The extent and cost of mallee–crop competition in unharvested carbon sequestration and harvested mallee biomass agroforestry systems
R. A. Sudmeyer A D , T. Daniels B , H. Jones B and D. Huxtable CA Department of Agriculture and Food Western Australia, Melijinup Rd, Esperance, WA 6450, Australia.
B Formerly Department of Agriculture and Food Western Australia, Melijinup Rd, Esperance, WA 6450, Australia.
C Equinox Environmental Pty Ltd, 6 Craigie Crescent, Manning, WA 6152, Australia.
D Corresponding author. Email: rsudmeyer@agric.wa.gov.au
Crop and Pasture Science 63(6) 555-569 https://doi.org/10.1071/CP12129
Submitted: 3 April 2012 Accepted: 23 July 2012 Published: 18 September 2012
Journal Compilation © CSIRO Publishing 2012 Open Access CC BY-NC-ND
Abstract
Mallee-based agroforestry has potential to provide farmers with new income sources derived from biofuels, biofeedstocks, and carbon sequestration. Although mallees are planted on >12 700 ha across the south-west of Western Australia, very little commercial harvesting of mallee has occurred to date. The development of biomass processing industries is constrained by lack of robust information regarding the productivity of integrated mallee and agricultural systems. This study addresses this constraint by quantifying the productivity and economics of agricultural crops and pastures growing in the competition zone adjacent to mallee belts at 15 sites across the Western Australian wheatbelt. The sites covered a range of climate and edaphic conditions, three mallee species (Eucalyptus polybractea R Baker, E. loxophleba ssp. lissophloia LAS Johnson and KD Hill, or E. kochii ssp. plenissima (CA Gardner) Brooker), various crop and pasture rotations, and various mallee harvest-management treatments.
Mallee–crop competition was negatively correlated with rainfall and positively correlated with mallee age and size, and greater for crops than pasture. Consequently, extent and magnitude of competition were highly variable across sites and years. On average, mallee–crop competition extended 11.3 m from unharvested belts and reduced crop and pasture yields by 36% within 2–20 m of the mallee belts relative to open paddock yields. This is similar to what has been reported for taller tree species. Harvesting mallees reduced competition such that crop and pasture yield was reduced by 22 or 27% relative to open paddock yields for mallees harvested at 3- or 6+-year intervals, respectively.
The economic cost of mallee–crop competition on agricultural enterprises was also highly variable between sites, and between years within individual sites. Averaged across all site-years, the opportunity cost of competition was equivalent to forgoing agricultural production for 14.4 m on each side of unharvested mallee belts, or 9–10 m on each side of harvested belts.
Farmers with mallee agroforestry systems will need to manage the economic impacts of competition by reducing agricultural input costs in the competition zone, timing crop-grazing rotations with mallee harvests, ensuring that the width of alleys is at least 25 times the height of the mature trees, and possibly root-pruning mallees in unharvested or long harvest interval systems.
This research has shown that mallee–crop competition presents a significant cost to farmers and must be considered when designing mallee agroforestry systems. The findings have relevance for the development of appropriate biomass and carbon sequestration pricing benchmarks for mallee plantings.
Additional keywords: biofuel, competition zone, E. polybractea, E. loxophleba subsp. lissophloia, E. kochii subsp. Plenissima, opportunity cost, tree–crop competition.
References
ABARE (2009) ‘Australian commodity statistics 2009.’ (Australian Bureau of Agricultural and Resource Economics: Canberra)ABARES (2011) ‘Agricultural commodities: December quarter 2011. Vol. 1. No. 2.’ (Australian Bureau of Agricultural and Resource Economics and Sciences: Canberra)
Bankwest (2006) ‘BankWest benchmarks: 2005–2006 season.’ (BankWest Agribusiness Centre: Perth, W. Aust.)
Bankwest (2008) ‘Planfarm BankWest benchmarks: 2007–2008 season.’ (Planfarm, BankWest Agribusiness Centre: Perth, W. Aust.)
Bartle JR, Abadi A (2010) Towards sustainable production of second generation bioenergy feedstocks. Energy & Fuels 24, 2–9.
| Towards sustainable production of second generation bioenergy feedstocks.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXht1SnsbfL&md5=573776e2da9849c11e713762292f11e7CAS |
Bartle J, Abadi A and Thomas Q (2012) Economic analysis. In ‘Productivity of mallee agroforestry systems. The effect of harvest and competition management regimes’. RIRDC Publication No. 11/162. (Eds A Peck, R Sudmeyer, D Huxtable, J Bartle, D Mendham) pp. 98–124. (Rural Industries Research and Development Corporation: Canberra)
Bennell MR, Verbyla AP (2008) Quantifying the response of crops to shelter in the agricultural regions of South Australia. Australian Journal of Agricultural Research 59, 950–957.
| Quantifying the response of crops to shelter in the agricultural regions of South Australia.Crossref | GoogleScholarGoogle Scholar |
Bennett D, Simons J, Speed R (2011) Hydrological impacts of integrated oil mallee farming systems. Department of Agriculture and Food, Resource Management Technical Report 377, Perth, W. Aust.
Berndes G, Bird N, Cowie A (2010) Bioenergy, land use change and climate change mitigation – Background Technical Report. IEA Bioenergy: ExCo:2010 : 03. Available at: www.ieabioenergy.com/LibItem.aspx?id=6927
Bird PR, Jackson TT, Kearney GA, Williams KW (2002) Effect of two tree windbreaks on adjacent pastures in south-western Victoria, Australia. Australian Journal of Experimental Agriculture 42, 809–829.
| Effect of two tree windbreaks on adjacent pastures in south-western Victoria, Australia.Crossref | GoogleScholarGoogle Scholar |
Brandle JR, Hodges L, Tyndall J, Sudmeyer RA (2009) Windbreak practices. In ‘North American agroforestry: an integrated science and practice’. 2nd edn (Ed. HE Garrett) pp. 75–104. (America Society of Agronomy Inc.: Madison, WI)
Brooksbank K, White DA, Veneklaas EJ, Carter JL (2011) Hydraulic redistribution in Eucalyptus kochii subsp. borealis with variable access to fresh groundwater. Trees
| Hydraulic redistribution in Eucalyptus kochii subsp. borealis with variable access to fresh groundwater.Crossref | GoogleScholarGoogle Scholar |
Campbell NA, Arnold GW (1973) The visual assessment of pasture yield. Australian Journal of Experimental Agriculture and Animal Husbandry 13, 263–267.
| The visual assessment of pasture yield.Crossref | GoogleScholarGoogle Scholar |
Cooper D, Olsen G, Bartle J (2005) Capture of agricultural surplus water determines the productivity and scale of new low-rainfall woody crop industries. Australian Journal of Experimental Agriculture 45, 1369–1388.
| Capture of agricultural surplus water determines the productivity and scale of new low-rainfall woody crop industries.Crossref | GoogleScholarGoogle Scholar |
Crosbie RS, Wilson B, Hughes JD, McCulloch C (2008) The upscaling of transpiration from individual trees to areal transpiration in tree belts. Plant and Soil 305, 25–34.
| The upscaling of transpiration from individual trees to areal transpiration in tree belts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXjsVGitbg%3D&md5=ebea08ab6daee3c5532791920ae73521CAS |
Department of Agriculture and Food Western Australia (2005) ‘Gross margins guide 2005 Western Australia: representative gross margins for crop and livestock enterprises of the agricultural regions of Western Australia.’ (Department of Agriculture and Food: Perth, W. Aust.)
Ecker S, Kancans R, Thompson L (2011) Drivers of practice change in land management in Australian agriculture: preliminary national survey results. Science and Economics Insights, Issue 2.1. Australian Bureau of Agricultural and Resource Economics-Bureau of Rural Sciences, Canberra.
Ellis T, Hatton T, Nuberg I (2005) An ecological optimality approach for predicting deep drainage from tree belts of alley farms in water-limited environments. Agricultural Water Management 75, 92–116.
| An ecological optimality approach for predicting deep drainage from tree belts of alley farms in water-limited environments.Crossref | GoogleScholarGoogle Scholar |
Farm Weekly (2006) Farm budget guide 2006. Farm Weekly, Perth, W. Aust.
Farm Weekly (2007) Farm budget guide 2007. Farm Weekly, Perth, W. Aust.
Farm Weekly (2008) Farm budget guide 2008. Farm Weekly, Perth, W. Aust.
Farm Weekly (2009) Farm budget guide 2009. Farm Weekly, Perth, W. Aust.
Farm Weekly (2010) Farm budget guide 2010. Farm Weekly, Perth, W. Aust.
Garnaut R (2011) Garnaut Climate Change Review—Update 2011. Update Paper 4: Transforming rural land use. www.garnautreview.org.au/update-2011/update-papers/up4-key-points.html
George-Jaeggli B, Meinke H, Carberry PS, de HN Maia A, Voller P (1998) Variations in wheat yield behind windbreaks in southern Queensland.In ‘Agronomy, growing a greener future? Proceedings of the 9th Australian Agronomy Conference’. 20–23 July 1998, Wagga Wagga, NSW. (Eds DL Michalk, JE Pratley)
GRDC (2010) Managing resistance on fencelines and crop margins. Glyphosate Resistance Fact Sheet. Grains Research and Development Corporation, Canberra.
Huth NI, Robertson MJ, Poulton PA (2010) Regional differences in tree–crop competition due to soil, climate and management. Crop & Pasture Science 61, 763–770.
| Regional differences in tree–crop competition due to soil, climate and management.Crossref | GoogleScholarGoogle Scholar |
Huxtable D, Peck A, Bartle J, Sudmeyer R (2012) Tree biomass. In ‘Productivity of mallee agroforestry systems. The effect of harvest and competition management regimes’. RIRDC Publication No. 11/162. (Eds A Peck, R Sudmeyer, D Huxtable, J Bartle, D Mendham) pp. 5–58. (Rural Industries Research and Development Corporation: Canberra)
IEA (2009) Bioenergy—the impact of indirect land use change. Summary and Conclusions from the IEA Bioenergy ExCo63 Workshop. IEA Bioenergy: ExCo:2009 : 04. Available at: www.ieabioenergy.com/DocSet.aspx?id=6214&ret=lib
Isbell RF (1996) ‘The Australian Soil Classification.’ (CSIRO Publishing: Melbourne)
Jones HK, Sudmeyer RA (2002) Economic assessment of windbreaks on the southeast coast of Western Australia. Australian Journal of Experimental Agriculture 42, 751–762.
| Economic assessment of windbreaks on the southeast coast of Western Australia.Crossref | GoogleScholarGoogle Scholar |
Knight A, Blott K, Portelli M, Hignett C (2002) Use of shrub belts to control leakage in three dryland cropping environments. Australian Journal of Agricultural Research 53, 571–589.
| Use of shrub belts to control leakage in three dryland cropping environments.Crossref | GoogleScholarGoogle Scholar |
Lefroy EC, Stirzaker RJ, Pate JS (2001) The influence of tagastaste (Chamaecytisus proliferus Link.) trees on the water balance of an alley cropping system on deep sand in south-western Australia. Australian Journal of Agricultural Research 52, 235–246.
| The influence of tagastaste (Chamaecytisus proliferus Link.) trees on the water balance of an alley cropping system on deep sand in south-western Australia.Crossref | GoogleScholarGoogle Scholar |
Marshall E, Weinberg M, Wunder S, Kaphengst T (2011) EuroChoices. The Agricultural Economics Society and the European Association of Agricultural Economists 10, 43–49.
Oliver YM, Lefroy EC, Stirzaker R, Davies CL (2005) Deep-drainage control and yield: the trade-off between trees and crops in agroforestry systems in the medium and low rainfall areas of Australia. Australian Journal of Agricultural Research 56, 1011–1026.
| Deep-drainage control and yield: the trade-off between trees and crops in agroforestry systems in the medium and low rainfall areas of Australia.Crossref | GoogleScholarGoogle Scholar |
Ong CK, Wilson J, Deans JD, Mulayta J, Raussen T, Wajja-Musukwe N (2002) Tree-crop interactions; manipulations of water use and root function. Agricultural Water Management 53, 171–186.
| Tree-crop interactions; manipulations of water use and root function.Crossref | GoogleScholarGoogle Scholar |
Pannell DJ (2001) Explaining non-adoption of practices to prevent dryland salinity in Western Australia: Implications for policy. In ‘Land degradation’. (Ed. A Conacher) (Kluwer: Dordrecht)
Peverill KI, Sparrow LA and Reuter DJ (1999) ‘Soil analysis: an interpretation manual.’ (CSIRO Publishing: Melbourne)
Queensland Government (2011) Silo Data Drill. Available at: www.longpaddock.qld.gov.au/silo/
Robinson N, Harper RJ, Smettem KRJ (2006) Soil water depletion by Eucalyptus spp. integrated into dryland agricultural systems. Plant and Soil 286, 141–151.
| Soil water depletion by Eucalyptus spp. integrated into dryland agricultural systems.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xps1Wju74%3D&md5=f180dcb13b00bb4846e62aa8f082c08eCAS |
Saltlandgenie (2011) Unit 7 Saltland Toolbox – salinity indicators.Available at: www.saltlandgenie.org.au/all-about-saltland/unit-7-toolbox/measuring-salinity-and-waterlogging.htm
Smith FP (2009) Assessing the habitat quality of oil mallees and other planted farmland vegetation with reference to natural woodland. Ecological Management & Restoration 10, 217–227.
| Assessing the habitat quality of oil mallees and other planted farmland vegetation with reference to natural woodland.Crossref | GoogleScholarGoogle Scholar |
Sudmeyer RA (2001) Tree and crop growth in an oil mallee alley system: the effect of soil type and competition management. In ‘Proceedings of Vegetation Recovery in Degraded Land Areas Workshop’. Kalgoorlie, Western Australia, 27 October–3 November 2001. (Promoco Conventions Pty Ltd: Perth, W. Aust.)
Sudmeyer RA, Daniels T (2010) ‘The golden wreath wattle as an alternative to the mallee eucalypt for alley systems; comparative growth, water use, nutrient use and competitiveness of Acacia saligna and Eucalyptus polybractea.’ RIRDC Publication No. 10/071. (Rural Industries Research and Development Corporation: Canberra)
Sudmeyer R, Flugge F (2005) The economics of managing tree-crop competition in windbreak and alley systems. Australian Journal of Experimental Agriculture 45, 1403–1414.
| The economics of managing tree-crop competition in windbreak and alley systems.Crossref | GoogleScholarGoogle Scholar |
Sudmeyer RA, Adams M, Eastham J, Scott PR, Hawkins W, Rowland I (2002a) Broad-acre crop yield in the lee of windbreaks in the medium and low rainfall areas of south-western Australia. Australian Journal of Experimental Agriculture 42, 739–750.
| Broad-acre crop yield in the lee of windbreaks in the medium and low rainfall areas of south-western Australia.Crossref | GoogleScholarGoogle Scholar |
Sudmeyer RA, Hall DJM, Eastham J, Adams M (2002b) The tree-crop interface: The effects of root-pruning in south-western Australia. Australian Journal of Experimental Agriculture 42, 763–772.
| The tree-crop interface: The effects of root-pruning in south-western Australia.Crossref | GoogleScholarGoogle Scholar |
Sudmeyer RA, Speijers J, Nicholas BD (2004) Root distribution of Pinus pinaster, P. radiata, Eucalyptus globulus and E. kochii and associated soil chemistry in agricultural land adjacent to tree lines. Tree Physiology 24, 1333–1346.
| Root distribution of Pinus pinaster, P. radiata, Eucalyptus globulus and E. kochii and associated soil chemistry in agricultural land adjacent to tree lines.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhtFGmsL7L&md5=a5f341381d0137c5a080b9bfe3d61e31CAS |
Thornthwaite CW (1948) An approach toward a rational classification of climate. Geographical Review 38, 55–94.
| An approach toward a rational classification of climate.Crossref | GoogleScholarGoogle Scholar |
Unkovich M, Blott K, Knight A, Mock I, Rab A, Portelli M (2003) Water use, competition, and crop production in low rainfall, alley farming systems of south-eastern Australia. Australian Journal of Agricultural Research 54, 751–762.
| Water use, competition, and crop production in low rainfall, alley farming systems of south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
URS (2009) ‘Oil Mallee industry development plan for Western Australia.’ (Oil Mallee Association: Perth, W. Aust.) Available at: www.fpc.wa.gov.au/content_migration/_assets/documents/plantations/industry_plans/oil_mallee_idp.pdf
Woodall GS, Ward BH (2002) Soil water relations, crop production and root pruning of a belt of trees. Agricultural Water Management 53, 153–169.
| Soil water relations, crop production and root pruning of a belt of trees.Crossref | GoogleScholarGoogle Scholar |
