Showing papers in "Australian Forestry in 1999"
TL;DR: In this paper, the authors proposed a new formula for calculating the Drought Factor and showed that it fits McArthur's meter to a far better degree than the previously published formula.
Abstract: Summary McArthur's Forest Fire Danger Meter (Mark 5) is a key tool for assessing broadscale fire danger throughout eastern Australia. The Drought Factor, an indicator of the fuel availability as calculated by the meter, is a key input in calculating the Forest Fire Danger Index. The currently accepted analytic method for calculating the Drought Factor is reviewed and shown to give significantly different results to that calculated by McArthur's meter. This paper proposes a new formula for calculating the Drought Factor and shows that it fits McArthur's meter to a far better degree than the previously published formula.
62 citations
TL;DR: In this article, fire history since 1850 was reconstructed by analysing tall wet eucalypt forest stands in the Warra long-term ecological research (LTER) site in southern Tasmania.
Abstract: Summary Fire history since 1850 was reconstructed by analysing tall wet eucalypt forest stands in the Warra long-term ecological research (LTER) site in southern Tasmania. Major fires occurred in 1898, 1906, 1914 and 1934. Fifty-seven percent of the forest has remained unburnt since 1850. Sixty percent of the forest burnt since 1850 occurs as mixed age stands, while 40 percent is pure regrowth. Ring counts of stumps of three veteran eucalypt trees indicated that the mature and oldgrowth forests of the Warra site represent a number of pre-1850 fires. One extant oldgrowth eucalypt stand was estimated to be over 450 years old. The common occurrence of multi-aged wet eucalypt stands has silvicultural implications where a management objective is to emulate pre-existing stand structures. While the fire history reported here is limited mainly to the period since 1850, it provides a good basis for understanding the current stand structures of the tall wet eucalypt forests of the Warra site. Such an understanding ...
60 citations
TL;DR: In this article, an historical perspective of silviculture in the native State forests of Victoria is presented covering the impacts of European settlement, initiation of active management, the application of methods based on sound ecological principles and, since the 1970s, a stronger focus on social and environmental objectives.
Abstract: Summary An historical perspective of silviculture in the native State forests of Victoria is presented covering the impacts of European settlement, initiation of active management, the application of methods based on sound ecological principles and, since the 1970s, a stronger focus on social and environmental objectives. The development of silviculture in the major forest types is discussed, including: ash, Low Elevation Mixed Species, High Elevation Mixed Species, Box-Ironbark and river red gum forests. Organisational arrangements for implementation of silviculture are described, along with processes for development of new and improved systems. The ongoing trend to improve on-ground delivery of silviculture through the use of new technology and the development of performance monitoring and improvement systems for sustainable forest management is also discussed.
55 citations
TL;DR: A single visit method of controlled crossing with the potential to greatly reduce the cost of producing pedigreed seed in the economically important species E. globulus and has the potential for use in mass pollination systems.
Abstract: Summary Previously, the production of controlled crossed seed in eucalypts required three visits to the female tree during the flowering season. We combined two novel methods from the literature involving pollinating cut styles at anthesis, and isolating individual styles with a tube to reduce the operation to a single visit. In E. globulus, this method has successfully produced seed at a rate and quality which was not significantly different from the established three visit method. However, the cut style treatment method was not successful when applied to E. nitens, the difference in success possibly being due to the difference in floral morphology between the two species. This single visit method of controlled crossing has the potential to greatly reduce the cost of producing pedigreed seed in the economically important species E. globulus and has the potential for use in mass pollination systems.
50 citations
TL;DR: A summary of the data available suggests that there is significant potential for damage to terrestrial vegetation from fire retardants, and to aquatic ecosystems from fire fighting foams, and there is a need to quantify the impacts of foams and retardants on native vegetation, and verify the effects of foam on aquatic organisms as mentioned in this paper.
Abstract: Summary The use of fire fighting chemicals in Australia is increasing, yet few data are available to allow evaluation of their potential environmental effects on Australian ecosystems. These chemical retardants and foams are used extensively in natural areas with high environmental value, and there is a need to evaluate the effects of the fire compared with the effects of the fire retardant and suppressant chemicals. A summary of the data available suggests that there is significant potential for damage to terrestrial vegetation from fire retardants, and to aquatic ecosystems from fire fighting foams. There is a need to quantify the impacts of foams and retardants on native vegetation, and verify the effects of foams on aquatic organisms. There is great potential for the use of foams for prescribed burning operations, as well as wildfire suppression, but its widespread use should be minimised until its potential ecological impacts can be assessed. Existing guidelines for handling foam in the field should ...
50 citations
TL;DR: The historical development of silvicultural practices in Tasmania is reviewed in this article for eucalypt forests, rainforests and blackwood forests, and partial harvesting techniques were developed and introduced in the 1980s for multi-aged forests with sparse understorey.
Abstract: Summary The historical development of silvicultural practices in Tasmania is reviewed for eucalypt forests, rainforests and blackwood forests. The silviculture of eucalypt forests prior to the 1950s was characterised by selective logging without any planned regeneration treatment. By the 1960s extensive research in the wet eucalypt forests resulted in the systematic application of silvicultural regimes based on clearfelling, slash burning and regeneration from seed trees or artificial sowing. This regime was extended to most eucalypt forest types throughout the 1970s with mixed results. Partial harvesting techniques were developed and introduced in the 1980s for multi-aged forests with sparse understoreys. Clearfelling remains the predominant regime in lowland wet eucalypt forests with a dense understorey. A range of partial logging methods are used for most drier and highland eucalypt forests. Over the last decade, 45% of native forest coupes on State forest had partial harvesting, 39% were clearfelled, ...
44 citations
TL;DR: Techniques for assessing and monitoring the decline and dieback of forest eucalypts are reviewed in relation to ecologically sustainable forest management.
Abstract: Summary In this paper techniques for assessing and monitoring the decline and dieback of forest eucalypts are reviewed in relation to ecologically sustainable forest management. The concept of ecologically sustainable management is a guiding philosophy being adopted for the management of all Australian native forests. An integral component of this strategy will be the ability to monitor forest health. This requires assessment of both the appearance of trees (canopy condition) and their underlying physiological status. However, visual assessment of eucalypt canopies can be misleading because of their opportunistic leafing phenology and epicormic regrowth characteristics. Several forest health assessment programs outside Australia now use multispectral imagery obtained by remote sensing. Such programs depend on relating spectral features with plant physiological properties such as chlorophyll content of the foliage. More recently chlorophyll fluorescence spectra have been related to the functioning of the p...
44 citations
TL;DR: The size and abundance of hollows increased with the size and age of the tree but there were apparent differences between species, and there was a similar difference between species in the numbers ofollows present in trees of different size.
Abstract: Summary Tree hollow development was studied in Eucalyptus pilularis (blackbutt) and Eucalyptus microcorys (tallowwood) in wet sclerophyll forests, and Eucalyptus signata (scribbly gum) in dry sclerophyll forest in south-east Queensland, Australia. In all three tree species hollow development appeared to be primarily initiated by fungal infection entering trees through dead branches and/or branch stubs rather than from fire scars. The process of hollow development appeared to commence when the trees were around 100 years old. The size and abundance of hollows increased with the size and age of the tree but there were apparent differences between species. Hollows were found in the majority (>50%) of E. pilularis trees above 100 cm dbh. By contrast most E. microcorys and E. signata larger than 80 cm dbh had hollows. There was a similar difference between species in the numbers of hollows present in trees of different size. E. pilularis trees 100–110 cm dbh had two hollows per tree but this number were presen...
44 citations
TL;DR: In this paper, the regeneration of E. regnans in the unburnt, mature forest is confronted by a phalanx of obstacles and the formation of large gaps which synchronously involve the overstorey, shrub understorey and fern stratum are an essential prerequisite for establishment.
Abstract: Summary This paper is based on observations on the regeneration of a mature E. regnans forest begun in 1949 and extending over the next 50 years. Any regeneration of E. regnans in the unburnt, mature forest is confronted by a phalanx of obstacles. The formation of large gaps which synchronously involve the overstorey, shrub understorey and fern stratum are an essential prerequisite for establishment, although success may not be assured unless the seedbed has been favourably prepared by mechanical disturbance or fire. In this study, regeneration, which was initiated experimentally by a heavy sowing of seed, scarification of soil, addition of nitrogenous fertilizer, creation of moderately good light conditions and the removal of competition by seedlings of understorey species in the first season, failed completely after 10–11 years even though understorey species which germinated from the soil seed bank continued to thrive. Processes of seed germination and seedling development are explored in terms of seed...
30 citations
TL;DR: This paper focuses on the semi-arid eucalypt woodlands, and the dry and wet sclerophyll forests of Western Australia.
Abstract: Summary This paper is one of a series that have been prepared to summarise the evolution of silvicultural practices in the native forests of Australia. It describes changes in silvicultural practices in the context of ecological characteristics of the species and changing perceptions of forest values and land use. This paper focuses on the semi-arid eucalypt woodlands, and the dry and wet sclerophyll forests of Western Australia. Data are presented which illustrate the impact of these practices on the forest in terms of intensity of disturbance.
25 citations
TL;DR: Eucalypt seedlings growing in Tasmanian forestry plantations can be damaged by the Bennett's wallaby (Macropus rufogriseus), Tasmanian pademelon (Thylogale billardierii), common brushtail possum (Trichosurus vulpecula) and rabbit (Oryctolagus cuniculus).
Abstract: Summary Eucalypt seedlings growing in Tasmanian forestry plantations can be damaged by the Bennett's wallaby (Macropus rufogriseus), Tasmanian pademelon (Thylogale billardierii), common brushtail possum (Trichosurus vulpecula) and rabbit (Oryctolagus cuniculus). This paper reports the results of damage surveys carried out during 1994 to 1997 at 32 Eucalyptus nitens and 3 Eucalyptus globulus plantations. Browsing damage was evident at all 35 plantations. The percentage of seedlings damaged ranged from 14 to 97% at six months after planting and from 17 to 100% at 12 months. Mean browse score (MBS) ranged from 0.2 to 3.8 at six months and from 0.2 to 4.7 at 12 months. There was a strong exponential relationship between these two measures of damage. Browsing damage was estimated to have reduced first-year E. nitens growth rates by between 12 and 100% (mean = 36, sd = 22.9). The mean percentage of seedlings recorded with browsing damage at plantations where 1080 poisoning operations had been carried out (12 mo...
TL;DR: In this paper, the authors present results of a Delphi survey which sought expert opinion about the growth of rainforest and Eucalyptus species in mixed-species plantations in North Queensland.
Abstract: Summary A brief outline is provided of the timber industry in North Queensland including a discussion of recent efforts to establish a plantation timber industry based on rainforest cabinet timbers to replace the industry lost with World Heritage listing in 1988. Results of a Delphi survey which sought expert opinion about the growth of rainforest and Eucalyptus species in mixed-species plantations in North Queensland are presented. Specifically, expert opinions about preferred species combinations and likely effects of mixed species plantations on timber yields are reported. Estimates of yield (m3 ha−1 y−1) and harvest age (years) are provided for 31 species commonly planted under the Community Rainforest Reforestation Program.
TL;DR: The Statewide Forest Resource Inventory (SFRI) as mentioned in this paper is the first comprehensive, standardised statement of the State's native forest resources, which will provide forest managers with resource information for making informed and consistent sustainable yield forecasts, and decisions on forest land-use planning and resource allocation.
Abstract: Summary The Victorian Department of Natural Resources and Environment has embarked on a major inventory project, which will provide the first comprehensive, standardised statement of the State's native forest resources. The Statewide Forest Resource Inventory (SFRI) will provide forest managers with resource information for making informed and consistent sustainable yield forecasts, and decisions on forest land-use planning and resource allocation. The SFRI project features detailed stand mapping from aerial photographs combined with model based, variable probability sampling of trees for stem size and defects, tree ring analysis for yield curve development and collection of data on tree hollows and other forest stand information for biodiversity and habitat modelling.
TL;DR: In this article, the development and current implementation of silvicultural practice in native State forests in New South Wales and how it can deliver ecologically sustainable forest management is reviewed and the requirements for providing long term sustainability of timber products to the timber industry and the conservation of biodiversity within native forests are often conflicting.
Abstract: Summary This paper reviews the development and current implementation of silvicultural practice in native State forests in New South Wales and how it can deliver ecologically sustainable forest management The requirements for providing long term sustainability of timber products to the timber industry, and the conservation of biodiversity within native forests are often conflicting As one means of resolving conflict, changes to silvicultural practices which take greater account of the ecological attributes of the forests are examined State Forests, as custodians of State forests in New South Wales, are developing systems to ensure silvicultural decisions are based on the best scientific, ecological and socioeconomic knowledge To be successfully implemented, these systems will need to satisfy economic, community and political expectations
TL;DR: To interpret, predict and manage these responses, such as fire-induced legume regeneration, it is necessary to identify the key fire, fuel and soil factors that affect heat transfer to the soil, and to determine functional relationships incorporating these factors.
Abstract: Summary Soil heating during forest fires gives rise to numerous ecological responses, many of which are poorly understood. To interpret, predict and manage these responses, such as fire-induced legume regeneration, it is necessary to identify the key fire, fuel and soil factors that affect heat transfer to the soil, and to determine functional relationships incorporating these factors. Heat transfer to the soil was investigated in the laboratory using jarrah forest litter as the heat source to develop a soil heating index for jarrah forest fires. Maximum soil temperature and heat load (the area beneath the temperature history trace) depended on the quantity of surface litter fuel consumed and soil and fuel moisture content, but was independent of fire rate of spread. A linear relationship incorporating these factors was developed to predict the maximum soil temperature at a depth of 10 mm, thus deriving the soil heating index. This relationship, together with knowledge of the temperatures necessary to ach...
TL;DR: In this paper, the role of silviculture in delivering sustainable forest management is discussed and some future challenges in native forest silv cultivation in a post-Regional Forest Agreement environment are presented.
Abstract: Summary Silviculture is the manipulation of forest stand structure and dynamics to achieve specific forest management objectives. In this paper the proceeding contributions from four State forest services about their silvicultural practices in native forests are introduced and reflected upon in the light of likely future directions in Australian forest management. Increasing ecological knowledge and changing social and economic demands on forests necessitate the continuous development and improvement of silvicultural practices. The role of silviculture in delivering sustainable forest management is discussed and some future challenges in native forest silviculture in a post-Regional Forest Agreement environment are presented. Reconciling management of native forests for biodiversity and for production of timber and non-timber products will be a major task, which may only be achieved through silvicultural planning at the landscape level. Further development and refinement of sustainability indicators will ...
TL;DR: Seed source within the natural range is concluded to be of minor importance for optimising growth in plantations of the species though the variation within seed sources may be important for future domestication and tree improvement.
Abstract: Summary Two series of Eucalyptus dunnii field trials were established at two locations in the north of Guangxi province in south central China between 1988 and 1991 to examine growth performance and genetic variation of trees from 10 natural seed sources. After four years, mean heights in the trials ranged up to 14.2 m and mean diameters at breast height up to 12.0 cm. Significant differences between seed sources existed for height and diameter and there were significant seed source by environment interactions in height and diameter across sites. However absolute magnitudes of differences between seed sources were small and changes in performance across sites were relatively unimportant. No one seed source showed absolute superiority at both locations across assessment ages. Seed source within the natural range is concluded to be of minor importance for optimising growth in plantations of the species though the variation within seed sources may be important for future domestication and tree improvement.
TL;DR: In the 4712 hectares of government-owned plantations affected, large-scale salvage operations were commenced quickly in order to minimise damage by the established exotic bark beetle Ips grandicollis Eichhoff and associated sapstaining fungi.
Abstract: Summary In late 1994, bushfires in the Beerburrum area north of Brisbane, in Queensland, Australia, damaged 8688 hectares of pine plantations (mostly Pinus elliotlii, P. caribaea and P. taeda). In the 4712 hectares of government-owned plantations affected, large-scale salvage operations were commenced quickly in order to minimise damage by the established exotic bark beetle Ips grandicollis Eichhoff and associated sapstaining fungi. The bark beetle began attacking fire-damaged trees 6 weeks after the fire and was significant in most areas at 10 weeks. Sapstain carried by I. grandicollis became significant at the completion of a life cycle of the insect (about 4 weeks in summer). Losses caused by I. grandicollis and sapstain following the fire were estimated at several million dollars Australian, mostly in privately-owned plantations where salvage was delayed for several months. Salvaged timber was stored on a 49 hectare site at Beerburrum under water spray to inhibit degrade of logs by insects and fungi. ...
TL;DR: In this article, a response to a scientific critique of current management of forests in southwest Western Australia by Wardell-Johnson and Horwitz (Forest Ecology and Management 85: 219-38, 1996) is presented.
Abstract: Summary This paper is a response to a scientific critique of current management of forests in southwest Western Australia by Wardell-Johnson and Horwitz (Forest Ecology and Management 85: 219–38, 1996). Their critique provides an inaccurate account of how these forests are managed as it overlooks the diversified nature of silvicultural and burning practices, the heterogeneous nature of disturbance caused by logging and fire, and the resulting landscape mosaic. This extensive spatial and temporal diversity in post-disturbance successional stages serves to facilitate recolonization of species displaced by logging or burning. We also suggest the Wardell-Johnson and Horwitz emphasis on the impacts of logging and fire on putative localized or endemic species is overstated. Ancient taxa of plants (lycopsids, ferns, cycads and conifers) may offer a more realistic example of species richness gradients than inadequately collected invertebrates.
TL;DR: Direct seeding sandalwood (Santalum spicatum) beneath 1–2 year old host (Acacia acuminata) seedlings was found to be a successful establishment technique at Northampton, but a high proportion of host trees had died, and the remaining trees were in poor health at the time of assessment.
Abstract: Summary Direct seeding sandalwood (Santalum spicatum) beneath 1–2 year old host (Acacia acuminata) seedlings was found to be a successful establishment technique at Northampton. Mean survival of S. spicatum rows ranged from 50 to 87%. after 8–9 years. Growth was also good, with mean stem diameter increasing at a rate of 4–7 mm yr−1, and mean estimated stem weight gaining 0.28–0.46 kg yr−1, between 4.5 and 9 years. However, a high proportion of host trees had died, and the remaining trees were in poor health at the time of assessment (November 1997). After 10 years. A. acuminata survival in rows seeded with S. spicatum in 1988 was significantly lower than rows seeded in 1989. Differences in host survival between S. spicatum planting years may be due to the initial period of growth without a root parasite, or the S. spicatum to host ratio. Growth of S. spicatum was also variable between planting years and provenances. At age 5.5. mean tree height of the Hazelby's provenance (194 cm) was significantly taller...
TL;DR: Levels of spread of wood discolouration and incipient decay associated with artificial stem wounds were studied in a provenance trial of Eucalyptus regnans and a progeny Trial of E. nitens to determine heritability estimates for lateral and longitudinal spread.
Abstract: Summary Levels of spread of wood discolouration and incipient decay associated with artificial stem wounds were studied in a provenance trial of Eucalyptus regnans and a progeny trial of E. nitens. Natural incidence of discolouration and numbers and sizes of kino veins were also examined in a provenance × fertiliser interaction trial in E. regnans. No differences were found between provenances of E. regnans for degree of spread of discolouration despite significant differences in tree diameter. However, incidence and size of kino veins differed between provenances of E. regnans. For E. nitens the spread of discolouration was less than that in E. regnans, and there were no significant differences in discolouration amongst the 10 open-pollinated families, or associated with tree diameter. Heritability estimates for lateral and longitudinal spread in E. nitens were relatively low and had large errors attached due to the small number of families sampled. Degree of lateral spread was correlated with tree diame...
TL;DR: In this paper, even-aged, mixed species eucalypt regeneration with a wide range of initial stockings was established on a Tasmanian moist sclerophyll site by using a range of sowing rates.
Abstract: Summary Even-aged, mixed species eucalypt regeneration with a wide range of initial stockings was established on a Tasmanian moist sclerophyll site by using a range of sowing rates. Stocking, growth and development were monitored on permanent measurement plots from the time of regeneration to age 16. Initial stocking data were combined with volume data from the age 13 and 16 measurements and used in conjunction with local expert knowledge on stand development to produce a preliminary model which predicts how initial stocking will affect the standing volume at any given age. This paper presents the model and outlines some other aspects of stand development for which the study, with its detailed information including the spatial location, species and size at repeated measurements of every tree on the plots, will provide a valuable data base.
TL;DR: A preliminary experiment is reported in which differences in the palatability of the foliage of individual E. ovata trees were tested, using cafeteria-style experiments with captive swamp wallabies and Tasmanian pademelons, showing strong and consistent preferences shown by both macropod species.
Abstract: Summary A preliminary experiment is reported in which differences in the palatability of the foliage of individual E. ovata trees were tested, using cafeteria-style experiments with captive swamp wallabies (Wallabia bicolor) and Tasmanian pademelons (Thylogale billardierii). Strong and consistent preferences were shown by both macropod species. These preferences were not correlated with any of the conventional measures of nutritional quality or putative defence compounds often made on Eucalyptus foliage. However, the preferences shown by these macropods correlate strongly with preferences shown by common ringtail possums (Pseudocheirus peregrinus), an interaction which is far better understood. Thus the same chemical factors may influence the palatability of the foliage for all three marsupial species. Continuing research on the relationship between chemical compounds in Eucalyptus foliage and the palatability of the foliage for browsing animals could potentially yield significant advantages in plantation...
TL;DR: Heterotrophic gain of carbon and mineral composition of Santalum album partnered singly in pot culture with three beneficial woody N2-fixing hosts and a non-beneficial eucalypt host is examined.
Abstract: Summary This paper examines heterotrophic gain of carbon and mineral composition of Santalum album partnered singly in pot culture with three beneficial woody N2-fixing hosts and a non-beneficial eucalypt host. Based on dry matter gains of the parasite at 33 weeks, Sesbania formosa proved the best host followed by Acacia ampliceps and A. trachycarpa while no improvement in growth was seen with Eucalyptus camaldulensis as a host in comparison with Santalum grown without a host. Numbers of haustoria formed by Santalum on roots of different hosts were poorly correlated with host quality. A small proportion of haustoria on legume hosts were attached to root nodules. Santalum partnered with any host or grown alone exhibited self-parasitism where haustoria attached to its own root system. Based on net C and N gains of Santalum and the C: N ratios of xylem solutes of Santalum, the heterotrophic gains of C from xylem of the three beneficial legume hosts over a nine week period were equivalent to 57.9% of total ca...
TL;DR: In this paper, a model-based approach was used to sample an area of 227,000 ha, using 271 plots, and significant relationships were found between sawlog volume and several stand descriptors, including elevation, crown cover, stand height and species.
Abstract: Summary Model-based sampling capitalises on relationships between the parameter of interest and other available data. In this inventory of the forests of North East Victoria, a model-based approach was used to sample an area of 227,000 ha, using 271 plots. Significant relationships were found between sawlog volume and several stand descriptors, including elevation, crown cover, stand height and species. A stratified random sampling approach would have required considerably more plots to achieve estimates of similar precision.
TL;DR: The three fires had no discernible effect on total taxa, total non-insects, Araneae (spiders), Acarina (mites), Collembola (springtails), total insects and Formicidae (ants), although activity of the Coleoptera (beetles) decreased significantly after the second and third fires while that of the Diptera (flies) increased over the same period.
Abstract: Summary The effects of three prescribed low intensity fires varying from means of 80 to 209 kWm−1 within six years on invertebrates in litter/upper soil were assessed. The 8.6 year study was based on 88 934 arthropod specimens, representing 35 ordinal or lower level taxa contained in 3520 pitfall trap samples from a site burnt three times in spring and an unburnt control site within a 30.7 ha area. The three fires had no discernible effect on total taxa, total non-insects, Araneae (spiders), Acarina (mites), Collembola (springtails), total insects and Formicidae (ants), although activity of the Coleoptera (beetles) decreased significantly after the second and third fires while that of the Diptera (flies) increased over the same period. However, as Coleoptera and Diptera activity on the unburnt control site decreased and increased respectively over the same period, it is uncertain whether the changes in activity were due to the fires or other non fire-related environmental factors. Futhermore, these change...
TL;DR: In this paper, the authors discuss the factors in the acquisition and utilisation of portable sawmills in the wood and paper industry in Australia and the advantages of using them over fixed-sited mills.
Abstract: Portable sawmills may potentially play an important role in the sawmilling industry in Australia. This paper discusses the factors in the acquisition and utilisation of portable sawmills. The contribution of small to medium sized sawmills to the wood and paper industry in Australia along with the advantages of portable sawmills over fixed-sited mills are outlined and discussed. A critical appraisal of the role of portable sawmills is undertaken which includes a discussion of recovery rates, costs, and throughput of fixed-site versus portable sawmills. A discussion of important aspects to consider in the decision to invest in portable sawmill technology is presented. These include reason for purchasing, types of sawmills available and their relative advantages, financing issues, power sources, maintenance, convenience and training.
TL;DR: Significant differences were found between species and between provenances within species for percentage of single stemmed trees and mean straightness ofsingle stemmed trees.
Abstract: Summary Sixteen provenances of spotted gum including eight provenances of Corymbia variegata, seven provenances of Corymbia maculata and one provenance of Corymbia henryi were assessed for growth, form and parrot damage in a trial south-west of Darkan, in Western Australia. C. henryi yielded the greatest mean annual volume increment at thirteen years (2.6 m'ha?1 yr1), followed by C. maculata (2.5 m3 ha−1 yr−1) and C. variegata (2.1 m3 ha−1 yr−1). Significant differences were found between species and between provenances within species for percentage of single stemmed trees and mean straightness of single stemmed trees. C. variegata yielded the highest average of 15.7% single stemmed trees, C. maculata, 11.6% and C. henryi, 4.5%. C. maculata yielded the straightest single stemmed trees (4.1 points out of a possible 6) followed by C. henryi (3.7 points) and then C. variegata (3.6 points). C. maculata sustained the lowest incidence of visible parrot damage with 55.9% of trees untouched. C. variegata and C. h...
TL;DR: This paper advocates the use of a linear programming tool called SPECTRUM and a GIS visualisation engine called SPECTRAVISION as an addition to a suite of tools that are used by State Forest of New South Wales, for regional scheduling of timber.
Abstract: Summary To schedule regional native forest timber harvesting at a strategic level, computer modelling tools are essential in determining the amount of timber cut through space and time. An understanding of silvicultural options of a forest resource and clearly stated management objectives are prerequisites to determining scheduling plans that can be sustained over many years, that is, ‘sustained yield’. However, to determine ‘sustainable yield’ other non-timber values have to be considered. This places more demands on the modelling capabilities of the tools used. This paper advocates the use of a linear programming tool called SPECTRUM (a management prescription allocation tool) and a GIS visualisation engine called SPECTRAVISION as an addition to a suite of tools that are used by State Forest of New South Wales, for regional scheduling of timber. Data from Eden Management Area in New South Wales are used as a case study to demonstrate the scheduling capabilities of SPECTRUM using land base information re...
TL;DR: A notable feature of this process is the increasing importance given to farm forestry by industry and government as mentioned in this paper, but research into the potential dimensions of this land-use and the possible outcomes is only at a preliminary stage, given unfavourable soils and low rainfall in much of Australia, and uncertain long-term economic returns in traditional forestry regions.
Abstract: Summary Forestry is being redefined to meet a broad range of economic, environmental and social expectations in many countries, including Australia. A notable feature of this process is the increasing importance given to farm forestry by industry and government. However, farm forestry is still in its infancy in Australia and research into the potential dimensions of this land-use and the possible outcomes is only at a preliminary stage. Given unfavourable soils and low rainfall in much of Australia, and uncertain long-term economic returns in traditional forestry regions, it is understandable that adoption of farm forestry has been slow, and viable self-sustaining regional farm forestry industries are still emerging. As landholders and industrial processors contribute to farm forestry development, it is reasonable to expect diverse farm forestry industries to emerge—with diversity in terms of the scale of operations, capital investment, biophysical and socioeconomic elements, the nature and extent of invo...