R in the old calculator. Pushing this button replaces all values in the input cells with a predefined set of default values. Unlike the first calculator, in version 2 the default values can be altered and customised by the user. Click on the tab at the screen base labelled ‘Default’.

Figure 22 - Button to restore defaults

Output tables
The output tables (the right side of the screen, and all coloured pink) are similar to those of the first calculator. More details are supplied with respect to pruning and thinning, of which most are self-explanatory. Because all the outputs are now estimated directly within the calculator, rather than using surfaces fitted to STANDPAK output, the results will differ from the previous version.

Log grades and the ‘Log specs’ tab
One of the major differences from the first calculator is the ability to use two sets of log grades, i.e. Grades A and Grades B. The desired log grade specification is activated through the checkboxes in the top of the table ‘Volume by log grades’ (Figure 23).

Figure 23 - Volume by log grades table

The log grades are defined and can be further customised under the ‘Log specs’ tab.

Only one pruned grade is allowed (and it must be the first column). The second row in the log grade definition is to indicate which grade is pruned (1 = pruned, 0 = not pruned). The branch maximum is the diameter of the maximum branch in cm. The grade specific conversion is a scaling factor that reflects how much of a particular grade is normally converted into merchantable volume, i.e. similar to the conversion percent from the ‘User interface’, but applied individually to log grades. The percentage downgraded to poorest grade defines the percentage of each grade that is automatically turned into the grade occupying the column furthest to the right (usually pulp).

Please make sure that any changes to the log grade specifications are compatible with the conversion percentage given in the ‘User interface’. Otherwise, the automatic scaling of the volumes by log grade with the conversion rate may give some very strange results.

Also note that the log-cutting algorithm processes the log grades from left to right. It is therefore important to input the log grades in order of value (price or preference) from left to right (as also indicated underneath the log specification tables).

The ‘Stand history’ tab
The ‘Stand history’ tab (Figure 24) reports the annual stand mean values for DBH, mean top height, mean height, stocking, basal area, and total green crown length of the stand (m/ha). To avoid unnecessary recalculation, the stand history is not generated before the button ‘Generate stand history’ is activated.

Figure 24 - Stand history tab

The ‘Economics’ tab
The economics tab is for more detailed definitions of key economic variables, and for more detailed reports on value by log grade and costs. The only user input required/available is the standard operation times for the waste thinning operation, which is split into several sub-operations and conversion factors. The default values are all medium/median values from the New Zealand Forest Service Work Study Standards.

The ‘Explorer’ tab
The explorer tab (Figure 25) is the replacement for the sensitivity facility in the first calculator. At first glance it may seem as a ‘step backwards’, but the explorer facility is extremely powerful once mastered. The main idea of the facility is the ability to automatically ‘process’ or ‘run’ several different stands or the same stand with different treatments in one operation.

Figure 25 - The 'Explorer' tab

In the ‘Explorer’ each row is equivalent to one stand. In the first five columns the stand conditions are defined, and the starting values are given. The next 15 columns are all for defining thinning and pruning operations (these can be left empty if desired). To ‘process’ the list of stands, push the button ‘Calculate’. The standard excel facility to repeat rows with incremental values (select the row you wish to repeat and drag the box in the bottom-right corner) can be used with considerable advantage.

Once the ‘Calculate’ button is pushed, the ‘Explorer’ operates via the ‘User interface’ by substituting the values given in the table (Figure 25) into the user interface. All input variables in the ‘User interface’ that are not defined in the explorer table remain constant, and can thus be set manually in the ‘User interface’ before using the ‘Explorer’. Once the variables have been transferred onto the ‘User interface’, the model is run and the ‘Explorer’ reads off the results (DBH, MTH, Stocking, LEV etc.) and transfers those values back into the ‘Explorer’ output table, where the results can be evaluated and compared. The row with the highest LEV is automatically highlighted in red.


Appendix 3. Farm Forestry Calculators

v2 for testing (June 2004)

Organisation

D-fir

P. rad

Individual recipient

Postal Address

Phone No.

Email

             
Carter Holt Harvey Forest Resources *   Paul Stevens CHH Forests, PO Box 300 380, Albany, Auckland (09) 414 0470 paul.stevens@chh.co.nz
City Forests Ltd * * Peter Oliver P O Box 2225, Dunedin (03) 455 9733 john@cityforests.co.nz
Ernslaw One Ltd * * Phil De La Mare / Steve Dowman PO Box 36, Tapanui

P O Box 13-264 Tauranga

(03) 204 8061

(07) 577 6100

p.delamare@ernslawtap.co.nz

steved@ernslawtga.co.nz

Mark Belton & Associates *   Mark Belton PO Box 1683, Christchurch (03) 366 7989 mark@beltonandassoc.co.nz
P.F. Olsen & Co Ltd * * David Thode / Jeff Schnell PO Box 975, Dunedin

P O Box 1127, Rotorua

(03) 455 8995 david.thode@pfolsen.co.nz

jeff.schnell@pfolsen.co.nz

Proseed NZ Ltd * * Shaf van Ballekom 177 Beach Road, Amberley RD 1 (03) 314 8978 seed@proseed.co.nz
JPS *   Jim Rydelius 9 Bullock Place, Burnside, ChCh (03) 358 7171 jrydelius@xtra.co.nz
Selwyn Plantation Board Ltd * * Hugh Stevenson PO Box 48, Darfield (03) 318 8311 hugh@spbl.co.nz
Kaingaroa Timberlands Ltd * * James Bullen / Bob Boardman P O Box 1284, Rotorua (07) 343.1070 james.bullen@tmclimited.co.nz
Wenita Forest Products Ltd * * Paul Greaves/ John Kerr PO Box 341, Mosgiel, Dunedin (03) 489 3234 paul.greaves@dn.wenita.co.nz
Wrightson Forestry Services * * Dennys Guild / Logan Negus Private Bag 1966, Dunedin

P O Box 540 Rotorua

(03) 471 9173 dwguild@ihug.co.nz

logannegus@wrightson.co.nz

Ruru Willis and Co Ltd * * Bruce Willis 160 Grey St, Gisborne (06) 868 6351 Willis@ruruwillis.co.nz
Southern Forests NZ Ltd *   Paul Molloy PO Box 92, Gore (03) 208 5522 info@southernforests.co.nz
Southland District Council   * Roger Washbourne P O Box 903 Invercargill (03) 218 7259 roger.washbourn@southlanddc.govt.nz
NZ Farm Forestry  Association * * Eoin Garden ‘Avenel’, Millers Flat, RD2, Roxburgh (03) 446 6560 eoin.garden@xtra.co.nz
NZ Farm Forestry  Association * * Angus Gordon Main Road South, RD3 Taihape. (06) 388 1571 ANGUSG@xtra.co.nz
NZ Farm Forestry  Association. * * Piers Maclaren 115 East Belt, Rangiora (03) 313 3756 piersmac@ihug.co.nz
NZ Farm Forestry  Association. *   Peter Brown Keith Road, RD 2, Rotorua (07 332 3218 prfs@wave.co.nz
NZ Farm Forestry  Association.   * Peter Davies-Colley Tittoki PDC, Private Bag, Whangarei (09) 433 1718 treepepl@igrin.co.nz
NZ Farm Forestry  Association * * Patrick Milne 75 Raddens Road, RD 2, Kaiapoi (03) 312 6599 Patrick@cypress.co.nz
NZ Farm Forestry  Association   * John Aitken Hau Ora,  R D 14, Havelock North (06) 874 7703 j.aitken@xtra.co.nz
NZ Farm Forestry  Association   * Stan Braaksma P O Box 41, Masterton (06) 378 2484 stan.braaksma@wrc.govt.nz
NZ Farm Forestry  Association   * Paul Cox 54 Forth St, Mataura, Southland (03) 203 3014 fts_pmcox@esi.co.nz
NZ Farm Forestry  Association * * Mike Halliday ‘Raumati’, Patoka, RD Napier (06) 839 8819 mm.hr@xtra.co.nz
Total 19 19