Project Title	The effect of windbreaks on crop growth on the Atherton Tablelands in North Queensland.
RIRDC Project No.:	DAQ-147A
Researcher:	Amanda Snell, Simon Brooks.
Organisation:	Queensland Forest Research Institute DPI Forestry 83 Main St ATHERTON, QLD 4883
Phone:	07 40915200.
Fax:	07 40915211.
Email:	snella@dpi.qld.gov.au, brookssj@dpi.qld.gov.au
Objectives	To quantify the effects of windbreaks on crops such as maize, potatoes and peanuts.
Background:	Research was conducted on a privately owned farm just north of Atherton, on a flat site on deep red soil, The site has several three and four row windbreaks that were established in 1991.
Research	Intensive measurements of crop morphology, growth and yield were conducted annually from 1994 to 1998 at increasing distances from the windbreak. Soil and climatic parameters were also regularly recorded. Data from these measures have been used to calculate changes in crop yields as distance from the windbreak increases, and to assist in explaining these changes. This data has also been utilised in the crop growth and windbreak models by APSRU.  Tree growth and windbreak composition has also been investigated.
Outcomes	Results over four potato crops have shown on increased yield in windbreak sheltered plants, and this may be due to a reduction in leaf damage from reduced wind flow. The total yield increase was between 6 and 9% out to 40 times the height of the windbreak. In 1998 a peanut crop showed a similar total increase of 12% in the yield of sheltered plants, and reductions in water stress closer to the windbreak. A three row windbreak of Melaleuca sp (low row), Eucalyptus sp (middle row) and Eucalyptus microcorys and Pinus caribaea var hondurensis (tall row) can result in a windbreak with a maximum height of 11m at age 7, that reduces wind flow to a maximum of between 44 and 54%. Positive influences of an 11m high windbreak extend up to 350 metres into a paddock and, for example, in 1997 resulted in an additional 11.4 tonnes of potatoes in one paddock. Four years of maize crop data suggests that there is no significant change in yield between sheltered and unsheltered treatments. However, significant decreases in maize leaf damage have also been measured for sheltered plants.
Implications	The results from the project suggest that the presence of relatively young windbreaks can positively affect the yield of horticultural crops such as potatoes and peanuts through a reduction in wind-speed and a decrease abrasive damage to plants. This result will have application to orchard crops such as mangoes, avocados, macadamia nuts, lychees and bananas that are grown on the tablelands.

 

Project Title	Effect of windbreaks on crop productivity in South Australia
RIRDC Project No.:	UA-25A
Researcher:	Ian K. Nuberg, Stephen J. Mylius
Organisation:	University of Adelaide Department of Agronomy and Farming Systems Roseworthy Campus, ROSEWORTHY SA
Phone:	08 8303 7729
Fax:	08 8303 7979
Objectives	To evaluate the value of windbreaks in South Australian cropping systems by determining their impact on water relations, biomass production and yields.
Background:	The shelter provided by windbreaks has been reported to enhance crop productivity by several mechanisms: directly through growth processes modified by microclimate changes, and physical protection of the crop from abrasion and lodging, and indirectly through its effect on soil conservation and soil moisture accession. Most of the windbreak literature reports the effect of shelter under very different conditions of climate and management than found in Australia. There was a need to evaluate the magnitude and mechanism of crop response to shelter under various farming systems in Australia. This project, which focussed on the investigation of the effect of shelter on crop water use, was the South Australian component of the National Windbreak Program.
Research	This project completed four years of field measurements of mainly wheat, but also canola, faba beans and oats under shelter created by an Aleppo pine windbreak as well as that created by an artificial windbreak and full enclosures. Detailed growth, yield and soil moisture measurements were made as well as a comprehensive soil characterisation of the natural windbreak site. During this period the crops were exposed to four very different seasons, from drought to well-watered. Wheat was also grown in sealed-system lysimeters under sheltered and exposed conditions to determine the effect of shelter on the efficiency with which water is used to produce plant biomass.
Outcomes	Elements of the classic windbreak signature could be detected in the yield responses of 6 out of 8 crop years and this was more pronounced in dry years. The yield differences of wheat across the paddock were well correlated with cumulative water use of the crop. However, these results are not unequivocal as covariate analysis of wheat and bean yield data with soil texture indicated that yield variation across the paddock could be explained by variation in depth to calcareous clay loam. Nevertheless, the windbreak did alter the microclimate such that wheat (but not canola) flowered earlier in the sheltered zone. It was also clearly shown that sheltered conditions will enhance the biomass production of wheat While there was no difference in total water use under sheltered and unsheltered conditions, that water was used to benefit vegetative growth but not grain filling. It was concluded that although shelter does affect the physiology of crops grown in this environment the effect on final yield is relatively subtle compared with other sources of yield variation. However, shelter does enhance biomass production of wheat most likely through its effect on the efficiency with which the crop uses water.
Implications	The shelter created by windbreaks in South Australian farming systems has a measurable effect on physiology and water use of wheat. While this may not result in greater grain yields the enhanced biomass production will be of value to farmers involved in fodder production (eg cereal hay and most likely lucerne). The results also imply that shelter may have a stronger effect on the yields of non-cereal crops and so further research on pulse and oilseed crops is warranted. The general value of windbreaks in this environment will be through their effect on protecting both crop and soil from the physical damage of strong winds.

Optimised Direct Returns from Tree Products

Project Title	National farm tree improvement program workshop
RIRDC Project No.:	SAR-17A
Researcher:	Peter Bulman
Organisation:	Primary Industries & Resources SA Box 752 MURRAY BRIDGE SA 5253
Phone:	08 8539 2117
Fax:	08 8523 5646
Email:	bulman.peter@saugov.sa.gov.au
Objectives	To improve national co-ordination of low rainfall farm forestry provenance trials, initially by holding a workshop of key players to evaluate the merit of: Choosing benchmark provenances so that comparisons can be made between regions & sites  Sharing genetic material and adopting common methodology (trial design) Optimising the resources available to source and breed superior material
Background:	Efforts to identify superior genetic material for low-rainfall farm forestry species have historically been limited and disparate. This deficiency has been well recognised at a range of fora (Yanchep workshop 1994, National Agroforestry Working Group (RWG 11) 1996 and AACM workshop last week in Adelaide). Such qualities include: good health and vigour eg tolerance to difficult sites, high water use for salinity and productivity for wood and plant products  extra height to optimise shelter benefits good form eg straight trunks for timber or erect growth habit for broombush.
Research	The workshop was held in the Adelaide Hills, 3-5th November 1998 and incorporated paper presentations, workshop sessions and informal discussion.
Outcomes	improved knowledge of the current state of low rainfall tree selection and improvement research; and identification of research and information gaps—presented in the workshop proceedings  a resolution to develop a collaborative national project proposal to locate, equitably share and develop superior genetic material for key species for hardwoods (Eucalyptus cladocalyx, E.maculata, E. occidentalis and E camaldulensis), softwoods (Pinus pinaster, P. radiata, P. brutia/halepensis) and short-rotation biomass crops (mallee oil species), incorporating standard protocols for designing, measuring and reporting on provenance trials and seed orchards  formation of a geographically-based, five-member Australian Low Rainfall Tree Improvement Group (ALRTIG) to guide the direction of collaborative work in the three key ‘modules’
Implications	Since the workshop such a national collaborative project has been developed (led by CSIRO) and funded, paving the way for more concerted and cost-effective development of low rainfall farm forestry in dry temperate and Mediterranean climatic zones of Australia.

 

Project Title	High value trees on farms
RIRDC Project No.:	UNE-34A
Researcher:	Alison Specht
Organisation:	School of Resource Science and Management Southern Cross University,  P.O. Box 157,  LISMORE N.S.W. 2480
Phone:	02 6620 3755
Fax:	02 6621 2669
Objectives	The objectives of this project were to: identify high value cabinet timber species appropriate for use on farms;  identify key site conditions commensurate with optimal growth; identify key management practices that improve growth; and test the value and manner of obtaining information from non-traditional plantings.
Background:	The use of high-value trees is an attractive component of diverse farming enterprises in the subtropics. Such trees can potentially provide a good medium to long-term alternative income source, with proportionally low maintenance in comparison with other farm activities. The selection of species, their management and monitoring, is, however, problematic, as little information is currently available. Most landholders are sceptical about the economic viability of the use of high-value trees on their properties and their ability to manage them. As a primary step in encouraging the adoption of such a new innovation, good information on possible species, their growth rates, site requirements and management, needs to be made available.
Research	There were four major components to the research: existing plantations of cabinet timber species were selected and site and management characteristics recorded using a systematic data recording system devised for the project; the growth of the species in each plantation was measured, with special attention to two experimental plantations established under National Afforestation Program funding, and various chemical and physical attributes assessed; the growth of fourteen species common to at least two plantations was compared with the various physical attributes of the sites on which the plantations were located.  the results were collated, the various species grouped into growth potential classes, qualities of suitable sites for each species explored, and management recommendations made where observations were sufficiently reliable.
Outcomes	It was demonstrated that it was possible to gain useful information from non-experimental plantations. There was a significant difference in the performance of the species planted at the various sites. The species were grouped into three classes according to growth rate to four years of age: high, medium and low. The highest growth rates were very favourable, with height increments of greater than one metre per annum. Moisture conditions proved to be the most indicative of both species suitability and performance. Several species clearly showed a preference for an ample supply of rain (? 160mm per month), while the growth of others was reduced at high rainfall, preferring a median amount of rain (circa 140mm per month). A high soil-water-holding capacity was important for a few species. Management factors were not as strongly related to performance as climate and soil factors, mainly due to the large variation in climate and soils between the sites and the lack of rigorous comparisons of treatments. All species showed a physiological behaviour consistent with a preference for organic soils, and a preference for a median (circa 15) to high (circa 22) C/N ratio was observed in several species. The benefits of mixed species and of variations in planting design were few. A couple of factors did emerge that are worthy of note, including the dominating effect of Acacia melanoxylon in mixed species plantings, the apparent benefit to Toona ciliata of having close neighbours, and the necessity for care in design of small mixed species plantings to avoid loss of early emergents.
Implications	With further work on aspects of soil fertility, management and design, and the effective dissemination of information and knowledge, high value cabinet species on farms will be an increasingly attractive proposition for the landholder in the subtropical east coast of Australia.

Cost Effective Multi-Purpose Agroforestry Systems

Project Title	Native forests on farms productive farm forestry through sustainable management of trees on farms
RIRDC Project No.:	AAC-2A
Researcher:	Mark Parsons
Organisation:	FORTECH 7-11 Barry Drive TURNER ACT 2612
Phone:	02 6248 6900
Fax:	02 6248 6999
Objectives	To provide a basis for developing a strategy for the sustainable management of native forests on farms.
Background:	Native forests on farms are an important component of Australia’s native forest sector. They account for around one quarter of the area of productive native forest in Australia. Despite the significance of private native forest resources in Australia, there is a limited farm forestry culture among landholders. There is an increasing focus on private sector resources throughout Australia which reflects increasing pressure on publicly owned forest resources, recognition of the need for sustainable forest management on both public and private land, and an increasing recognition of the commercial opportunities of forest management as part of agricultural businesses. RIRDC has initiated a project to develop a strategy to encourage and enable landowners to manage their forests to produce commercial products that provide a viable source of farm revenue while also sustaining non-commercial forest values.
Research	This project canvassed information available on the extent and types of private native forests in Australia, the economic contribution of these forests in each of the States, and the requirements for sustainable management of these forests, including sustainable yield calculations, market access, the legislative and regulatory framework for commercial forestry on private land, and the social and cultural factors that impact also. The development and progress of management processes are addressed, including farm forestry programs and the Regional Forest Agreement (RFA) process, which aims to establish the basis for long term sustainable forest development across all land tenures, and has led to an increased focus on private forest resources in Australia. Following this investigation and analysis, impediments to the further development of commercial farm forestry were identified.
Outcomes	The analysis of private native forest resources is severely limited by a lack of basic information on the extent and nature of these forest resources. In strategies designed to develop the sustainable management of native forests on farms, key issues to be addressed include: the need for strategic direction and support at a national level; removal of legal and regulatory impediments to the sustainable management of private native forests; the need for reliable and accessible regional information on the status and potential of private native forests; the need for increased landholder skills with respect to silviculture, forest management and marketing forest products; the need to assist landholders evaluate the potential for managing native forest resources within the economic context of whole farm planning; and the lack of sufficient markets for the full range of non-sawlog products.
Implications	Encouraging and facilitating the sustainable management of native forests on farms by the above actions may hasten the development of a farm forestry culture in Australia.

 

Project Title	An assessment of commercial prospects for planted tree species in the low rainfall zones of Australia
RIRDC Project No.:	AGT-4A
Researcher:	Peter Chudleigh
Organisation:	Agtrans Research ,  PO Box 385,  TOOWONG QLD 4066
Phone:	07 3870 9564
Fax:	07 3371 3381
Objectives	To assess the commercial opportunities for growing a range of tree species in the medium to low rainfall areas of Australia, and  To establish priorities by commercial product and species type to assist resource allocation in R&D funding by the Joint Venture Agroforestry Committee.
Background:	Sustainability benefits are being sought from widespread plantings of trees in many agroecological zones of Australia. In particular the impacts of dryland salinity may be alleviated by tree planting. Many of these impacts are most severe in the medium to low rainfall areas of eastern, southern and western Australia. The identification of land use activities that may provide commercial returns would be extremely valuable to the attainment of an increase in planted areas that may in turn provide additional sustainability benefits. Relevant information on the prospective markets and economics for various tree species and product forms suitable to this zone was important to assist the Committee with further R&D planning.
Research	The study has followed a framework of defining various product forms, the market for such products and the economics of actually establishing trees to target the particular markets. Further dimensions addressed are those of a species list and assessment criteria. Information sources included various researchers, Landcare Groups, Government Departments commercial and industrial organisations, written literature and the internet. Information on the sustainability impacts has not been given much attention in line with the prime objective of the project to assess commercial profitability. However, any assessment of the overall economics of producitng different product forms can only be indicative unless the sustainability benefits and costs are considered.
Outcomes	Economic analyses were carried out for four agroforestry enterprises: sawntimber, firewood, biomass for electricity and eucalyptus oil production. Of the four enterprises analysed, the most commercially viable operation for low rainfall agroforestry was eucalyptus oil production. The most promising commercial opportunities identified for the low rainfall (400-600mm rainfall) zone include the following. Planting for fodder species, production of eucalyptus oil, and electricity produced from by-products and residues. Two important concepts in considering commercial prospects are that of flexible production systems and multiple products. Also, a number of uncertainties exist for low rainfall zone agroforestry which could affect the economic viability of agroforestry enterprises in general. These include the threat of species dying after a series of poor seasons. Also, limited knowledge is known about how many of these species might adapt to a plantation situation. Design could also be very important in the capturing of sustainability benefits that might be targeted from low rainfall agroforestry. When included in economic assessments of the agroforestry enterprises, sustainability impacts can have a significant impact on the economic viability from the viewpoint of the private landholder, as well as society. As well as sustainability benefits, carbon credits, if they eventuate, could provide additional income required to make the 'almost commercial' enterprises economically viable.
Implications	Commercial agroforestry in the low rainfall region of Australia is unlikely to be as profitable as in the high rainfall zone due to lower growth rates, less established infrastructure and greater distance to markets. However, this study has demonstrated that significant prospects exist and benefits should be capturable with further private and public R&D investment and encouragement of innovation and infrastructure support by government.

 

Project Title	Ultra-short duration agroforestry rotations for low rainfall areas (Phase Farming with Trees)
RIRDC Project No.:	CAL 3A
Researcher:	Dr Richard J. Harper
Organisation:	WA Department of Conservation and Land Management; CSIRO Land and Water,  University of WA (Soil Science)
Phone:	08 9334 0306
Fax:	08 9334 0327
Email:	richardh@calm.wa.gov.au
Objectives	Determine whether phase farming with trees in low (<400 mm) rainfall areas can rapidly de-water farming catchments at risk from salinity by depleting unsaturated stored soil water and reducing recharge while producing utilizable products.
Background:	Trees are recognised as an effective means of containing salinity, which threatens over 11.8 Mha of productive land in Australia. Uncertainties about appropriate species, their placement and long lags until commercial return may inhibit farm tree planting. A method, which offers certainty of de-watering target areas and producing a commercial product in a very short period, may enhance tree planting.  Phase Farming with Trees (PFT) is designed to use trees grown in very short rotations (3-5 years) to rapidly de-water farming catchments, at risk of salinity by depleting unsaturated soil water storage and reducing recharge. Trees would form temporary elements in rotations with annual crops; this increasing the sustainability of current farming systems, while allowing farming to continue.
Research	A $25,000 desk-top study was undertaken. This (a) reviewed existing ultra-short rotation agroforestry systems, (b) identified likely end-products of the system, (c) modelled the likely effects of the system on catchment water balances for typical environments in Western Australia and the Murray Darling Basin, (d) identified likely impacts on soil physical, chemical and biological properties and (e) undertook an overall economic analysis, bringing both products and the value of improved land and sustainable land-use to account.
Outcomes	The study suggests that the system is highly promising in specific environments in terms of both hydrological effectiveness and positive benefits on soil biological fertility. The economic analysis suggests that the system will be marginally economic, in its own right in areas with low rainfall (<400 mm). Reducing costs of establishment, identifying tree products with greater value and bringing land conservation benefits into account would improve PFT returns.
Implications	Potential benefits include decreased salinization, improved farm cash-flows, improved soil structure and reduced soil-borne disease. It is suggested that the project now be considered for full funding of a detailed trial and demonstration of the system’s potential.

 
 

Project Title	Growing Trees on Cotton Farms, a guide to assist cotton farmers decide how, when, where and why to plant trees
RIRDC Project No.:	QDN - 2A
Researcher:	Peter Voller
Organisation:	Dept of Natural Resources PO Box 589 DALBY Q 4405
Phone:	07 46699576
Fax:	07 46625310
Email:	peter.voller@dnr.qld.gov.au
Objectives	To provide cotton farmers with information on tree growing with particular relevance to their industry.
Background:	Cotton farms are characterised by heavy or clay soils, flat or moderately sloping landform, highly mechanised agronomy, including aerial spraying and innovative or progressive land managers. There are a number of opportunities for integration of trees into cotton farming systems and there has been an expressed interest from growers for more information on the subject.
Research	This project entailed the compilation of a report on existing knowledge of tree growing relevant to cotton growing areas. A range of specialist authors were involved in the production of a package which contains information on tree growing for a number of purposes, such as spray drift capture, windbreaks, wood production, salinity management, creek bank stability and nature conservation. The package also contains information on establishment and management techniques of relevance to cotton growing areas and a number of case studies of farms already planting trees.
Outcomes	3000 copies of the publication 'Growing Trees on Cotton Farms' have been produced, a copy is to be sent to each cotton grower in Australia. Further information is to be provided in a series of field days to be organised through late 1999 and early 2000.
Implications	The publication of this booklet should provide cotton farmers with an additional source of information on the subject of tree growing on their land. It is expected this will stimulate interest in farm forestry, spray drift capture and other functional uses fro tree planting.

Effective Communications

Project Title	Decision support tools for adoption of agroforestry
RIRDC Project No.:	DAW-84A
Researcher:	Peter P Eckersley
Organisation:	Agriculture Western Australia  PO Box 1231  BUNBURY WA 6230
Phone:	+61 8 9780 6204
Fax:	+61 8 9780 6136
Email:	peckersley@agric.wa.gov.au
Objectives	To promote the adoption of agroforestry systems by providing farmers with decision aids to quantify the impact of agroforestry adoption on the farm business.
Background:	A limited number of commercial tree crops have shown great potential for improving farming systems in the high rainfall zone, slowing or reversing land degradation and meet the growing demand for wood fibre. However, adopting agroforestry is a big step to take for the manager of a small business that is used to a regular annual cashflow, and unsure of the performance of these trees. A particular challenge is to integrate the projected costs, prices and yields into a measure of profit to compare it with traditional farming. Most farmers and farm advisers have little experience of, or information about, best bet commercial tree crops. They do not have easy tools to perform discounted cashflow analysis, which is needed to compare long rotation crops with traditional enterprises. It was proposed to design a computer-based tool that would be simpler than the simulation models which can only be used by agency specialists.
Research	Campbell White & Associates Pty Limited was contracted by Agriculture WA to design a set of such tools. The consultants identified the need for such a tool (model) to be linear, so the user can easily work through it in one pass. It should require a minimum of key strokes. The user should be able to select one of a set of best bet agroforestry enterprises, customise the budget to fit their own farm, and observe the expected profitability relative to normal land use. Several versions of a model were tested by a network of agroforestry practitioners in three southern States.
Outcomes	Campbell White & Associates have developed AGROFORESTRY CALCULATOR. This is a user-friendly spreadsheet-based tool for farmers and their advisers to estimate the profitability of best-bet agroforestry projects. The user selects a predefined forestry enterprise that already has production, cost and management information associated with it. Within each region, information on each enterprise must first be entered by an experienced agroforestry professional. The model can hold a large number of enterprises. Options include comparison with an annuity and addition of a landcare benefit. It is proposed that AGROFORESTRY CALCULATOR and the user manual be made available on the Agro-economic Models Database at Agriculture Western Australia for down-loading over the internet.
Implications	Farm forestry specialists in all States now have the opportunity (and obligation) to supply detailed information on best bet tree crop options to farmers and advisers in a form in which they can assess profitability for themselves.

Last updated: 17 November 1999
Copyright © RIRDC
http://www.rirdc.gov.au/99comp/aft3.htm