Pollination methods, stigma receptivity and pollen tube growth in Eucalyptus argophloia

Eucalyptus argophloia Blakely (Western white gum) has shown potential as a commercial forestry timber species in marginal environments of north-eastern Australia. We measured early pollination success in Eucalyptus argophloia to compare pollination methods, determine the timing of stigma receptivity and compare fresh and stored pollen. Early pollination success was measured by counting pollen tubes in the style of E. argophloia 12 days after pollination. We compared the early pollination success of 1) Artificially Induced Protogyny (AIP), one-stop and three-stop methods of pollination; 2) flowers pollinated at 2 day intervals between 2 days before and 6 days after anthesis and 3) fresh pollen and pollen that had been stored for 9 months. Our results show significantly more pollen tubes from unpollinated AIP and AIP treatments than either the one-stop pollination or three-stop pollination treatments. This indicates that self-pollination occurs in the unpollinated AIP treatment. There was very little pollen tube growth in the one-stop method indicating that the three-stop method is the most suitable for this species. Stigma receptivity in E. argophloia commenced six days after anthesis and no pollen tube growth was observed prior to this. Fresh pollen resulted in pollen tube growth in the style whereas the stored pollen resulted in a total absence of pollen tube growth. We recommend that breeding programs incorporating E. argophloia as a female parent use the three-stop pollination method, and controlled pollination be carried out at least six days after anthesis using fresh pollen.

Spotted gum (plantations)

Spotted gum is an important commercial tree in Queensland that produces a high quality, hard, durable and attractive timber. Currently, spotted gum is the highest volume native hardwood harvested in Queensland and has been used for construction, engineering, appearance products and round timbers. Spotted gum timber has a well-established market, and is in demand both nationally and internationally.

Red mahogany (plantations)

Red mahogany produces a hard, durable and attractive timber. In the past, small quantities of timber harvested from native forest has been used in construction, engineering and for appearance products and round timbers. It has well-established national markets, particularly in Queensland and NSW. It is also known in the international market as it is grown in plantations in other tropical regions.

Western white gum (plantations)

Western white gum produces a hard, heavy, durable and attractive timber that is potentially suitable for construction, appearance products and round timber products. It is no longer harvested from natural stands but is a productive plantation tree in Queensland. It is highly suitable for low rainfall areas in northern Australia and is frost and drought hardy, has good form and reasonable growth rates. It is generally unknown in either national or international markets.

Hoop pine - Araucaria (plantations)

Hoop pine is a native species and a well-established commercial plantation tree in Queensland that produces a premium grade, quality tropical softwood. It is valued for uniform, knot-free timber with exceptional quality, and used for many commercially important wood products. Hoop pine has a well-established market and is in demand both nationally and internationally. High-grade sawn hoop pine serves the upper end of the domestic market, taking advantage of long lengths of clear wood, and exports include sawn wood and woodchip.

Southern pine (plantations)

Southern pine is a well-established group of commercial plantation species in Queensland and produces a premium grade, quality softwood. The southern pines group is valued for excellent growth, straightness, minimal branching, wood density and even wood texture. Southern pine timber products have a well-established processing industry and market in Queensland. It is in demand both nationally and internationally. High-grade sawn wood serves the upper end of the domestic market and exports include sawn wood and woodchip.

Structural Veneer Based Composite Products from Hardwood Thinning - Part II: Testing of Hollow Utility Poles

Australian utility pole network is aging and reaching its end of life, with 70% of the 5 million poles currently in-service nationally installed within the 20 years following the end of World War II. The estimated investment required for the replacement or remedial maintenance of the aging 3.5 millions poles is as high as 1.75 billion dollars. Additionally, an estimated 21,700 high-durability new poles are required each year, representing further investment of 13.5 million dollars per year. Yet, agreements which progressively phase out logging of native forests around Australia have been signed, giving the industry about 25 years to make the transition from Crown native forests to plantations and private forests. As utility poles were traditionally cut from native forest hardwood species, finding solutions to source new poles currently presents a challenge. This paper presents tests on Veneer Based Composite hardwood hollow utility poles manufactured from Gympie messmate (Eucalyptus cloeziana) plantation thinning. Small diameter poles of nominal 115 mm internal diameter and 15 mm wall-thickness were manufactured in two half-poles butt jointed together, using 9 veneers per halfpole. The poles were tested in bending and shear, and experimental test results are presented. The mechanical performance of the hollow poles is discussed and compared to hardwood poles cut from mature trees and of similar size. Future research and different options for improving the current concept are proposed in order to provide a more reliable and cost effective technical solution to the current shortage of utility poles. © RILEM 2014.

Structural Veneer Based Composite Products from Hardwood Thinning - Part I: Background and Manufacturing

In Australia, plantation forests have increased in area by around 50% in the last 10 years. While this expansion has seen a modest 8% increase for softwoods, hardwood plantations have dramatically increased by over 150%. Hardwood plantations grown for high quality sawn timber are slow to mature, with a crop rotation time potentially reaching 35 years. With this long lead-time, each year the risk from fire, pests and adverse weather events dramatically increases, while not translating into substantially higher financial returns to the grower. To justify continued expansion of Australia's current hardwood plantation estate, it is becoming necessary to develop higher value end-uses for both pulpwood and smaller 'sawlog' resources. The use of the low commercial value stems currently culled during thinning appears to be a necessary option to improve the industry profitability and win new markets. This paper provides background information on Australian forests and plantations and gives an overview of potential uses of Australian hardwood plantation thinning logs, as their mechanical properties. More specifically, this paper reports on the development of structural Veneer Based Composite (VBC) products from hardwood plantation thinning logs, taking advantage of a recent technology developed to optimise the processing of this resource. The process used to manufacture a range of hollow-form veneer laminated structural products is presented and the mechanical characteristics of these products are investigated in the companion paper. The market applications and future opportunities for the proposed products are also discussed, as potential benefits to the timber industry. © RILEM 2014.

Estimates of genetic parameters for growth and wood properties in Eucalyptus pellita F. Muell. to support tree breeding in Vietnam

Key message Eucalyptus pellita demonstrated good growth and wood quality traits in this study, with young plantation grown timber being suitable for both solid and pulp wood products. All traits examined were under moderate levels of genetic control with little genotype by environment interaction when grown on two contrasting sites in Vietnam. Context Eucalyptus pellita currently has a significant role in reforestation in the tropics. Research to support expanded of use of this species is needed: particularly, research to better understand the genetic control of key traits will facilitate the development of genetically improved planting stock. Aims This study aimed to provide estimates of the heritability of diameter at breast height over bark, wood basic density, Kraft pulp yield, modulus of elasticity and microfibril angle, and the genetic correlations among these traits, and understand the importance of genotype by environment interactions in Vietnam. Methods Data for diameter and wood properties were collected from two 10-year-old, open-pollinated progeny trials of E. pellita in Vietnam that evaluated 104 families from six native range and three orchard sources. Wood properties were estimated from wood samples using near-infrared (NIR) spectroscopy. Data were analysed using mixed linear models to estimate genetic parameters (heritability, proportion of variance between seed sources and genetic correlations). Results Variation among the nine sources was small compared to additive variance. Narrow-sense heritability and genetic correlation estimates indicated that simultaneous improvements in most traits could be achieved from selection among and within families as the genetic correlations among traits were either favourable or close to zero. Type B genetic correlations approached one for all traits suggesting that genotype by environment interactions were of little importance. These results support a breeding strategy utilizing a single breeding population advanced by selecting the best individuals across all seed sources. Conclusion Both growth and wood properties have been evaluated. Multi-trait selection for growth and wood property traits will lead to more productive populations of E. pellita both with improved productivity and improved timber and pulp properties.

Plantation crops

Plantation horticulture is an important part of the economic landscape of many tropical countries. Plantations were developed in association with colonial expansion and the original models were based on the production of monocrops which had a ready export market, using cheap or slave labour. Plantations in the twenty first Century are less likely environments for exploitation of human and environmental capital. They are however, linked to crop production on a large scale for produce to be sold, at profit, for export to distant markets rather than local sale. A range of crops can be broadly categorized into plantation crops. Plantations continue to be effective models for efficient agricultural production and will evolve in response to the continued demand for food, fruit, fibre, oil crops and timber from a growing population

Efficient eucalypt cell wall deconstruction and conversion for sustainable lignocellulosic biofuels

In order to meet the world’s growing energy demand and reduce the impact of greenhouse gas emissions resulting from fossil fuel combustion, renewable plant-based feedstocks for biofuel production must be considered. The first-generation biofuels, derived from starches of edible feedstocks, such as corn, create competition between food and fuel resources, both for the crop itself and the land on which it is grown. As such, biofuel synthesized from non-edible plant biomass (lignocellulose) generated on marginal agricultural land will help to alleviate this competition. Eucalypts, the broadly defined taxa encompassing over 900 species of Eucalyptus, Corymbia, and Angophora are the most widely planted hardwood tree in the world, harvested mainly for timber, pulp and paper, and biomaterial products. More recently, due to their exceptional growth rate and amenability to grow under a wide range of environmental conditions, eucalypts are a leading option for the development of a sustainable lignocellulosic biofuels. However, efficient conversion of woody biomass into fermentable monomeric sugars is largely dependent on pretreatment of the cell wall, whose formation and complexity lend itself toward natural recalcitrance against its efficient deconstruction. A greater understanding of this complexity within the context of various pretreatments will allow the design of new and effective deconstruction processes for bioenergy production. In this review, we present the various pretreatment options for eucalypts, including research into understanding structure and formation of the eucalypt cell wall.

Lesser auger beetle Heterobostrychus aequalis(Coleoptera: Bostrichidae) in Australia: absent or elusive?

The lesser auger beetle, Heterobostrychus aequalis (Waterhouse), is a serious pest of seasoned hardwood timber throughout the Oriental region and several areas beyond. Some early collection records of H. aequalis from Australia in the 1950s and 1960s indicated that the insect was present in northern Queensland, but no confirmed breeding population has been found in the past few decades suggesting either that it may have not established permanently or it is difficult to detect. The ambiguity about the breeding status of the pest in Australia has caused confusion for regulating authorities needing to respond to each new post-border detection. We examined records of H. aequalis in Australian insect collections and from intensive plant pest surveillance activities in Queensland and northern Australia over the past 48 years to resolve this confusion. Until very recently, available evidence suggested that H. aequalis was not established in Australia, despite multiple introductions and apparently suitable climate and hosts. Collection records of the pest are predominantly linked to intercepted items or are recorded as of unknown origin, and no established populations have been found during many years of targeted surveillance. However, a detection of H. aequalis in suburban Cairns, north Queensland, in late 2013 and two more in mid-2015 in the same general locality do not appear to be linked to any imported material, indicating that there is at least a tenuously established local population. Investigations are underway to confirm this, but the insect is not widely established in Australia and, if present, remains elusive. Our recommended response to any future detection of H. aequalis is to fumigate or destroy the infested material, conduct tracing enquiries and limit surveys to the immediate vicinity of the detection.

An Investigation of Environmental Conditions Experienced During the Life of High Value Wood Components and Products

Australian forest industries have a long history of export trade of a wide range of products from woodchips(for paper manufacturing), sandalwood (essential oils, carving and incense) to high value musical instruments, flooring and outdoor furniture. For the high value group, fluctuating environmental conditions brought on by changes in mperature and relative humidity, can lead to performance problems due to consequential swelling, shrinkage and/or distortion of the wood elements. A survey determined the types of value-added products exported, including species and dimensions packaging used and export markets. Data loggers were installed with shipments to monitor temperature and relative humidity conditions. These data were converted to timber equilibrium moisture content values to provide an indication of the environment that the wood elements would be acclimatising to. The results of the initial survey indicated that primary high value wood export products included guitars, flooring, decking and outdoor furniture. The destination markets were mainly located in the northern hemisphere, particularly the United States of America, China, Hong Kong, Europe including the United Kingdom), Japan, Korea and the Middle East. Other regions importing Australian-made wooden articles were south-east Asia, New Zealand and South Africa. Different timber species have differing rates of swelling and shrinkage, so the types of timber were also recorded during the survey. Results from this work determined that the major species were ash-type eucalypts from south-eastern Australia (commonly referred to in the market as Tasmanian oak), jarrah from Western Australia, spotted gum, hoop pine, white cypress, black butt, brush box and Sydney blue gum from Queensland and New South Wales. The environmental conditions data indicated that microclimates in shipping containers can fluctuate extensively during shipping. Conditions at the time of manufacturing were usually between 10 and 12% equilibrium moisture content, however conditions during shipping could range from 5 (very dry) to 20% (very humid). The packaging systems incorporated were reported to be efficient at protecting the wooden articles from damage during transit. The research highlighted the potential risk for wood components to ‘move’ in response to periods of drier or more humid conditions than those at the time of manufacturing, and the importance of engineering a packaging system that can account for the environmental conditions experienced in shipping containers. Examples of potential dimensional changes in wooden components were calculated based on published unit shrinkage data for key species and the climatic data returned from the logging equipment. The information highlighted the importance of good design to account for possible timber movement during shipping. A timber movement calculator was developed to allow designers to input component species, dimensions, site of manufacture and destination, to see validate their product design. This calculator forms part of the free interactive website www.timbers.com.au.

Puukaupan säännöt : Yksityismetsänomistajien ja metsäteollisuuden puukauppa Itä-Suomessa 1919 - 1939

The Finnish forest industry bought more than half of the timber used in factories and sawmills in the 1930s from non-industrial private forests (NIPF). This research investigates the rules conformed to this timber trade. The main research questions are: what were the rules that influenced the timber trade; and by whom they were set up? Attention is also paid to the factors which advanced the forest owners’ negotiation possibilities. A variety of sources were used: legal and company statutes, timber trade contracts, archives of the forest companies and organisations. Moreover, the written reminiscences collected by the Finnish Literature Society in the early 1970s were used to analyse the views of individual sellers and buyers. An institutional economics approach was applied as the theoretical framework of this study. In the timber trade the seller (forest owner) and the buyer (the employee of the forest company) agreed to the rules of the timber trade. They agreed about the amount and the price of the timber on sale, but also rules concerning, e.g., timber marking and harvesting. The forest companies had a strong control over the written contracts. Neither the private forest owners nor the forest organisations had much influence over these contracts. However, they managed to influence the rules which could not be found in the contracts. These written and unwritten rules regulated, for instance, the timber marking and measurement. The forest organisations such as Central Forestry Board Tapio (Keskusmetsäseura Tapio) and associations of forest owners (metsänhoitoyhdistykset) helped private forest owners in gaining more control over the timber marking. In timber marking, the forest owner selected trees to be included in the timber trade and gained more information, which he could use in the negotiations. The other rule, which was changed despite forest companies’ resistance, was the timber measurement. The Central Union of Agricultural Producers (MTK) negotiated with the Central Association of Finnish Woodworking Industries (SPKL) about changing the rules of the measurement practices. Even though SPKL did not support any changes, the new timber measurement law was accepted in the year 1938. The new law also created a supervisory authority to solve possible disagreements. Despite this the forest companies were still in charge of the measurement process in most cases. The private forest owners attained changes in the rules of the timber trade mainly during the 1930s. Earlier the relative weakness of the private forest organisations had diminished their negotiation positions. This changed in the 1930s as the private forest owners and their organisations became more active. At the same time the forest industry experienced a shortage of timber, especially pulp wood, and this provided the private forest owners with more leverage. Full-text (in Finnish) available at http://helda.helsinki.fi/handle/10224/4081

Participation or further exclusion? : Contestations over forest conservation and control in the East Usambara Mountains, Tanzania

This Ph.D. thesis Participation or Further Exclusion? Contestations over Forest Conservation and Control in the East Usambara Mountains, Tanzania describes and analyses the shift in the prevailing discourse of forest and biodiversity conservation policies and strategies towards more participatory approaches in Tanzania, and the changes in the practises of resource control. I explore the scope for and limits to the different actors and groups who are considered to form the community, to participate in resource control, in a specific historical and socio-economic context. I analyse whether, how and to which extent the targets of such participatory conservation interventions have been able to affect the formal rules and practices of resource control, and explore their different responses and discursive and other strategies in relation to conservation efforts. I approach the problematic through exploring certain participatory conservation interventions and related negotiations between the local farmers, government officials and the external actors in the case of two protected forest reserves in the southern part of the East Usambaras, Tanzania. The study area belongs to the Eastern Arc Mountains that are valued globally and nationally for their high level of biodiversity and number of endemic and near endemic species. The theoretical approach draws from theorising on power, participation and conservation in anthropology of development and post-structuralist political ecology. The material was collected in three stages between 2003 and 2008 by using an ethnographic approach. I interviewed and observed the actors and their resource use and control practices at the local level, including the representatives of the villagers living close to the protected forests and the conservation agency, but also followed the selected processes and engaged with the non-local agencies involved in the conservation efforts in the East Usambaras. In addition, the more recent processes of change and the actors strategies in resource control were contextualised against the social and environmental history of the study area and the evolvement of institutions of natural resource control. My findings indicate that the discourse of participation that has emerged in global conservation policy debate within the past three decades, and is being institutionalised in the national policies in many countries, including Tanzania, has shaped the practices of forest conservation in the East Usambaras, although in a fragmented and uneven way. Instrumental interpretation of participation, in which it is to serve the goals of improving the control of the forest and making it more acceptable and efficient, has prevailed among the governmental actors and conservation organisations. Yet, there is variation between the different projects and actors promoting participatory conservation regarding the goals and means of participation, e.g. to which extent the local people are to be involved in decision-making. The actors representing communities also have their diverse agendas, understandings and experiences regarding the rationality, outcomes and benefits of being involved in forest control, making the practices of control fluid. The elements of the exclusive conservation thinking and practices co-exist with the more recent participatory processes, and continue to shape the understandings and strategies of the actors involved in resource control. The ideas and narratives of the different discourses are reproduced and selectively used by the parties involved. The idea of forest conservation is not resisted as such by most of the actors at local level, quite the opposite. However, the strict regulations and rules governing access to resources, such as valuable timber species, continue to be disputed by many. Furthermore, the history of control, such as past injustices related to conservation and unfulfilled promises, undermines the participation of certain social groups in resource control and benefit sharing. This also creates controversies in the practices of conservation, and fuels conflicts regarding the establishment of new protected areas. In spite of this, the fact that the representatives of the communities have been invited to the arenas where information is shared, and principles and conditions of forest control and benefit sharing are discussed and partly decided upon, has created expectations among the participants, and opened up opportunities for some of the local actors to enhance their own, and sometimes wider interests in relation to resource control and the related benefits. The local actors experiences of the previous government and other interventions strongly affect how they position themselves in relation to conservation interventions, and their responses and strategies. However, my findings also suggest, in a similar way to research conducted in some other protected areas, that the benefits of participation in conservation and resource control tend to accrue unevenly between different groups of local people, e.g. due to unequal access to information and differences in their initial resources and social position.