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WOODLOT for Windows 2.1 - Reference Manual | ||
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9.8 Natural - VDYP Specific Data WOODLOT uses the Ministry of Forests Variable Density Yield Projection yield model (VDYP batch version) to derive yields on naturally occurring stands. Please refer to a VDYP user manual or your Inventory forester to answer any specific questions you have on VDYP data or results. Enter inventory data in this area of the Polygon Data screen for current and future stands that either have not, or will not receive any significant management treatments. If you do not know, assume the stand will be natural. Most current stands older than 30 years of age will be naturally occurring, and have not received significant incremental silviculture treatments. VDYP is used for naturally occurring unmanaged stands, partial cut stands and stands that will be managed for deciduous species as well as coniferous This window will only appear if one of the yield types for the current polygon is set to VDYP. 
9.8.1 Site Index Acceptable Values: Positive decimal Site Index may be entered manually, or derived by VDYP. Enter a known site index (meters at reference age 50 years) in the text box, which is available from forest cover maps, and inventory FIP files or silviculture records. Alternately, you may have the site index (SI) derived by VDYP by entering height and age in the next few fields. Site Index MUST be entered for stands younger than 30 years, and cannot be calculated. The site index will change to a cyan (light blue) colour if the calculated site index is different from the one entered. The calculated site index will not be displayed as 0 on the polygon screen but, will have its calculated value displayed in the Yield Table and Harvest Parameters window. Note: if stand height and total age are entered, then site index is determined from these values, and will override any manually entered site index. That is, stand height and age override any manually entered site index value. Refer to section "9.3.2 View Existing Yield" page 9-42 9.8.2 SI(tot)Age Acceptable Values: Positive integer This value should only be entered if:
Enter the average age of dominant species that have been measured for Site index. Caution: Use SI (total) Age ONLY IF the stand is older than 30 years. 9.8.3 SI Height Acceptable Values: Positive decimal This value should only be entered if:
Enter the average height of dominant species that have been measured for Site index. Caution: Use SI Height ONLY IF the stand is older than 30 years. 9.8.4 Crown Closure Acceptable Values: Positive integer Enter the Crown Closure as a percent (e.g. enter 62 for 62%) from the forest cover map. Refer to the VDYP manual or "Appendix 4 - VDYP Limits and Defaults" for default Crown Closures if you do not know. 9.8.5 PSYU Acceptable Values: Positive integer Enter the PSYU number for the area around your Woodlot. The PSYU number is used to reduce gross volumes for waste and breakage. Note a "0" PSYU will derive a volume with no reduction for waste and breakage. Find PSYU: If you do not know the PSYU (or FIZ), but do know the inventory region and compartment, the PSYU can be found by WOODLOT. For more information please see section "9.2.5 Find PSYU" page 9-39. 9.8.6 PSYU Block Acceptable Values: Single character WOODLOT Extra (must be turned on in the settings screen) Note:Generally this variable is not used, as only some areas of the province have PSYU Blocks. If you do not know the PSYU block, but do know the inventory region and compartment, the PSYU block can be found by WOODLOT, though it will not be displayed. For more information please see section "9.2.5 Find PSYU" page 9-39. Only some areas have a PSYU Block. 9.8.7 VAF Acceptable Values: Positive decimal The Volume Adjustment Factor (VAF) can be used to scale the VDYP volume up or down depending on the actual growth you observe for your polygon. For example, if volumes recovered or cruised are typically greater by 10%, enter 1.1; conversely, if volumes are typically lower by 20%, enter 0.8. This can only be used for VDYP yields. Normally this will remain 1.00. WARNING: DO NOT ADJUST THE VAF UNLESS YOU CAN DEMONSTRATE THE VARIABILITY IN YOUR INVENTORY INFORMATION! 9.8.8 Stocking Class Acceptable Values: 0, 1, 2, 3, 4, R Select the Stocking class for your polygon. Stocking Class 0 is treated the same as 1 in VDYP. Stocking class R is used for a residual stand. 9.8.9 Species Up to 6 VDYP species can be added in order of dominance. Either enter the two digit species code, or allow it to be automatically entered using the drop down buttons. Refer to "Appendix 7 - Species" for a complete listing of species available in WOODLOT. Non-commercial species such as pacific western yew generally have zero volume in the yields compiled by VDYP, though these species are included for comparability with MOF FIP files. 9.8.10 Species Percent Acceptable Values: Positive integer Enter the percent by species to a total of 100%. The boxes will be a yellow colour if the species do not add up to 100%. Double click on the percent box to automatically allocate the remaining percent to this species, or enter in the correct number. 9.8.11 Netting Out VDYP Species WOODLOT Extra (must be turned on in the settings screen) This feature is used to net out VDYP species from the harvest calculation. It may only be used for clearcut polygons. 
Next to the species percent are a series of check boxes. They must be checked on to have the species included in harvest calculations. Click on the check box to clear it if you wish the volume netted out of harvest calculations. If you choose to net out a species (check box is empty), the polygon MUST be converted to a TIPSY polygon for future management. Note: The yield table displays the total volume for the polygon, not the net volume. This function may be updated in a future release of WOODLOT. The amount that normally contributes by species is shown in the yield table. | ||
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