Annual Report of the Department of Forest and Wood Science

2012

Message from the chairman The Department of Forest and Wood Science (DFWS) celebrated its 80st anniversary in 2012. In 1931, Stellenbosch University was identified as an appropriate provider for this field of study, and the Faculty of Forest and Wood Science was established in 1932. Since then, the Faculty (and later Department) has awarded 890 BSc, 210 MSc, 42 PhD and 11 DSc degrees. The Department’s strategic direction remained the same as previous years and concentrated on:

Increasing international visibility Expanding focus on Africa Partnering with industry

Besides participation in three EU COST Actions, the BMBF financed SASSCAL project was successfully awarded with its focus on climate change adaptation and its outreach concept into Africa, especially the SADC region. Institutions in Botswana, Mozambique, Namibia, Zambia and Malawi form part of the consortium. Three international projects were initiated in cooperation with partners in Namibia and other SADC countries: (1) the development of an MSc course on dryland forestry with SADC partners, (2) a project participation on sustainable wood land management and (3) the optimisation of a wood conversion value chain. “Climate Change” is a strong focus of the Department, and it remains a challenge that may only be solved through inter-disciplinary and interna-tional collaboration by researchers. Several successful projects in this area are in operation, such as the “Green Landscapes” project, a prestig-ious multidisciplinary and international project on holistic landscape man-agement granted by the NRF/DST. This project is one of only three suc-cessful applications at Stellenbosch University, making us part of a grow-ing climate research movement at Stellenbosch. An EU financed Marie Curie IRSES mobility project, “Climate Fit For-ests”, gained momentum in 2012 with the first international visitors from the partner universities in Germany, Italy and Switzerland. This initiative involves a broad spectrum of climate change related research activities. Furthermore, projects dealing with wood quality, drought effects in natu-ral forests, fire response of trees, growth and wood quality of drought resistant eucalypts came to fruition during the year.

The work on conventional tree breeding continues and the DFWS is cur-rently the only South African academic research institution which is part of CAMCORE. A FESA project on the retrieval and use of forest residues for bioenergy in South Africa was compiled and the results released in 2012. The Department contributed in the development of several chapters in the new edition of the South African Forestry Handbook, which were well received by the forestry industry. The Department has always had a clear focus on plantation forestry, documented by several successful industry related projects. New re-search projects show a continuing trend in broadening this focus by in-corporating woodlands and indigenous forests into its research. Besides involvement in the SASSCAL project, the Department is working on pro-jects dealing with the carbon sequestration in the Mecrusse woodlands of Mozambique, the trade-off between carbon and timber production of Kiaat in Namibia, firewood use in the dry woodlands of Namibia, compe-tition effects in indigenous afrotemeperate forests of the Southern Cape and the regeneration biology of Wyddringtonia whitey in Malawi. Prof. Tim Rypstra retired on the 31st of December after 37 years of dedi-cated service to the University and the Department. We wish him well in his retirement. In conclusion, the Department looks forward to a productive and exciting 2013. Thomas Seifert

Academic Staff

Brand Wessels Wood Mechanics

Pierre Ackerman Forest Engineering

Cori Ham Forest Economics

Martina Meincken Wood Physics

Tim Rypstra Wood Chemistry

Thomas Seifert Forest Management

Hannél Ham Forest Development

Barend Lötter Furniture Construction

Luvuyo Tyhoda Wood Chemistry

Ben du Toit Silviculture

Academic Support

Technical and Administrative Support

Mark Februarie Technical Officer, Forest Science

Poppie Gordon Administrative Officer

Wilmour Hendrikse Technical Officer, Wood Science

Ursula Petersen Departmental Secretary

John de Wet Forest Operations

Anton Kunneke Remote Sensing, GIS

Stefan Seifert Postdoctoral Fellow Green Landscapes

Extraordinary professors William Dvorak Professor in Tree Improvement Coert Geldenhuys Professor in Forest Ecology Michael Jacobson Professor in Forest Management Reino Pulkki Professor in Forest Engineering Klaus von Gadow Professor in Forest Management Walter Warkotsch Professor in Forest Engineering

Research Visitors in 2012

The year 2012 was a year of vibrant research exchange at the Department with several international visitors and several staff mem-bers going abroad for research:

Prof Marie Johansson from Linnaeus University in Sweden visited the Department to contribute to the work on wood characterisation of drought resistant eucalypts. In turn Brand Wessels went to Linnaeus University in Växjö and Innventia, Stockholm.

Prof. Thomas Seifert visited the TU München Germany for research within the EU Marie Curie project "Climate Fit Forests" and also visit-ed Göttingen University to liaise with several colleagues to foster the collaboration between the two Departments.

Prof. Martin Ziesack from Bern University for Applied Sciences, Switzerland collaborated on the "Climate Fit Forests" project and fo-cussed on questions of reduced energy consumption in forest opera-tions.

Prof Klaus von Gadow used an extended research stay to contribute to an analysis of competition in afromontane forests.

Dr. Jakub Sandak from the Italian Tree and Timber Research Insti-tute in Italy visited us to discuss possible co-operation.

Sam Field was our annual exchange student from UBC, Vancouver, Canada and worked in the Forest Engineering field.

Lecturing support Prof Bill Dvorak (Director: Camcore) presented a short course on Tree Improvement to the 3rd year Forest Science students from 6-10 August 2012. The focus was on world trends in forestry, basic principles of tree improvement, important forest species (Eucalyptys, Pines, Teak etc.), vari-ous tree improvement case studies (worldwide), selection criteria, experi-

mental design, clonal deployment and develop-ment.

Prof. Walter Warkotsch from the TUM, Germany and Prof Reino Pulkki from the Lakehead University, Ontario. Canada lectured on timber harvest-ing and forest road network development, construction and maintenance. Roger Jackson and Bronson Gunther from Husqvarna Pietermaritzburg pre-sented the annual Chainsaw course in September.

CT Scanner

The CT scanner unit celebrated its 1st year since the launch of the facility recently. The financial summary for the 12 months since the launch shows that the unit has achieved 100.64% cost efficiency in its first year of existence! Besides financial success, the first scientific publications have ben published, including a study of the 3D imaging of the thermal dam-age in wood cell walls. The unit is also growing: Forestry internships have started success-fully, through the visiting intern Sarah Knuth (November-February) and now Vincent Young (see photo). In addition, two new NRF/DST internships have been made available and these young enthusiastic scientists will start in May. Additional scientific 3D analysis software was acquired recently - Avizo Fire - which allows more advanced material differentiation. For more information and news please have a look at our newslet-ters, at www.sun.ac.za/ctscanner or http://blogs.sun.ac.za/ctscanner/introduction/

SFSA 2012 In 2012 the SFSA organised the following events: 1st Year’s Braai Wood Chopper’s Ball Paintball Nora Tyre’s Crèche tree planting Themed/Social Braais Beer Raffles T

The 2012 SFSA commit-tee

Tree planting at the Nora Tyre’s Creche (Cloetesville). The incen-tive was to show and teach the importance of trees. We planted one tree and will be returning in 2013 to continue the work and plant more trees to continuously develop an educational coopera-tion.

The annual paintball event to getting rid of frustrations accu-mulated during the year.

One of our braais had the motto: „What I wanted to be when I was 5“. It was a great evening filled with good company, music and food.

The annual Wood Chop-per’s Ball took place at the Oude Klok. This event is the highlight of the year for staff and students.

MSc

Ackerman Simon

Atsame-Edda Angeline

Baptista Carl

Burger Burger

Crafford Phillip

Froneman Gideon

Hainduwa Feliciana

Hans Ralston

Jacobs Dani

Jooste Guilaume

Kadas Marios

Kunneke Anton

Lerm Frederick

Lindner Gerard Eckard

Moses Moses

Ndalowa Daniel

Ngcobo Ngceba

Ngozo Ndumiso Paul

Nkhuwa Boas

Phiri Darius

van der Merwe Jaco-Pierre

Wise Andre Jean

PhD

Ackerman Pierre

Chanyenga Tembo

da Costa Dean

Dovey Steven

Goncalo Ferrao

Ham Hannel

Magalhaes Tarquinio

Mapanda Enver

Odhiambo Benedict

Ombina Christian

Sentime Kasay

Wessels Coenraad

Postgraduate Students in 2012

Graduated Postgraduate Students 2012

BSc Honours

Jooste Hendri Hongwane Philip Moses Moses Heunis George

MSc

Wondifraw Daniel The effect of site and cambial age on selected an-atomical properties of mid-rotation Pinus radiata. De Beer Carien The socio-economic impact of the phasing out of planta-tions in the Western and Southern Cape region of South Africa – a case study of three plantations

PhD Du Plessis Marius A fibre optimisation index developed from a mate-rial investigation of Eucalyptus grandis for the Kraft pulping process. Dovey Steven Effects of clear felling and residue management on nutrient pools, productivity and sustainability in a clonal eucalypt stand in South Africa.

Green Landscapes – Designing Sustainable Landscapes in an African context The objective of this NRF– funded project within the programme for global Change Sustainability and Society is the development of a spatial decision support tool for optimal land-use management.

This is a multidisciplinary collaborative project, directed by Prof Thomas Seifert and hosted by the Department of Forest and Wood Science. Participating are project partners are from the

Departments of Conservation Ecology

Entomology

Soil Science

The postdoctoral research fellow Stefan Seifert spent a large part of 2012 programming the interactive model framework. Cori Ham and several MSc and PhD students from all involved Departments are establishing the ecosystem service provision models.

The Green Landscapes framework is a public domain Decision Sup-port System (DSS) to design sustainable landscapes in an African context. It will use proposed land-use changes to estimate related impacts on ecosystem services. The user can change the current land-use pattern and then restart the integrated models to predict a set of key ecosystem services for selected climatic scenarios. The predicted ecosystem services include key variables such as food production, timber production, carbon sequestration, conservation, water balance and job creation.

A subsequent evaluating model will aggregate the different model outputs to present a weighted overall score of the landscape, which allows for comparing different land-use scenarios for regional plan-ning.

Various land use in the Greytown area

Interactive map which allows a rule based and graphical change of the land use pattern.

Departmental Research Foci Scientific work at the Department of Forest and Wood Science is character-ized by a healthy blend of basic and applied research aspects. Based on this principle, the Department has defined four overarching research fields that not only reflect our vision concerning the main questions to be an-swered by Forest and Wood Science in the coming years, but also show our ability to address the value-added chain of wood, paper and biomass production from the beginning to the end. To tackle these relevant topics we joined forces within the Department to cover the necessary bandwidth of expertise and will extend our activities in the defined focal research are-as in the future. (1) Precision Forestry Precision Forestry (PF) provides for additional, adequate quality infor-mation about forests and the manufacturing of forest products. It facilitates planning and site-specific forest management activities and operations to improve wood product quality and utilisation, to reduce waste, and increase profits. PF makes use of several key technologies such as GPS/GIS/RS, dealing with automatic data capture, including locating and navigation sys-tems. Thus PF addresses both the use of geo-spatial-information to assist forest management and planning; and site-specific silvicultural operations. The need for Precision Forestry is no longer a choice but an imperative in managing forests and producing forest products. Driven by both the ever increasing scrutiny over the protection of forest resources, and the eco-nomic need to use forest products to the fullest, professional foresters and product managers are demanding quality detailed information about forests they manage and products they make. (2) Integrated Land Use Management Initiative “Green Landscapes” “Green Landscape Design” is a concept which spatially integrates different strategies and economic demands within the same region and includes all land use. In this context, it plays a cardinal role in Africa. The requirements for forest services are manifold and they are not constant over time. Tradi-tional forest planning is based on principles of constancy and long term stability. In reality, however, periodic reorientation and frequent changes of policy are quite common. It is also understood that not only one, but a vari-ety of treatment options or “management paths” may be potentially suitable for each individual land parcel. Each path is characterized by a succession of specific management activities, unexpected hazards and specific system responses.

The ultimate aim is to identify some optimum combination of management paths for the landscape as a whole. The conceptual framework for this re-search is provided by the Multiple Path Theory which assumes that a land-scape is an aggregation of spatially defined land parcels of varying size and shape. This form of adaptive management provides a suitable basis for designing forested landscapes. (3) Biomass and Biofuel Production Initiative “Power SA” The “Power SA” initiative aims at providing all necessary information on biomass and biofuel production in a South African and African context. It covers the value-added chain of production from the plant to the product of biomass and biofuels. This involves a wide range of expertise including remote sensing, inventory, resource estimation with the help of simulation models, stand management for biomass production in plantations, agro-forests, extensively managed forests, harvesting and transport, transfor-mation technology and raw material quality considerations, ecologic impli-cations on local and global level as well as socio-economic implications of bio-energy production. The Department will focus future research work on the integration of these fields of expertise for concise management of bio-mass and biofuel production. Our aim is to contribute to the optimization of resource use and the mitigation of climate change. (4) Wood Quality from the Plant to the Product Wood quality may be the most essential aspect of the value added chain of wood production, but also the one least understood. Optimisation and ef-fective management of the value added chain and its individual links is only possible with a sound knowledge of the factors influencing wood properties during tree growth, harvesting, storage, drying and multiple conversion steps; and also depends on the the quality of determination process itself. A holistic approach that attempts to link the single steps of production to understand their dependencies and identify crucial steps in the conversion chain that can be influenced by management is required. This includes modelling, simulation and novel methods of wood quality determination and product performance testing with the objective to understand and optimize wood quality throughout the value added chain of wood production.

Silv

icul

ture

Plantation Silviculture Forest eco-physiology

Forest Soils and Nutrition Tree crops for Bio-energy

Sustainability & Fire Management

Testing controlled release fertilizers (CRF's) applied to eucalypts at planting Young eucalypt stands often respond to fertilizer application during the establishment phase, yet nutrient demand increases up to canopy clo-sure (i.e. 9-18 months in most SA gum stands). Fertilizer elements in conventional fertilizer sources applied at planting may be immobilized in plant-unavailable forms or may leach out in fair quantities over time. Our aim with CRF's is thus to increase stand nutrient accretion during the prolonged supply period, so that it can build a bigger, more nutrient-rich leaf area. This will allow for ample and effective re-translocation of nutri-ents within the growing trees during the phase after canopy closure. Three CRF trials in eucalypt stands have been established in KZN dur-ing the last year (Photo's 1 and 2). The survival on all three sites are excellent, and early results show that significant height growth respons-es are being obtained with up to 40 and even 80 g of controlled release N per plant. Intensive measurements on stem growth, leaf area index and nutrient uptake continues to understand and quantify the long-term growth response.

1

2 3

Sustainable productivity of short-rotation stands During 2012, FESA commissioned a study on the use of forest residue for bio-energy. Our contribution focused on the effect of increased levels of biomass + residue harvesting on nutrient input-output budgets. The impact of various management scenario's on nutritional sustainability of pine and eucalypt plantations in the summer rainfall zone could be demonstrated (see ICFR Bulletin 03-2013). In the Western Cape, several genotypes are being tested as short-rotation eucalypt crops grown for poles and/or bio-energy (Photo 3). The water availability gradient across the sites spans the range from moist sub-humid, to semi arid and arid regions (Photo 4). The results of these trials formed the basis for two presentations by Ben du Toit and co-workers at 2 interna-tional symposia in Chilé during 2012: (a) Tree-based strategies to mitigate climate change whilst providing bio-energy, employment and ecosystem services, and (b) Expanding eucalypt plantings to dry areas of Southern Africa requires new taxa and more accurate site-taxon matching. Dendrology / Forest botany Considerable work has been devoted to update the Forest botany modules offered by the Department following the publication of new taxonomic rela-tionships by the International Angiosperm Phylogeny Group (APG III). A dedicated effort is also being made to source new samples for the Williams Herbarium at the Department and to include (and update) the most im-portant uses and wood properties of the commercially important species in the curriculum. Photo 5 shows a mixed forest of Araucaria and Nothofagus species in central Chilé

4 5

Fore

st M

anag

emen

t

Forest and Tree Growth Growth and Environment

Dendro-ecology

Carbon sequestration modelling for Mecrusse woodlands Objective is the development of biomass and carbon functions for above and belowground phytomass of Androstrachys johnsonii in Mozambique in order to estimate carbon. Irregular stand structures

Irregular stand structures can result from inadequate thinning prac-tice or natural hazards, The objectives of this project are to analyse the effects of irregular stand structures on growth, wood quality and develop mitigation options for operational harvest planning and thin-ning of Pinus patula.

Evaluation of drought resistant tree species to alleviate poverty in arid regions of South Africa The objective of this project is to determine growth, biomass and wood quality of drought resistant eucalypts in order to establish a sustainable wood source for small growers and communities in arid areas. The effect of fire damage on the growth and survival of native and commercial trees in South Africa

Objective is to analyse factors that influence the fire resistant of trees. A key element of the project is the quantification of the influence of the structural, physical and chemical properties of bark and their influence on heat resistance.

Further projects: Parameterisation and application of an individual tree hybrid growth mod-el for South African plantation stands Using spatial landscape attributes to estimate forest structure The effects of bark stripping on growth and defence reaction on native trees in South Africa Impact of drought on mortality and diameter increment in the afromon-tane forests in Southern Africa. Influence of water availability on tree ring growth, latewood proportion and wood density of Pinus radiata in South Africa Biomass modelling of three drought resistant Eucalyptus genotypes growing on west coast of South Africa

Fore

st E

ngin

eerin

g

Supply Chain Management Timber Harvesting

and Logistics

The impact of mechanical log surface damage on fibre loss and chip quality when processing Eucalyptus pulpwood using a single-grip harvester This MSc study aims to investigate the influence of different debarking techniques and tree characteristics on industrial eucalyptus wood chip production in relation to log surface damage, fibre recovery, and wood chip size distribution including any fracturing, wood chip moisture con-tent uniformity and bark content. These variables influence pulp yield and quality, in pulp manufacturing. The Maskiner SP processor head will be mechanised component used in this study, which will be located in the Zululand coastal plain of South Africa.

On-board computing in forest machinery as a tool to improve skid-ding operations in South African softwood sawtimber operations This study shows the results of a series of trials to better understand the quality of information and the application possibilities of On Board Compu-ting (OBC) systems in forest timber harvesting operations. The following objective were set for the study; 1) evaluate the accuracy of information collected using OBC systems, and 2) assess the suitability of the infor-mation to calculate productivity and other work parameter. Mechanised cut-to-length harvesting systems optimisation using Dis-crete Event Simulation An MSc project currently in progress involves productivity, cost and sys-tems analyse of mechanised cut-to-length eucalyptus pulp-wood harvester and forwarder system with Operational Research methods using discrete event simulation. Intensive and detailed time studies will be carried out on the systems in order to obtain a comprehensive dataset that will be used for the modelling. The simulation will be used to adjust harvesting opera-tions being modelled to identify possible systems improvements and com-binations of machines in the system; essentially removing delay causing factors and improving operational techniques. This study will follow on from a previous study that was conducted testing the applicability of simulating a mechanised harvesting system.

Rem

ote

Sens

ing

and

GIS

Forest Informatics Remote Sensing Spatial Analysis

Hyperspectral remote sensing project The airborne hyperspectral sensor project was extended to do close range sensing of vegetation and objects . The sensor was optically adjusted to focus at close range. This opens opportunities to use the sensor in times when the weather is not suited to aerial work. A spatial representation is produced of the variability of growth in a tree indicat-ing young and older leaves for example. Work is also planned for wood samples and other applications in 2013. Work on agricultural plots, wheat and vines were also conducted.

Costing Model A new specification was prepared for the South African Harvesting and Transport Systems Costing Model. A programmer has been tasked to write the code for the new application. The graphical interface in the new application is more user friendly and a number of previously not included features have been incorporated into the new costing model. A thorough testing of all functions and calculations is currently underway and once complete the application will be prepared for release which is expected to be around July 2013. Stereo aerial photography Work relating to aerial survey of plantations were continued this year. Both UAV and aeroplane surveys were conducted. The stereo images were used to create digital terrain models of the sampled areas, which included the FOSIM project areas managed by Prof Seifert and nutrition trails of Dr du Toit. Different software packages were tested for ease of use and quali-ty of 3 dimensional output.

Fore

st E

cono

mic

s

Enterprise Development Forestry Promotions

Rural Forest Use

Development of a dynamic decision support framework for the optimisation of financial returns from conservation areas on plan-tation forestry estates in South Africa The primary objective of the project is to develop a dynamic decision support framework that can be used to define management paths for conservation areas located on forestry estates in order to optimise fi-nancial returns from ecosystem services derived from those conserva-tion areas. Attaching real financial values to conservation areas can help to provide more objective values to these areas in plantation valu-ations and will also help to justify the costs of managing them. Sec-ondary objectives involve the development of input models for the de-cision support framework and the testing of the framework during for-estry estate valuations.

Impact of fuelwood quality and quantity on rural households’ energy use in Omusati region in North-West of Namibia This study aimed to investigate the relationship between fuel use and quality and quantity of fuel in two rural villages (Ongulumbashe and Onaitembu) in the Omusati Region of Namibia. It investigated the impact of fuel quality and quantity and the corresponding sales of firewood on households’ energy consumption. Data was collected between April and June 2012 from the two villages by means of questionnaire surveys, bio-mass assessment and laboratory assessment. Interviews were conduct-ed with seventy-seven households, four firewood sellers, government officials, and local leaders. The study quantified the amount of fuelwood consumed and collected per household per week using user-recall and physical measurement, respectively. The most preferred fuel species or fuel materials were identified and their physical properties, calorific value, moisture content, ash content and density were measured under labora-tory conditions. Assessment of trade-offs between timber and carbon values of Pter-ocarpus angolensis (Kiaat) in the Kavango Region of Namibia - a comparison of current and potential values This study’s main aim was to estimate the total value of an average Kiaat tree marked for harvesting with a focus on current timber use value, value of an optimally utilised tree, carbon value, and alternative uses of Kiaat trees. A combination of a socio-economic survey and tree volumes and biomass determination was used to collect data. The survey entailed Kiaat products assessment and face-to-face personal interviews with known key-informants in and around Rundu. Loggers with permits to harvest Kiaat trees were asked to harvest 40 Kiaat trees and allometric data were collected from each tree before and after felling.

Fore

st D

evel

opm

ent Community Forestry

Plant Propagation Tree Improvement

Forest Ecology Agroforestry

Investigating the reproductive barriers of Pinus radiata Pinus radiata is a very important species in plantation forests in South Africa due to outstanding wood quality, good commercial forestry val-ue and climatic adaptability, but is highly susceptible to Fusarium cir-cinatum. Forestry companies worldwide have tried to hybridise P. radiata with other Pinus species that have mild resistance/ tolerance to F. circinatum to overcome susceptibility, extend the geographic planting range and retain the excellent wood qualities, but there ap-pears to be reproductive barriers hampering hybridisation success. The aim of this study is to establish a new protocol for successful hy-bridisation of P. radiata with other, Fusarium-resistant pines and is in collaboration with CAMCORE.

Preliminary results on pollen grain size and pollen tube growth rate showed significant differences for all seven species under investigation. However, there is no correlation between pollen grain size and pollen tube growth rate. Various families from the Pinus radiata breeding programme of Cape Pine have been screened for Fusarium circinatum resistance. All the families showed various severe susceptibility. Rehabilitation of alien invaded riparian zones and catchments us-ing indigenous trees: an assessment of indigenous tree water use. One component of the study is done at Buffeljagsrivier, near Swellen-dam. The main focus of this project is on the dynamics of the regenera-tion of natural forest species spreading into a stand of the invasive alien tree Acacia mearnsii along the Buffeljagsrivier. A total of 340 forest spe-cies clusters establishing in the 90 ha wattle stand, with >40 forest spe-cies included, were recorded. Another component of the main project investigates the changes in biomass production and carbon sequestration potential with converting the invasive alien tree to natural forest. This complements a study on water use by Mr Bruce Scott-Shaw from UKZN. The effect of population size on viable seed output, seed rain and natural regeneration pattern of a tropical conifer Widdringtonia whytei in Malawi is under investigation. This endemic fire-adapted pioneer tree species occurs in fragmented forest patches on Mulanje Mountain in Malawi and is related to the South African Cedarberg cedar W. cedarbergensis and Baviaanskloof cedar W. schwarzii. The results highlighted some of the difficulties the species is experiencing in terms of viable seed production, seed dispersal and seedling regeneration in and around the forest patch-es. It provided important information for the conservation and manage-ment of this important high value conifer.

Woo

d P

roce

ssin

g

Non destructive Timber Testing Prediction of Timber Quality

Sawmill Processing

The flexural properties of young SA Pine The roof truss industry is arguably the single most important market for our sawmilling industry. The main objective of this study was to determine the most critical design property in typical South African roof truss designs and to determine the relative utilization of the diffe-rent characteristic strength and stiffness values in typical roof truss designs. Thirty truss designs consisting of 8758 individual members from 3 different manufacturers were analysed using the Mitek Timber 2020 software suite. Of all the individual strength properties, bending strength was the most influential in truss design. Local deflection, which is related to the stiffness or MOE of timber, was also found to be influential in truss design.

A method for three-dimensional stem analysis Information on the external shape and internal properties of a tree such as the branch structure, tree ring widths and defects such as resin pockets is important for many forest –and wood science rese-archers. An in field system for stem dissection which were used to develop three-dimensional models of logs and trees including some macroscopic internal characteristics were designed and built

A study on the occurrence of resin pockets in Pinus patula A study was conducted on the occurrence and causes of resin pockets in Pinus patula from the Mpumalanga escarpment, South Africa. Twenty-four trees from three compartments were dissected and then digitally re-constructed into three-dimensional models. A total of 61 cuts with resin pockets were identified in the roughly 2750 cross cut images obtained. The formation of Type 2 resin pockets was most probably due to felling damage during thinning operations. It seems likely that wind damage and possibly insect attacks might be responsible for the formation of Type 1 resin pockets in Pinus patula. An investigation of selected mechanical and physical properties of young, unseasoned and finger-jointed Eucalyptus grandis timber In this study the concept of using young finger-jointed Eucalyptus grandis timber was evaluated for possible application in roof truss structures while the timber is still in the green, unseasoned state. The objectives of this study were to determine various mechanical and physical properties of this finger-jointed product. More specifically (1) to determine the strength and stiffness potential of the product in the wet and the dry con-dition, (2) to evaluate physical properties such as density, warp, checking and splitting, (3) to evaluate potential indicator properties to be used as structural grading parameters, and (4) to compare the flexural properties to the current SA pine resource and SANS structural grade requirements. Prediction of selected mechanical product properties from standing trees Various methods to determine structural timber quality of standing trees are evaluated in this project. Acoustic methods, branch and knot evaluati-on methods, and wood quality tests on increment cores are evaluated. Repeatability of the method, age-age correlations, and the relationship between standing tree acoustic wave speed and final product properties.

Woo

d Ph

ysic

s Surface Analysis Composite Materials

Bio-energy

Thermally degraded wood Several projects in 2012 dealt with the quality of wood that has been exposed to wildfires trying to answer the question if, and to what degree this wood is still usable. One project determined if the exposure to a flame leads to the same responses in wood as exposure to heat, as a flame in-volves a chemical oxygenation reaction. Another project determined the exact onset of degradation with regards to density and mechanical properties. Small wood samples were exposed to various temperatures and their struc-tural change studied with CT scanning. A last, ongoing project, tries to classify damage caused by fire on the tree as well as in the wood. As it is commonly not known to what temperature the wood was exposed during a fire, the first step of this classification is visually on the tree.

More detailed analysis on the physical, chemical and anatomical wood quality is performed on wood samples sourced from the dif-ferent classes to obtain a clear indication which wood is still useful for a certain purpose. The effect of climate change on wood quality This project determined how wood and fibre quality of Pine and Eucalypt species are effected by different water availability to al-low us to create a model to predict wood quality with a changing climate. In 2012 we determined sites and collected samples from E. cladocalyx, that are currently analysed for anatomical proper-ties. The biggest challenge was the sample preparation of the very hard wood, in order to be able to see tree-rings and cell structures. Bioenergy Together with various industries we are working on a database of physical and chemical properties of biomass suitable for energy conversion, including commercial and invasive species

Woo

d C

hem

istry

Wood Degradation & Preservation Chemical Utilization of Wood

Pulp & Paper

The PAMSA funded project “Biorefinery Concepts for Wood Pro-cessing in the South African Pulp and Paper industry” can be divided in three sub-projects: 1. Targeted modification and application of hemicelluloses to diver-sify functional properties of cellulose based products for novel appli-cation 2. Conversion of E. grandis biomass residues into valuable bio-energy products through thermo-chemical processing (pyrolysis). 3. Energy products from pulp mill sludge. 4. Characterization of lignin carbohydrate complexes

The project focuses on the development of technologies and processes for integration into a biorefinery for the production of a range of valuable products from wood-based raw materials from the forestry sector in South Africa. The project in particular, focuses on the development of novel processing technologies to produce speciality hemicelluloses bi-opolymers, novel cellulosic products and renewable energy from Euca-lyptus grandis. E. grandis is by volume the major wood-based raw mate-rial processed by the local industry, although current processes focus exclusively on pulp production. Improved and alternative methods of pro-cessing for E. grandis were investigated, including isolation, fractionation and modification of hemicelluloses, pulp fibres (cellulose), and lignin. Production of multiple, value added products from E. grandis will provide the pulp and paper industry with opportunities to diversify its business for improved economic viability. The ultimate goal was to develop technolo-gies that will allow the pulp and paper industry to produce new products in the form of speciality organic polymers, cellulosic products with new functional properties for specialized industrial applications, and to utilise part of the feedstock for the production of biofuels. These products all represent significant potential for new commercial value to the industry. Process development will include the use of advanced analytical tools to elucidate and monitor changes in the chemical and physical characteris-tics of hemicelluloses, cellulose, and lignin during processing of E. gran-dis, and conditions for selective isolation, fractionation, modification and/or thermo-chemical conversion (pyrolysis) of the raw material, hemicellu-loses, cellulose and lignin for value addition.

Funding and Sponsors The department is very grateful for financial support from: Alternative Structures, SA Camcore Cape Pine Cape Timbers DAFF Department for Public Enterprises Diggersrest Farmsecure Agri Science FESA Hans Merensky KLF Mondi NCT NRF Sawmilling SA Rance Timbers Sappi SIDA Terason Thrip York Timbers

Collaborations

Prof Colin Dyer, Steven Dovey (ICFR) Drs Dirk Laengin, Marius du Plessis and Dean da Costa (Mondi) Stellenbosch University: Botany, Plant Pathology, Horticulture, Poly-

mer Science, Soil Science, Agricultural Economics Sustainability Institute Prof Bart Muys (KU Leuven, Belgium) Dr A de Jong (Uni of Wagenenin Holland) Profs. T Anfodillo and R Cavalli, Drs. M Carrer and M Pellegrini

(Padua University, Italy) Prof. H Pretzsch, Prof. T Knoke (TUMünchen, Germany) Profs. H Militz, C Kleinn (Georg August Univ. Göttingen, Germany) Veronika Cottontail (University Ulm, Germany) Prof. M Ziesak (University of Applied Sciemce Bern, Switzerland) John Lyons, Coillte Forest (Coillte, Ireland) Profs. P Geladi and T Nordfjell (SLU, Sweden) Dr L Eliasson (Skogforsk, Sweden) Prof. M Johansson (Linnaeus University, Sweden) Prof. O Lindgren (LTU, Sweden) Sven Olof Lundqvist (Innventia, Sweden) Drs. B Talbot and H Belbo (Sogoglandskap, Norway) Prof Bo Dahlin (University of Helsinki, Finland) Prof. Rafael Rubilar (Univ. of Concepcion, Chilé) Drs. S Barros and V Emhart Schmidt (Instituto Forestral, Santiago,

Chile) Dr Claudio Balocchi (Arauco, Chile) Dr Raul Schenone (Forestal B. del Plata, Argentina) Prof Damase Khasa (Laval University, Quebec. Canada) Mark Brown (University of the Sunshine Coast, Australia)

ARC, Germplasm Development Division and Infruitec DAFF Forest Engineering, Smurfit Kappa (Colombia) FESA MPAC Tree Improvement Division , Mondi Tree Improvement Division , Sappi Tree Improvement Division , Cape Pine Tree Improvement, Forestry Department, Camcore (USA) Tree Improvement Division , Hans Merensky Tree Improvement Division , PG Bison Tree Improvement Division , York Timbers Tree Improvement Division , KLF

Peer-reviewed Journal Publications

ACKERMAN PA, PULKKI RE. Fibre volume losses of eight softwood clear-fell harvesting systems in South Africa. Southern Forests 2012; 74(2): 133-149. ALAM MB, PULKKI RE, SHAHI C, UPADHYAY T. Modelling Woody Bio-mass Procurement for Bioenergy Production at the Atikokan Generating Station in Northwestern Ontario, Canada. Energies 2012; 5: 5065-5085. CHANYENGA TF, GELDENHUYS CJ, SILESHI GW. Germination response and viability of an endangered tropical conifer Widdringtonia whytei seeds to temperature and light. South African Journal of Botany 2012; 81 : 25-28. MALA WA, GELDENHUYS CJ, PRABHU R. Perceptions of Climate Varia-bility and Pest-Disease Incidence on Crops and Adaptive Forest-Agricultural Practices. Culture and agriculture 2012; 34(1): 53-67. MEINCKEN M. Powering Africa. South African Journal of Science 2012; 108(1062): 1-2. PRETZSCH H, DIELER J, SEIFERT T, RÖTZER T. Climate effects on productivity and resouce-use efficiency of Norway spruce (Picea abies) [L.] Karst.) and European beech (Fagus sylvatica [L.] in stands with different spatial mixing patterns. Trees-Structure and Function 2012; 26(4): 1343-1360. SCHAAF W, ELMER M, FISCHER A, GERWIN W, PRETZSCH H, SEI-FERT S, WINTER S, ZAPLATA M.K.. Monitoring the formation of struc-tures and patterns during initial development of an artificial catchment. Environmental Monitoring and Assessment 2012; published online. SHEBANI AN, VAN REENEN AJ, MEINCKEN M. Using extractive-free wood as a reinforcement in wood-LLDPE composites. Journal of Reinforced Plastics and Composites 2012; 31(4): 225-232. SMIT HC, MEINCKEN M. Time/temperature combustion profiles of vari-ous wood-based biofuels. Biomass & Bioenergy 2012; 39: 317-323. VERMEULEN WJ, GELDENHUYS CJ, ESLER KJ. Response of Ocotea bul-lata, Curtisia dentata and Rapanea melanophloeos to medicinal bark strip-ping in the southern Cape, South Africa: implications for sustainable use. Southern Forests 2012; 3(74): 183-193.

ACKERMAN PA, LÄNGIN DW, OLSEN G. Timber harvesting and transport. In South African Forestry Handbook, Southern African Institute for forestry (SAIF), Menlo Park, South Africa, 2012: 353-367. ACKERMAN PA, WARKOTSCH PW, WISE AJ. Forest Roads. In South African Forestry Handbook, Southern African Institute for Forestry (SAIF), Menlo Park, South Africa, 2012: 417-438.

Other Publications

BREDENKAMP BV. The volume and mass of logs and standing trees. In South African Forestry Handbook 2012: 239-258. DU TOIT B, NORRIS C. Elements of silviculture systems and regimes used in Southern African plantations. In South African Forestry Handbook 2012: 21-25. DU TOIT B. Matching site, species and Silviculture regime to optimise the productivity of commercial softwood species in Southern Africa. In South African Forestry Handbook, 2012: 43-49 GELDENHUYS CJ, BEZUIDENHOUT L. Rehabilitation of natural forests using nurse stands of plantation or invasive introduced species as allies. In South African Forestry Handbook, 2012: 579-598. GELDENHUYS CJ, VERMEULEN WJ. Yield regulation and silvicultural sys-tems for harvesting timber and wood products from natural forest and woodland. In South African Forestry Handbook, 2012: 545-542. GELDENHUYS CJ. Natural forests and woodlands in South Africa: Their classification and distribution. In South African Forestry Handbook, 2012: 531-543. GELDENHUYS CJ, BEZUIDENHOUT L. Rehabilitation of natural forests using nurse stands of plantation or invasive introduced species as allies. In South African Forestry Handbook, 2012: 579-598. GAYLER S, PRIESACK E, FLEISCHMANN F, HELLER W, RÖTZER T, SEIFERT T, MATYSSEK R. Modelling the Defensive Potential of Plants. In Growth and Defence in Plants, Springer, London, United Kingdom, 2012: 375-399. HAM C, UYS HJE, DAUGHERTY A. Principles of Forest Valuations. In South African Forestry Handbook, 2012: 501-509. HAM C, JACOBSON MG. Financial Decision Making in Forestry Projects. In South African Forestry Handbook, 2012: 491-500 HOGG GA, KRIEG B, ACKERMAN PA, LÄNGIN DW. Harvesting Systems and Equipment Costing. In South African Forestry Handbook, 2012: 375-384. JACOBSON MG. Role of Extension in Forestry. In South African Forestry Handbook, 2012: 511-516 KOTZE H, DU TOIT B. Silviculture of industrial pine plantations in South-ern Africa. In South African Forestry Handbook 2012: 123-140. LEUCHNER M, HERTEL C, RÖTZER T, SEIFERT T, WEIGT R, WERNER H, MENZEL A. Solar Radiation as a Driver for Growth and Competition in Forest Stands. In Growth and Defence in Plants, Springer, London, United Kingdom, 2012: 175-191. MAREE B, KOTZE H, DU TOIT B. Silviculture of industrial Eucalyptus and Acacia plantations in South Africa, 2012: 141-155.

Conference Proceedings

MAREE B, KOTZE H, DU TOIT B. Silviculture of industrial Eucalyptus and Acacia plantations in South Africa. In South African Forestry Handbook, Southern African Institute for Forestry (SAIF), Menlopark, South Africa, 2012: 141-155. PRIESACK E, GAYLER S, RÖTZER T, SEIFERT T, PRETZSCH H. Mecha-nistic Modelling of Soil-Plant-Atmosphere Systems. In Growth and Defence in Plants, Springer, London, United Kingdom, 2012: 335-353. RÖTZER T, SEIFERT T, GAYLER S, PRIESACK E, PRETZSCH H. Effects of Stress and Defence Allocation on Tree Growth: Simulation Results at the Individual and Stand Level. In Growth and Defence in Plants, Springer, London, United Kingdom, 2012: 401-432. VIERO P W M, DU TOIT B. Establishment and regeneration of Eucalypt, pine and wattle stands. In South African Forestry Handbook, Southern Afri-can Institute for Forestry (SAIF), Scottsville, South Africa, 2012: 99-106. VERMEULEN WJ, GELDENHUYS CJ, ESLER KJ. Development and imple-mentation of harvest systems for little-known species, particularly for non-timber forest products. In South African Forestry Handbook, Southern Afri-can Institute for Forestry (SAIF), Menlo Park, South Africa, 2012: 563-577. JOOSTE GHC. Management and research on Afromontane and Afrotem-perate forests in South Africa. Proceedings of the 2nd International DAAD Workshop, Ascot Conference Center, Pietermaritzburg, South Africa, Cu-villier Verlag Göttingen (Internationaler wissenschaftlicher Fachverlag) 2012: 151-155. ODHIAMBO BO, SEIFERT T. The insulation capacity of tree bark against fire damage in the Western Cape Region, South Africa. Proceedings of the 2nd International DAAD Workshop, Ascot Conference Center, Pietermaritz-burg, South Africa, Cuvillier Verlag Göttingen (Internationaler wissen-schaftlecher Fachverlag) 2012: 167-172 ROUX J-L, HANS RR. A Review of South African Forest Policy: Gearing Up for Climate Change. Proceedings of the 2nd International DAAD Workshop, Ascot Conference Center, Pietermaritzburg, South Africa, Cuvillier Verlag Göttingen (Internationaler wissenschaftlicher Fachverlag) 2012: 67-77. SEIFERT T, HAM C, DU TOIT B. Forestry and Forestry Research in South Africa. Proceedings of the 2nd International DAAD Workshop, Ascot Confer-ence Center, Pietermaritzburg, South Africa, Cuvillierr Verlag Göttingen (Internationaler wissenschaftlicher Fachverlag) 2012: 3-12. WESSELS CB, DU PLESSIS JDV, VAN ZYL F, VAN DYK L. Log Position-ing Optimisation during Primary Breakdown Sawing. 2012 Conference Divi-sion 5 Forest Products (IUFRO), Estoril Congress Centre, Lisbon, Portugal, grupo Portucel Soporcel 2012: 95-96.

Service on boards and committees, memberships Ackerman, Pierre Chairman of the Precision Forestry Research Group Coordinator of the international Precision Forestry steering committee and

initiative Member of the International Forest Engineering Conference Steering and

Research Committee. Member of the South African Institute of Forestry Member of the editorial board of the Croatian Journal of Forestry du Toit, Ben Council member of Southern African Institute of Forestry Deputy co-ordinator of IUFRO Division 1.02.05 (Silviculture and manage-

ment in arid and semi-arid regions) Member of Paarl Mountain Advisory Board Editorial board member of Forest Ecology and Management Sub-editor: Silviculture for the 5th edition of the SA Forestry Handbook

Ham, Cori Member of Southern African Institute of Forestry Member of African Forest Forum Member of the Wood Foundation Ham, Hannel Chair SAIF Western Cape Member of the South African Council for Natural Scientific Professions Member of the Southern Africa Institute for Forestry Member of the South African Society for Plant Breeders Member of the Global Partnership Initiative for Plant Breeding Capacity

Building Member of the COST FP0905 Management – (Biosafety of Forest Trans-

genic Trees) Martina Meincken Member of the SABS subcommittee on solid biofuels Member of SAIF Member of the Microscopic Society of Southern Africa Member of the Society of Wood Science and Technology

Rypstra, Tim Member of the International Research Group on Wood Preservation Member of the Oil and Colour Chemists' Association) Member of the SA Wood Preservers Association Member of the SA Pest Control Association Member of the Technical Association of Pulp & Paper Industries of SA Member of the South African Chemical Institute Member of the SABS Technical committee Seifert, Thomas Chairperson of the Department of Forest and Wood Science Deputy coordinator of the IUFRO unit 4.04.04 – Sustainable forest man-

agement scheduling. Subject editor for “Wood Science and Wood Products” at the European

Journal of Forest Research Editorial board member of the Journal for Mathematical and Computation-

al Forestry & Natural-Resource Sciences (MCFNS) Editorial board member of Southern Forests Reviewer for the NRF Editor Bioenergy for Springer book “Bioenergy from Wood: Sustainable

Production in the Tropics” in Managing Forest Eco-systems Series Board member of the Advisory Board of the School of Natural Resource

Management, NMMU George/Saasveld Board member of the Central Analytical Facilities, Stellenbosch University Tyhoda Luvuyo THRIP project assessment committee Vice Chair (SAIF) Western Cape Branch Member of the Technical Association of Pulp and Paper in Southern Africa

(TAPPSA) Member of the South African Wood Preservers Association (SAWPA). Wessels, Brand Member of the South African Institute of Forestry

Layout & edition: Martina Meincken Graphics: Di Johnson-Ackerman