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Timber Catchments 1 and 2 and Bellingen Shire are covered by a total of 135 topographic maps at a scale of 1:25,000. These same maps were used for part of the 1994 study, where the boundaries of all private property were delineated. In addition, data on private forest areas derived from these maps was retained from the 1994 study. The area spreadsheets set out private forest areas in the following categories:
Previous consultancies undertaken by the authors on private property (mainly inventories) were also reviewed. Appendix 3 lists the 1:25,000 topographic maps where consultancies undertaken since 1989 were used to verify broad forest types. 4.1 Broad Forest Types Eleven (11) broad forest types were used in the 1994 study, as follows: Spotted Gum - a type dominated by Spotted Gum (Corymbia maculata), at times in almost pure stands but generally with a number of other eucalypts as associates. Spotted Gum/Blackbutt - a type usually dominated by Spotted Gum with Blackbutt (Eucalyptus pilularis) the more common of the associated species. Spotted Gum/Ironbark - A Spotted Gum type with Ironbarks (various species, including E. paniculata and E. siderophloia) being conspicuous amongst the associated species. Spotted Gum/Mixed Hardwoods - this type encompasses a range of mainly dry sclerophyll forest where Spotted Gum is common, the occurrence of other species dependent on soil type, location and aspect. Blackbutt - a type dominated by Blackbutt, at times in almost pure stands but generally with a number of other species as associates. Blackbutt/Bloodwood - a lower quality Blackbutt type with Bloodwood (usually E. gummifera) the other main species, often confined to drier, poorer quality forest. Blackbutt/Spotted Gum - a type dominated by Blackbutt with Spotted Gum the more common of the associated species. Blackbutt/Mixed Hardwoods - a mixed species type that can occur as dry or moist forest, with Blackbutt a common element. New England Hardwoods - mixed species forests of the higher altitudes and tablelands. Found as both dry and moist types, with New England Blackbutt (E. campanulata) often the common species along with a range of associated high altitude species (Tallowwood - E. microcorys and Sydney Blue Gum - E. saligna however are two species common to the coastal forests that are also found in these forest types). Moist Mixed Hardwoods - typical moist mixed forests of the coastal and hinterland areas, generally on the more sheltered aspects. Indicator species include Sydney Blue Gum, Tallowwood, Flooded Gum (E. grandis) and Brush Box (Lophostemon confertus). Dry Mixed Hardwoods - the typical coastal dry hardwood forests of the shallower soil types, ridgetops and exposed less favourable sites. Indicator species can include Ironbarks, Bloodwoods, Grey Gum (E. propinqua) and Grey Box (E. mollucana). For the text of this report, the 1994 forest types have been simplified further into five easily recognisable forest associations (note that the area and yield data in Appendices 5 and 6 is set out according to the 1994 forest types):
Appendix 4 is a series of photographs showing examples of the broad forest types. 4.2 Basic Site Quality Criteria The broad site quality criteria used in the 1994 Study were retained for this update. They are as follows: High Site Quality - forests on the better soils, higher rainfall, more sheltered locations. Included are the better quality moist mixed types, and the best examples of the Blackbutt, Spotted Gum and New England stands. Medium Site Quality - the typical average Blackbutt, Spotted Gum and New England hardwood stands and the poorer quality moist hardwood stands. In places these are also high site quality forest types that have been degraded by management practices. Low Site Quality - forests on heavier soil areas, poorer exposed or steep country or near the western limits of commercial growth. Because of soils, climate, topography or aspect these forests are slow growing and often the species mix is dominated by species of little or no commercial value. In some cases they are the drier forest types that have been degraded by management practices. 5. The Private Native Forest Area Gross, productive and net productive areas have been estimated for the private native forests with Timber Catchments 1 and 2 and Bellingen Sire. 5.1 Gross Area Using a map showing LGA boundaries overlain on a 1:25000 topographic map template, the 135 topographic maps from the 1994 study were reviewed to remove areas outside of Timber Catchments 1 and 2 and Bellingen Shire. Gross private forest areas were recalculated as necessary. Private properties that were known to have changed to Crown tenure since 1994 (through acquisition by State Forests of NSW or National Parks and Wildlife Service) were removed from the gross forest area. It is estimated that private forests cover a gross area of approximately 631,000 hectares. Table 5.1 sets out the gross area by LGA and broad forest type. It is further broken down by topographic map, 1994 forest types and site quality classes in Appendix 5. Estimated Gross Private Native Forest Area by Local Government Area and Broad Forest Type Click on the table below for a larger image in a new window 
5.2 Productive Forest Area Using the same 135 topographic maps, productive forest areas were determined by deducting from the gross areas obvious cleared and semi-cleared areas, swamps and wetlands, large areas of rocky or steep terrain and other known areas of non-commercial timber such as unproductive open woodland. In determining the minimum size of a productive timbered area, the size of the actual study area, the number and scale of topographic maps involved, and the complexity involved in measuring and mapping very small areas of forest had to be taken into account. For that reason there would be small individual areas of productive forest within the study area, of up to 50 or more hectares in size, that were not included in calculations. Similarly, despite the intensity of the survey and the many checks made, the classification of some areas as productive may be incorrect. However it could be reasonably expected that these two factors would balance out over such a large area. The productive forest area is estimated at approximately 517,000 hectares. Table 5.2 sets out the productive area by LGA and broad forest type. It is further broken down by topographic map, 1994 forest types and site quality classes in Appendix 5. Estimated Productive Private Native Forest Area by Local Government Area and Broad Forest Type Click on the table below for a larger image in a new window 
5.3 Net Productive Forest Area As with the 1994 study, the productive forest area estimates were reduced to a net area in order to calculate yields. Area reductions accounted for features not readily identified in the process of reducing gross area to productive area, such as: - small, scattered non-commercial or unproductive forest types; - small, scattered wetlands, swamps, cleared or semi-cleared areas; - additional areas identified as inaccessible, rocky or too steep; - reserved areas and rainforest stands; and - watercourse exclusion zones, such as filter strips and wildlife corridors. When these factors are considered, the largest area reductions are made for the low site quality areas. For example, the poorest New England forest types and the poorer dry coastal types (particularly in relation to the larger areas of non-commercial and nonproductive forest types). Conversely the higher quality forests require less of an area reduction. Based on the 1994 study, the range of area reductions applied to the productive forest areas was as follows:  The net productive forest area is estimated at approximately 363,000 hectares. Table 5.3 sets out the net productive area by LGA and broad forest type. It is further broken down by topographic map, 1994 forest types and site quality classes in Appendix 5. 6. Potential Hardwood Yields 6.1 Growth Rates Predicted growth rates (mean annual increment) adopted for the 1994 study were again used in this update. They include thinnings and residue pulpwood and are as follows:  Estimated Net Productive Private Native Forest Area by Local Government Area and Broad Forest Type Click on the table below for a larger image in a new window 
6.2 Estimated Total Potential Annual Yields Estimated total potential annual yields have been determined by applying the growth rates in section 6.1 to the net productive areas derived in section 5.3. They are set out by Local Government Area, broad forest type and site quality in Table 6.1. They are further broken down by 1994 forest types and site quality classes in Appendix 6. The estimated potential annual yields can be divided into two forest product categories: (a) pulpwood, including thinnings and forest residues (heads, butts and reject logs) and suitable for the manufacturing of a range of products; and (b) sawlogs (large and small), veneer logs, poles, piles and girders and salvage logs. Estimated Total Potential Annual Yields (cubic metres) by Local Government Area and Broad Forest Type Click on the table below for a larger image in a new window 
6.2.1 Estimated Potential Pulpwood Yields In managing private hardwood forests on a cutting cycle basis, retaining the best formed trees and thinning to produce the range of log types described in section 3.2, pulpwood will be generated from thinnings and forest residues. The proportion of pulpwood to better quality products will vary with forest type and stand quality, and generally will be higher in the poorer quality stands. Pulpwood yield in poorer stands would be as high as 75%, whilst in the better stands it may be as low as 33%. Indicative proportions based on site quality and broad forest types are set out below:  Estimated potential annual pulpwood yields have been determined by applying these proportions to the yield estimates in section 6.2 and are set out in Table 6.2. They are further broken down by 1994 forest types and site quality classes in Appendix 6. Estimated Potential Annual Pulpwood Yields (cubic metres) by Local Government Area and Broad Forest Type Click on the table below for a larger image in a new window 
6.2.2 Estimated Potential Yields of Sawlogs, Veneer, Poles, Piles, Girders and Salvage Logs The estimated potential annual yields of sawlogs, veneer logs, poles, piles and girders and salvage logs have been determined by deducting the estimated pulpwood yields in section 6.2.1 from the total estimated yields in section 6.2. The estimated potential annual yields for these products are set out in Table 6.3. They are further broken down by 1994 forest types and site quality classes in Appendix 6. Estimated Potential Annual Yields of Sawlogs, Veneer, Poles, Piles, Girders and Salvage Logs (cubic metres) by Local Government Area and Broad Forest Type Click on the table below for a larger image in a new window 
6.2.3 Proportions of Log Types other than Pulpwood Regrowth hardwood forests are capable of producing the full range of log types described in section 3.2 from cyclic thinnings as stands mature, diameters increase and gaps regenerate. The proportions of the various log types produced will depend on such factors as management techniques, forest type and site quality. Experience suggests that the possible proportions that might result from management aimed at say first thinning largely for pulpwood and optimising the production of higher grade products are as follows (they should be regarded as indicative only of possible yields.): 
Applying these indicative proportions to the yield figures in section 6.2.2 gives the following yields for the various log types. Possible Annual Yields of Logs other than Pulpwood (cubic metres) Veneer Logs Click on the table below for a larger image in a new window 
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