RIRDC Completed Projects in 1999-2000 & Research in Progress as at June 2000

Sub-Program 2.2   Agroforestry and Farm Forestry

COMPLETED PROJECTS
PROJECT No	PROJECT TITLE	RESEARCHER	PHONE	ORGANISATION	PAGE No

Targeted Strategies for Implementation of Farm Forestry

ANU-38A	ANU Forestry Market Report	Dr UN Bhati	02 6249 3220	Australian National University
ECU-2A	Developing effective and efficient extension and advisory strategies for agroforestry	Prof. Alan Black	08 9400 5844	Edith Cowan University
ECU-3A	Practical farm forestry: whole farm case studies	Prof. Alan Black	08 9400 5844	Edith Cowan University
PN99.2102	Developing policies to encourage small- scale forestry	Dr John Herbohn	07 4781 4250	James Cook University

Sustainable Use of Natural Resources

CPF- 3A	Assessing the risk of genetic pollution from farm forestry using eucalypt species and hybrids	Dr Bradley Potts	03 6226 2604	University of Tasmania
CSF-53A	Sustaining the productivity of trees crops on agricultural land in south- western Australia	Dr Tim Grove and  Dr Tony O’Connell	08 9333 6000	CSIRO Forestry and Forest Products
CSM- 4A	Agroforestry design guidelines to balance catchment health with primary production	Dr Richard Stirzaker and  Dr Rob Vertessy	02 6246 5570	CSIRO Land and Water
DAN- 126A	Establishment of trees on non-arable land to replace weeds	Dr MH Campbell	02 6391 3828	NSW Agriculture

Optimised Productivity of Crops and Pastures

DAV-69A	Shelterbelts and crop production in north east Victoria	Dr Michael Crawford	02 6030 4500	Agriculture Victoria
DAW-70A	Blue gum timberbelt design for alley farming	Dr Tony Albertsen	08 9780 6289	Agriculture Western Australia

Optimised Direct Returns from Tree Products

CAL-4A	Development of a Farm Forestry Site Selection Manual	Dr Richard Harper	08 9334 0306	Department of Conservation and Land Management
CSE-78A	Identification of pest resistant eucalypts using near- infra red spectroscopy	Dr Rob Floyd	02 6246 4089	CSIRO Entomology
CSF-57A	Conifers in the dry country	Mr David Spencer	02 6281 8211	CSIRO Forestry and Forest Products
DAV-129A	Forecasting tree growth and yield and financial returns of key agroforestry species across Southern Australia	Dr Tom Baker and  Mr Peter Bulman	03 9450 8687 or 08 8539 2117	Centre for Forest Tree Technology or Primary Industries and Resources of South Australia
DCL-3A	Potential production of tannin and fuelwood from plantation grown bipinnate acacias	Dr Liz Barbour	08 9334 0302	Department of Conservation and Land Management
OIL-3A	Integrated mallee processing for carbon products, eucalyptus oil and electricity	Mr Colin Stucley	03 9888 6711	Enecon Pty, Ltd

Cost Effective Multi-Purpose Agroforestry Systems

CAL-2A	Adapting computer software to evaluate the visual impact of farm forestry layouts	Dr Grant Revell	08 9380 1555	The University of Western Australia
GAN-1A	Thinning native regrowth for timber production and improved biodiversity	Dr Jeanette Murray and  Mr David Thompson	02 6772 3248	Greening Australia
UWA-36A	Alley farming for improved water management and nutrient cycling in sandplain cropping	Dr Ted Lefroy	08 9380 4561	University of Western Australia
UWA-53A	Fodder species- commercial and environmental options	Dr Ted Lefroy	08 9380 4561	University of Western Australia
AGT-6A	Neem Consultancy	Dr Peter Chudleigh	07 3870 9564	Agtrans Research

Targeted Strategies for Implementation of Farm Forestry
 

Project Title	ANU Forestry Market Report
RIRDC Project No.:	ANU-38A
Researcher:	U.N. Bhati
Organisation:	Department of Forestry  Australian National University Canberra ACT 0200
Phone:	02 6249 3220
Fax:	02 6249 0746
Email:	un.bhati@anu.edu.au
Internet:	www.anu.edu.au/Forestry/info/marketreport/index.html
Objective	To prepare and disseminate nationally a quarterly market report on forest products and inputs for Australian forest growers, with a primary focus on small scale growers.
Background	Native forests and planted trees on farms have the potential to increase both wood and agricultural production and to provide a variety of environmental benefits. However, the lack of reliable and readily available market information is a major impediment to the full development of farm forestry in Australia. To address the impediment, ANU Forestry held consultations with Australian Forest Growers and others. Following their endorsement, the project commenced in June 1997.
Research	Since its commencements, the project has produced a total of 11 reports. Of the 11 reports, three were produced in the first nine months of 1999–2000.  Besides dealing with a range of important farm forestry market issues, the reports also provide actual stumpage prices received by small scale growers in various regions of Australia. The project disseminates the reports through industry newsletters and magazines, the internet, and presentations at national, regional and local meetings, workshops and conferences.
Outcomes	Feedback from readers of the reports shows that the project is providing an impartial and useful market information. The project is thus contributing towards creating more informed forest product and input markets in Australia for small scale growers.
Implications	While the project is helping to create more informed markets, the feedback also shows that market information needs of farm forest growers are vast and changing. The implication is that this important work is far from finished.
Publications	Titles of the three reports produced in the first nine months of 1999–2000 are: Trends in sawnwood market, September 1999; Market for forest products in South Korea, December 1999; and Market Trends in the 1990s, March 2000. They were published in industry outlets such as: Agroforestry News, Australian Forest Grower, NAFI News, Australian Farm Journal, Shaping the Future with Farm Forestry (The JVAP Newsletter), and Branching Out!. The reports are also published on the internet web sites of ANU Forestry, Farmwide, and others.


 

Project Title	Developing effective and efficient extension and advisory strategies for agroforestry
RIRDC Project No.:	ECU-2A
Researcher:	Prof. Alan Black
Organisation:	Centre for Social Research Edith Cowan University JOONDALUP WA 6027
Phone:	08 9400 5844
Fax:	08 9400 5866
Email:	a.black@ecu.edu.au
Internet:	www.ecu.edu.au
Objectives	§ To produce a comprehensive inventory and assessment of current extension and communication systems for agroforestry in each State of Australia. § To identify those systems and activities that are perceived by the various stakeholders to have been most successful in fostering the development of agroforestry, and to analyse their strengths, limitations, potential for improvement and potential for wider application. § To recommend information exchange and advisory strategies that can most effectively and efficiently assist agroforestry to become more widely adopted, profitable and sustainable. § To publicise the findings and recommendations among policy makers, extension and advisory staff, education providers and other stakeholders.
Background	Despite the potential benefits of agroforestry and the emergence of several Commonwealth and State tree planting programs during the 1990s, the uptake of agroforestry in Australia has been much slower than would be required if the commercial and conservation benefits are to be optimised.
Research	The research involved a study of relevant literature, as well as interviews and focus group discussions with stakeholders or potential stakeholders in farm forestry.
Outcomes	Chapter 1 of the final report examines literature on possible reasons for the non-adoption of innovative agricultural technologies or integrated management practices such as agroforestry. Chapter 2 reviews general models of agricultural extension under four main headings: linear ‘top-down’ transfer of technology; participatory ‘bottom-up’ approaches (also termed ‘group empowerment’); one-to-one advice or information exchange; and formal or structured education and training. Attention is then given to the effectiveness of various media and methods, including the present and potential use of new information technology, particularly the Internet, as a medium for extension. This is followed by an examination of criteria to be used in evaluating extension and advisory strategies for agroforestry. Chapter 3 reviews the agroforestry extension approaches that have been developed by government agencies and other organisations throughout Australia. As far as possible, the goals and vision of each agency’s various extension strategies are identified. The extension models in use are discussed in relation to the models outlined in Chapter 2. Where information is available, salient points from stakeholder perceptions of the outcomes of these strategies are reported. The degree of coordination between agencies is also examined. Chapter 4 summarises the conclusions of the study and makes recommendations. These recommendations deal with general principles that should apply throughout Australia. Where appropriate, the accompanying text provides evidence or examples from around Australia. The more detailed evidence for these recommendations is contained in earlier chapters of the report.

Implications	No one model of extension is adequate by itself. The strengths and limitations of various approaches should be borne in mind in planning and evaluating extension and advisory programs.
Publications	Extension and advisory strategies for agroforestry (RIRDC)


 
 

Project Title	Practical farm forestry: whole farm case studies
RIRDC Project No.:	ECU-3A
Researcher:	Prof. Alan Black
Organisation:	Centre for Social Research, Edith Cowan University JOONDALUP WA 6027
Phone:	08 9400 5844
Fax:	08 9400 5866
Email:	a.black@ecu.edu.au
Internet:	www.ecu.edu.au
Objective	To evaluate and document the economic, environmental and social impacts of the adoption of farm forestry on ten case study farms across Australia.
Background	The potential benefits of farm forestry are as varied as the ways in which it is practised. However, attempts to measure and document the benefits (and costs) of implementing farm forestry at the whole farm level are relatively rare. This information is useful to farmers, extension staff and policy makers as a means of reducing the economic uncertainties associated with what can be a significant long term investment for the farm business.
Research	There were three major stages to the research. Firstly, the case study sites were selected with a view to providing a diverse range of systems, rainfalls, species and finance arrangements. The second stage of each evaluation was a visit to each site to collect all available data and conduct interviews with the landholders. The final stage involved economic modelling of each project and the preparation of a report with the results of these analyses and descriptions of the project and the landholder’s account of environmental and social impacts. The financial modelling used a purpose-built financial evaluation model to provide a whole farm discounted cashflow analysis over the project cycle.
Outcomes	All of the case study farmers considered the long-term viability (both economic and environmental) of their farming businesses to be the key motivating force to adopting farm forestry. In most of the case study properties, trees were actively employed to address economic and environmental issues simultaneously. The degree to which these individual objectives for the planting were important often dictated the layout and species selection for the project. The results of the financial modelling show that 8 of the 10 farms can expect direct positive returns of varying significance to accrue from the farm forestry enterprise. The two cases where the forestry projects yielded negative results both suffered from an inability of the trees to generate a large enough income at the end of the rotation to compensate for the loss of agricultural income over the length of the rotation. Environmental impacts of the trees included: increased groundwater use; soil stabilization through root systems; provision of stock shelter; provision of habitat for birds, beneficial insects and other animals; and aesthetic benefits. For all case study properties, there was a positive social impact at the personal and family level. The most common community level impact came through increased involvement with the community, but in several instances farm forestry was producing a demonstrable positive economic flow-on effect to the community as well.
Implications	The farm forestry industry is dynamic, keen to promote its work and objectives, and receptive to any information that will help it make management decisions. Results of the modelling work indicate that there are profitable farm forestry systems for a wide range of farming systems and rainfalls. At a broader level market information and development is necessary to reduce uncertainty. At the farm level, it is important that skilled analysis and land use planning are used to effectively match land capability and land use to avoid additional high costs to the project though foregone agricultural income on land occupied by trees.
Publications	Practical farm forestry: whole farm case studies (RIRDC). RIRDC publication number R99/099


 

Project Title	Developing policies to encourage small scale forestry
RIRDC Project No.:	PN99.2012
Start Date:	October 1999
Finish Date:	June 2000
Researcher:	John Herbohn
Organisation:	James Cook University Townsville, Qld, 4811
Phone:	07 4781 4250
Fax:	07 4781 4019
Email:
Objective	To publish the proceedings from an international symposium dealing with policy measures to encourage small scale forestry.
Outcomes	The JVAP sponsored an international conference examining the issues associated with, "Developing policies to encourage small scale farm forestry". The conference report and papers are available at the web site, www.jcu.edu.au/school/cea/crc/trem.

This project was supported by the Natural Heritage Trust

Sustainable use of natural resources
 

Project Title	Assessing the risk of genetic pollution from farm forestry using eucalypt species and hybrids
RIRDC Project No.:	CPF-3A
Researcher:	Dr Bradley Potts
Organisation:	School of Plant Sciences  University of Tasmania GPO Box 252-55 Hobart TAS 7001
Phone:	03 6226 2604
Fax:	03 6226 2698
Email:	B.M.Potts@utas.edu.au
Objective	Review the risks of genetic pollution from farm forestry plantings of eucalypt species and hybrids and develop a framework for risk management.
Background	Plant invasions arising from agricultural, forestry and other activities are becoming of increasing concern worldwide and in the last decade this has focused on genetic invasion by pollen dispersal and hybridisation. In the case of eucalypts, the contamination of local, native gene pools via exotic pollen is of relevance as:  (i) pollen dispersal is much more widespread than seed dispersal;  (ii) reproductive barriers are often weak between closely related species;  (iii) European settlement has already had a major impact on Australia’s eucalypt woodlands and mallee;  (iv) there has been a rapid expansion of eucalypt plantations and restoration plantings in Australia; and (v) Australia is the custodian of an internationally important genetic resource.
Research	Review the risks of genetic pollution of native eucalypt gene pools.
Outcomes	A report on the risks of genetic pollution associated with the use of exotic species and provenances, selected material, hybrids and genetically modified plants are identified along with potential impacts on other components of biodiversity was produced. This information is used to develop a framework for risk assessment and management.
Implications	1. Gene pool management strategies should be developed for the major plantation species in Australia. 2. The risk and impacts of genetic pollution or other effects on local biodiversity should be considered as part of environmental impact assessments of eucalypt plantations and farm forestry. 3. Even where the risk or impact of genetic pollution is assessed to be high, many opportunities have been identified to minimise this risk.
Publications	Potts, B.M., Barbour, R. and Hingston, A. (2000). Assessing the risk of genetic pollution from farm forestry using eucalypt species and hybrids. A report for Rural Industries Research and Development, Joint Venture Agroforestry Program


 
 

Project Title	Sustaining the productivity of tree6 crops on agricultural land in south-western Australia
RIRDC Project No.:	CSF – 53A
Researcher:	Dr Tim Grove and Dr Tony O’Connell
Organisation:	CSIRO Forestry and Forest Products PO Box 5 Wembley WA 6913
Phone:	08 9333 6000
Fax:	08 9387 8991
Email:	t.grove@ccmar.csiro.au or t.oconnell@ccmar.csiro.au
Objectives	§ To investigate and quantify changes to fertility of soils on farmland planted to eucalypts. § To evaluate strategies to maintain soil fertility and sustain long-term high productivity of trees planted on farmland. § To relate measures of nutrient uptake and nutritional constraints to growth to measures of soil nutrient supply.
Background	Plantations of Eucalyptus globulus currently occupy about 150,000 ha of land in south western Australia. Most of the area planted is on farmland where soil fertility has been improved by annual application of P fertilizers and nutrient-rich residues from legume pastures. Agricultural experience has shown that continuous cropping or reduces fertilizer application can lead to a decline in crop yields. Conversion of agricultural land to eucalypt plantations results in reduced input of fertilisers and changes to the quantity and quality of organic residues to soil. It is important therefore to investigate the impact this change in land use will have on soil fertility and the productivity of later rotations. This project has examined the changes to soil chemical properties under plantations relative to soil under pasture, and evaluated site management options to maintain soil fertility.
Research	The approach used was to measure changes to properties of surface soils, particularly to forms and flux rates of carbon (C), nitrogen (N) and phosphorous P) within two experimental frameworks -  § paired pasture- plantation sites: properties of surface soils under later- age eucalypt stands were compared to those under adjacent pasture land at up to 31 sites throughout south-western Australia: pasture and plantation areas had a common land use history prior to the planting of trees § designed experiments on inter-rotation site management at two sites: the impact of tree harvest residue treatments (residues burnt or residues removed, retained or increased) on soil fertility is being evaluated; N mineralization rates have been measured every 4 weeks and other properties measured in soils sampled annually over 4 years from the time treatments were established.
Outcomes	Conversion of land from traditional farming systems to continuous tree cropping has resulted in lower concentrations of some forms of N and P in surface soils. Concentrations of exchangeable calcium were also lower, but exchangeable magnesium and potassium higher, in plantation soils than pasture soils. Factors contributing to these changes are reduced input of fertilisers to plantation soils, transformations in soil that render nutrients less available to plants with time, and differences in the nature of organic matter residues. While changes to some properties have appeared across the range of sites, others (eg. total N, desorbable P) are becoming evident only on sandy soils. There were no detectable effects of land-use change on soil acidity, on various measures of soil C. The experiments in second rotation establishment have shown that retention of harvest residues has beneficial effects on mineral N dynamics and on concentrations of Ca, Mg and K in surface soils. For example, retaining harvest residues on a red earth soil reduced the potential for N loss after clearfelling but increased N mineralisation rates and therefore soil N supply to trees 3-4 years after establishment of a second rotation crop.
Implications	The observed differences between pasture and plantation soils have emerged within a relatively short time frame and were detectable despite being measured against a relatively high initial fertility level. They are consistent with our initial hypothesis that soil N and P supply for plant growth are likely to decline with changes in land management involving reduced input to soils of both P fertiliser and nutrient rich organic residues. If the observed trends continue, increased incidence of nutrient limitations to growth can be expected to impact on productivity unless corrective measures are taken. Implementing practices which offset declining soil nutrient status will be critical to maintaining site fertility and productivity in the long-term, even though benefits to tree growth on some sites may not be apparent immediately.


 

Project Title	Agroforestry design guidelines to balance catchment health with primary production
RIRDC Project No.:	CSM-4A
Researcher:	Dr Richard Stirzaker and Dr Rob Vertessy (Principal Investigators)
Organisation:	CSIRO Land & Water PO Box 1666, Canberra ACT (in conjunction with CSIRO Forestry and Forest Products)
Phone:	02 6246 5570 and 02 6246 5790
Fax:	02 6246 5965
Email:	Richard.stirzaker@cbr.clw.csiro.au and Rob.vertessy@cbr.clw.csiro.au
Objectives	§ To measure and predict tree water use under optimal conditions. § To review and measure tree water use under stressed conditions. § To measure and predict the competition between trees and crops for water in different agroforestry systems. § To apply a catchment model to key sites and run model scenarios to optimise catchment health with tree productivity. § To produce a booklet of guidelines to support land managers to optimise tree productivity with crop/pasture productivity and catchment health.
Background	This project arose from the 1996 JVAP workshop "Agroforestry and Hydrology – what do we need to know". One of three outcomes of this meeting was that guidelines were required that brought together agroforestry and hydrology at paddock, hillslope and catchment scales.
Research	The project started with 9 scientists from CSIRO Land & Water and CSIRO Forestry and Forest products and a total of 16 scientist are authors and co-authors in the book. Experiments were carried out in Wellington (trees over saline watertables), Moora (alley cropping), Wagga (tree spacing), Warrenbayne (break of slope) and Kattaning (tree belts). Based on the above field studies, laboratory studies and a range of computer models, the guidelines were formulated for the book (objective 5).
Outcomes	The first four objectives above all feed into the major outcome of this project –. The working title is "TREES, WATER & SALT –How to use trees to manage watertables and salinity for sustainable agriculture in Australia." The book summarises the state of the art knowledge in the field, and is being written in such a way that it is accessible to practitioners.
Implications	Understanding of salinity and a sensible management approach is hampered because the subject matter crosses disciplinary boundaries, including groundwater hydrology, agronomy, forestry, physiology and soil physics. The book has been written with input from each of these disciplines and sets out for practitioners what opportunities and limits for using trees for salinity management.
Publications	The major publication from the project will be the book, although a number of journal papers are currently submitted or in press.

Project Title	Establishment of trees on non- arable land to replace weeds
RIRDC Project No.:	DAN-126A
Researcher:	Dr M H Campbell
Organisation:	NSW Agriculture Locked Bag 21 ORANGE NSW 2800
Phone:	02 6391 3828
Fax:	02 6391 3899
Email:	malcolmcampbell@smtpgwy.agric.gov.au
Objective	To investigate methods of establishing trees on non- arable land to replace weeds.
Background	Large areas of infertile hill country in Australia infested with weeds cannot be reclaimed by sowing pastures because the pastures will not control the weeds and the process is unprofitable. One solution to this problem is to sow trees to control the weeds.
Research	This project investigated low cost and rapid methods of establishing trees on non-arable land to control serrated tussock. The methods of establishment investigated were aerial sowing and direct drilling in contrast to the normal practice of planting tree seedlings by manual labour. Ten experiments were conducted over five years.
Outcomes	Establishment for at least one species per experiment (5 to 14 species sown per experiment) was successful from 70% of aerial sowings, 90% of direct drillings and 88% of seedling plantings. The respective figure for the two most successful species was 37%, 75% and 50% for Pinus radiata and 50%, 87% and 12% for Eucalyptus viminalis. For aerial sowing and direct drilling successful establishment was defined as >1 tree per 10 m2 and for planted seedlings was defined as >80% establishment. § The major factor limiting establishment of aerial sown or direct drilled tree seedlings was competition from weeds in the first spring and summer after planting. Whereas herbicide treatments could control the weeds up to the time the young trees seedlings were 2 to 5 cm high, post emergence herbicides damaged tree seedlings too much to allow selective control of the weeds in spring. § The best time of sowing was late winter because this allowed the best control of weeds prior to sowing. § Eucalypts (E. viminalis, E. polyanthemos, E. melliodora, E. blakelyii, E. albens) were the best adapted species for establishment from aerial sowing and P. radiata and Arcacia spp. the best from direct drilling. § Serrated tussock was successfully controlled by volunteer pasture species that dominated the sown areas once they had been fenced and burning stopped. Further research should be undertaken into the control of weeds in the first spring and summer to improve establishment from direct drilling and in particular from aerial sowing. Also, further research should be undertaken into establishing tree seedlings by sowing them in canisters distributed by aircraft as investigated in USA.
Implications	This project showed that weeds can be controlled, by sowing trees on non-arable land provided the area sown is fenced off from stock and not burnt. Further research is needed to define reliable techniques for using aerial sowing but direct drilling and planting seedlings will give acceptable levels of establishment that will control weeds. Large scale demonstrations of reliable techniques are necessary to inform producers of what methods of tree establishment to use. Financial assistance will be necessary for landholders to retire land from agricultural production for the sowing of trees.
Publications	Campbell, M. H. (1999). Establishment of trees on non-arable land to replace weeds. Final Report, RIRDC Campbell, M. H. and Dowling, P. M. (1999). Establishment of trees to control serrated tussock. Proceedings 12th Australian Weeds Conference, Hobart. pp. 20-24. Campbell, M. H. and Nicol, H. I. (1998). Establishing weeds on non-arable land to control weeds. Proceedings 11th Australian Weeds Conference, Melbourne. 1, pp. 493-6. Campbell, M. H. and Nicol, H. I. (1998). Tolerance of tree seedlings to pre- and post- emergence herbicides. Proceedings 9th Australian Agronomy Conference, Wagga Wagga, pp.276-8. Jones, R. E., Vere, D. T. and Campbell, M. H. (2000). The external costs of pasture weed spread: an economic assessment of serrated tussock control. Agricultural Systems 22, 91-103.

Optimised productivity of crops and pastures
 

Project Title	Shelterbelts and crop production in north east Victoria
RIRDC Project No.:	DAV-69A
Researcher:	Dr Michael Crawford
Organisation:	Agriculture Victoria Department of Natural Resources and Environment RMB 1145 RUTHERGLEN VIC 3685
Phone:	02 6030 4500
Fax:	02 6030 4600
Email:	michael.crawford@nre.vic.gov.au
Objective	To measure the effects of shelterbelts on crop production in north east Victoria.
Background	Substantial beneficial effects of shelter on agricultural production have been claimed in countries where extensive shelter networks have been developed. A trial at Rutherglen Victoria in 1990, showed beneficial effects of shelter provided by eucalypts on wheat and oat yields in the sheltered zone. Up until now, this had been one of the few scientific trials conducted in Australia. A nationally coordinated and systematic effort to validate the reported effects of shelterbelts on crop and pasture production commenced in 1993 in the form of the National Windbreak Program. From this research and from the modelling work derived from it, it was expected that better prediction would be made of shelter values to particular situations and therefore would allow for better planning of the placement of trees on farms.
Research	From 1994 to 1996, the impact of tree shelterbelts on the growth of lupins and wheat was monitored at a site near Dookie in north east Victoria. Two shelterbelts consisting of 8-12 m high native trees were located along adjacent sides of a paddock. Crop parameters such as plant numbers, biomass, leaf area and grain yield were determined along transects emanating from each belt. To minimise soil and shelterbelt variability, a second experiment using artificial shelters made of shadecloth was conducted at Dookie in 1996 and near Rutherglen in 1997. Crop growth and yield were compared with results from similar areas in the open paddock, away from the influence of shelter.
Outcomes	Results from the tree shelterbelt experiment at Dookie were highly variable, thus precluding any significant conclusions to be drawn from this experiment. Variability resulted from inconsistencies in soil conditions (especially drainage) and shelterbelt uniformity, as well as the inherent biological variation found in crop growth. In the second experiment using artificial shelters, no significant impact of shelter was found in either year of this experiment. Crop growth and yields inside the shelters were similar to that found in the open. A possible reason for this is that average windspeeds of 2.0 ms-1 do not limit crop growth in this environment. Alternatively, shelter effects may be so small that they cannot be detected using traditional methods with the associated sampling errors that they contain.
Implications	Despite the lack of significant results in the first experiment, this project has made a major contribution to the National Windbreak Program. Significant crop yield benefits from windbreaks are unlikely in regions of low average windspeed and in areas where extreme wind events are rare. Furthermore, windbreak effects are subtle and variable. Effects may be easily masked by factors including soil variation, upwind terrain, discontinuities in windbreaks through tree death and natural variation in crop growth across the paddock. However, general conclusions on the role of tree shelterbelts on farms need to be formulated from the perspective of the National Windbreak Program.
Publications	Sudmeyer, R.A., Crawford, M.C., Meinke, H.M and Poulton, P.L. (2000). Effect of artificial wind shelters on the growth and yield of rainfed crops. Agroforestry Systems (in prep.). Crawford, M.C., Noble, P.A. and Haines, P.J. (1998). Shelterbelts and wheat production in north east Victoria. Proceedings of the 9th Australian Agronomy Conference, Wagga Wagga, NSW. pp. 685-686.


 

Project Title	Blue Gum Timberbelt Design For Alley Farming
RIRDC Project No.:	DAW-70A
Researcher:	Tony Albertsen
Organisation:	Agriculture Western Australia  PO Box 1231  BUNBURY WA 6230
Phone:	+61 8 9780 6289
Fax:	+61 8 9780 6136
Email:	talbertsen@agric.wa.gov.au
Objective	The objective of this project was to measure the production effects at the interface between pasture and Tasmanian blue gums grown for pulpwood, and then build these into an economic model which would help farmers to optimise the design of their own alley farming projects
Background	Tasmanian blue gum is being extensively planted across parts of southern Australia for the production of pulpwood. Plantings in 1999 exceeded 50,000 hectares nationally, because this crop is often more profitable than grazing. The apparent extra volume of edge trees and the anticipated shelter and hydrological benefits of these trees had suggested that blue gums in an alley farming layout would be even more profitable than plantations. Alley farming also offers the prospect of farmers remaining in working occupation of their land pursuing traditional enterprises, rather than move off the farm to make way for fence-to-fence industrial plantations.
Research	Thirty sites were selected for the establishment of plots in the trees and pasture respectively. The sites were spread over a wide area of the high rainfall agricultural zone, 600 mm to 1100 mm annually.  Pasture yield was measured each year for three years by periodical cuts at a set distances from the edge trees, in order to define the extent of pasture lost due to the competition from trees. These results were then expressed as the equivalent width of pasture lost. Tree height and diameter were measured for each of the outside three rows, for three consecutive years. Tree volume was calculated from these measurements. Harvest volume estimates were limited to six sites. A spreadsheet model (BLUEBELTS) was adapted to calculate the profitability of a blue gum alley farming project. Pasture loss distance and the extra volume of edge trees, expressed as a percentage of inside-row trees, were included in the model using the means of plot data. The model was also modified to reflect the effects of design on tree harvesting costs, and to incorporate the option of pruning edge trees.
Outcomes	Pasture loss distance clearly increases with the age of the trees. There is typically a loss of almost 10 metres of total annual pasture production in the year in which the tree crop reaches 10 years of age, which is the usual age at harvest. This loss is more pronounced at the start of the season. The project confirmed that edge tree volume is substantially greater than the volume of inside row trees. The edge effect does not extend into the plantation beyond the outside row. The effect is highly variable, but the cause of this variation could not be established due to the low number of sites with trees of harvestable age.  Economic modelling showed that narrow tree belts are generally more profitable than wide belts, and an alley width of about two tree heights is most profitable unless grazing returns are high and tree growth poor.
Implications	Farmers in the high rainfall zone can have confidence that pasture loss distance is much less than one tree height, and that edge trees produce more wood than inside trees. Further research is warranted to relate the size of the edge effect to readily measurable site characteristics. The project outcome is encouraging to farmers who find that they need to plant trees in a dispersed arrangement on a substantial part of their farms to improve catchment water balance and reduce the impact of salinity and wind on the sustainability of their farming system.

Optimised direct returns from Tree Products
 

Project Title	Development of an Australian "Farm Forestry Site Selection Manual"
RIRDC Project No.:	CAL-4A
Researcher:	Dr Richard Harper
Organisation:	Department of Conservation and Land Management Locked Bag 104 BENTLEY DELIVERY CENTRE WA 6983
Phone:	08 9334 0306
Fax:	08 9334 0327
Email:	richardh@calm.wa.gov.au
Internet:	www.calm.wa.gov.au/projects/plantations_splash.html
Objectives	§ Produce a farm forestry site selection manual; § Critical evaluation of current site selection practice in farm forestry; § Identification of priorities for future farm forestry site selection R & D; § Increase sustainability and profitability of farm forestry.
Background	Farm forestry is emerging as a major new land-use in Australia and will provide a range of economic, environmental and social benefits, such as income diversification and increased profitability for farmers, greater export income, land degradation control and increased rural employment. For these benefits to be realised, however, trees have to be grown profitability. Tree performance (survival and growth) is related to climate and soil (site) properties - if trees are planted on inappropriate sites they will grow poorly or die. Similarly, various management decisions (e.g. whether or not to cultivate, apply fertilisers, species to select and stand density) are dependent on soil and site conditions. Species and inputs can be tailored to a site’s requirements thus increasing profitability and the sustainable use of resources. It is thus critical that site selection methods are as rigorous and effective as possible.  Farm forestry, however, is moving into districts where plantation forestry has not been practised and site selection standards are not available. The Australian "Farm Forestry Site Selection Manual" will fill this gap by specifying the best methods for site-selection for farm forestry, at the regional and paddock scales. These methods will be proposed as industry standards to be used by landholders, extension advisers and the farm-forestry industry. They will also be suitable for the description of forestry experimental sites by scientists. The manual will also be suitable for use as a component of farm-forestry studies at the TAFE and undergraduate level.
Research	Project team-members visited areas of major farm forestry expansion in southern and eastern Australia and inspected and discussed site selection practice with a range of practitioners, scientists, consultants and other stakeholders.  Key literature on land evaluation for a variety of land-uses was examined.
Outcomes	Several unifying principles about farm forestry site selection are clear:  § A primary premise of all site evaluation is that methods should be explicit, quantitative, consistent and repeatable. There are constraints on the time and money that can be spent on site evaluation. § The large variation in climatic and land resource attributes across Australia requires a robust, multi-scaled system, from region to field. § The relationships between land attributes, soil management practice, and tree response are often not quantified. Thus activities such as fertilisation, cultivation or tree spacing are often still applied by prescription, rather than actual requirement.  § Many field experiments and tree breeding trials do not adequately describe the sites that the trees have been grown on. Thus, one of the largest potential benefits of site evaluation – the extension of trial results to new areas – is lost. We recommend that all trial sites are adequately characterized, and present a protocol for doing so. § New digital technologies will aid the implementation of quantitative site evaluation.
Implications	It is clear that this manual could form the basis for regional and State codes of practice for new farm forestry schemes.  The manual is also relevant to the establishment of plantations and bushland on farmland for carbon sequestration.
Publications	Ryan, P. J., Harper, R. J., Booth, T. H., McKenzie, N. J., and Gilkes, R. J. (in review). The Australian Farm Forestry Site Selection Manual. Rural Industries Research and Development Corporation, RIRDC Research Report Project CAL-4A.  Harper, R. J. (2000). Site evaluation for farmland revegetation. In Proceedings ‘Restoration with Native Species Workshop,’ Kings Park Botanical Gardens, Western Australia, 14 February 2000.  Harper, R. J. (in review). Site evaluation for the revegetation of farmland – undertaking the site survey. Tree Note Harper, R. J., and McGrath, J. F. (2000). Using soil survey for farm forestry and greenhouse sink site selection and management. ACLEP Newsletter 8,  Harper, R. J., Ryan, P. J., Booth, T. H., McKenzie, N. J., and Gilkes, R. J. (1999). The Australian "Farm Forestry Site Selection Manual". In Proceedings ‘Australian Forestry Council, Research Working Group 3 (Soils and Nutrition),’ Rotorua, New Zealand, November 15-19, 1999.  Harper, R. J., Smettem, K. R. J., and Gilkes, R. J. (2000). Land assessment to integrate trees with agriculture for carbon sequestration, salinity control and profit. In Proceedings ‘Australian and New Zealand Soils Conference,’ Lincoln University, New Zealand, 4-8 December, 2000.  Ryan, P. J., Harper, R. J., Laffan, M. D., Booth, T. H., and McKenzie, N. J. (2000). Developments in site evaluation for farm forestry in Australia and the relationship to sustainability and productivity. In Proceedings ‘Managing Forest Soils for Sustainable Productivity, 4th International Conference on Forest Soils,’ University of Vila Real, Portugal, 18-22 September, 2000.

This project was supported by the Natural Heritage Trust
 

Project Title:	Identification of pest resistant eucalypts using near-infra red spectroscopy
RIRDC Project No.:	CSE-78A
Researcher:	Dr Rob Floyd
Organisation:	CSIRO Entomology GPO Box 1700 CANBERRA ACT 2601
Phone:	02 6246 4089
Fax:	02 6246 4155
Email:	R.Floyd@ento.csiro.au
Objectives	§ To develop near-infrared reflectance spectroscopy (NIRS) methods as a means of rapid and early prediction in juvenile trees of important tree characteristics such as pest resistance. § To identify pest resistant trees of key species of eucalypts for farm forestry in southeast Australia.
Background	Application of chemical pesticides and poisons to reduce damage by insect and vertebrate pests in plantations is costly to plantation owners and also incurs hidden costs of health hazards and loss of biodiversity. It has been proposed that incorporating naturally resistant trees in plantation is an alternative to applying chemical pesticides. To include resistance traits into tree improvement programs, a rapid and effective method of detecting resistance is required. NIRS has the potential to satisfy this requirement.
Research	We used a range of feeding choice experiments to determine the resistance of individuals of a number of Eucalyptus species to feeding by insect and marsupial folivores. Once resistant trees were identified, we examined components of the leaf chemistry to determine mechanisms of resistance which were then tested using manipulation experiments. Efficient methods of preparing leaf material for NIRS analysis were tested and statistical models constructed to allow the prediction of the chemical composition of foliage and also the level of consumption by insect and marsupial herbivores. Finally, the chemistry of juvenile and adult trees was compared to determine if NIRS analysis of seedlings could be used to predict resistance of adult trees.
Outcomes	We determined the chemical basis for resistance to insect and marsupial folivores in farm forestry. An excellent understanding of some important resistance mechanisms and of the application of near-infrared spectroscopy to identifying plants that express key resistance traits has been gained. One of the strengths of this work is that the resistance traits that we have demonstrated (e.g. sideroxylonal and cineole) are strongly represented in the NIRS models that we have developed. We are now able to use NIRS to predict resistance rapidly and with great confidence since the resistance traits have been correctly identified and experimentally verified. We have demonstrated substantial cross-resistance between marsupial herbivores and one major group of insect defoliators, the Christmas beetles (Anoplognathus spp). Although all the marsupial species examined are susceptible to the effects of sideroxylonal (albeit at different concentrations), we found that a range of different insect defoliators did not respond the same way as Christmas beetles. Major differences between the chemical composition of seedlings and adult leaves of some eucalypt species have been shown.
Implications	Near-infrared spectroscopy proved to be a highly suitable tool for rapidly assessing components of natural herbivore resistance in eucalypts. The presence of some cross-resistance between insect and marsupial herbivores is particularly promising for the incorporation of resistance into genetic improvement programs. The difference between chemical profiles of leaves of juvenile and mature plants needs further investigation.
Publications	Matsuki, M., Ebber, M., Foley, W. & Floyd, R. (1998). Factors affecting leaf consumption by Christmas beetles in SE Australia. Abstract & poster, Gordon Research Conference, Los Angles. Matsuki, M., Ebber, M., Foley, W. & Floyd, R. (1998). Factors affecting leaf consumption by Christmas beetles in SE Australia. Abstract & poster, Australian Applied Entomology Research Conference, Brisbane.

Site map Contact us Feedback Links Disclaimer Privacy Statement

Last updated: October 5 2000
Copyright © RIRDC
http://www.rirdc.gov.au/comp00/aft1.html