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RESEARCH ARTICLE
Contents Vol 61(2)

Impacts of grazing management options on pasture and animal productivity in a Heteropogon contortus (black speargrass) pasture in central Queensland. 1. Pasture yield and composition

D. M. Orr A E , W. H. Burrows A D , R. E. Hendricksen A D , R. L. Clem B , P. V. Back A D , M. T. Rutherford A , D. J. Myles A D and M. J. Conway C
+ Author Affiliations
- Author Affiliations

A Department of Employment, Economic Development and Innovation, PO Box 6014, Rockhampton Mail Centre, Qld 4702, Australia.

B Department of Employment, Economic Development and Innovation, PO Box 395, Gympie, Qld 4625, Australia.

C Department of Employment, Economic Development and Innovation, Locked Mail Bag 6, Emerald, Qld 4720, Australia.

D Retired.

E Corresponding author. Email: david.orr@deedi.qld.gov.au

Crop and Pasture Science 61(2) 170-181 https://doi.org/10.1071/CP09193
Submitted: 3 July 2009  Accepted: 9 December 2009   Published: 8 February 2010

Abstract

An extensive grazing study was conducted between 1988 and 2001 in a Heteropogon contortus (black speargrass) pasture in central Queensland. The study was designed to measure the effects of stocking rate on native pasture, native pasture with legume oversown, and native pasture with animal diet supplement/spring burning on pasture and animal production. Summer rainfall throughout the study was below the long-term mean. Mean annual pasture utilisation ranged from 13% at 8 ha/steer up to 61% at 2 ha/steer. Increasing stocking rate treatments reduced total pasture yields while total yields in legume oversown treatments were similar to those in native pasture at the same stocking rate. When spring burning was possible, total yields were reduced in the subsequent autumn. Increasing stocking rate in native pasture tended to reduce H. contortus and Bothriochloa bladhii, increased the composition of intermediate species, such as B. decipiens and Chloris divaricata, and also changed the frequencies of a range of minor species. Oversowing legumes resulted in Stylosanthes scabra cv. Seca increasing from <1% of pasture composition in 1988 to 50% in 2000 and was associated with a reduction in H. contortus and changes in the frequencies of some minor species. Stocking rates heavier than 4 ha/steer resulted in annual pasture utilisation greater than 30% and were unsustainable because they reduced total yield and resulted in undesirable changes in species composition. It was concluded that pasture production was sustainable when stocking rates were maintained at 4 ha/steer, which equates to 30% annual pasture utilisation, and through the judicious use of spring burning.

Additional keywords: species composition, stocking rate, legume oversowing, burning, Heteropogon contortus pastures.


Acknowledgments

Special acknowledgment is made to the Neill-Ballantine family (Galloway Plains Pastoral Co.) for their ready co-operation and for the long-term use of land on which the study was based. Many people contributed to the overall conduct of this grazing study during its 13-year duration and it is impossible to comprehensively list all these people here. We especially thank the large number of Department of Primary Industries and Fisheries and Department of Natural Resources and Water staff who made major contributions to this study’s success. A Producer Advisory Group readily gave constructive advice throughout the study. Funding was provided by Meat and Livestock Australia.


References


Anderson ER (1993) Plants of central Queensland—their identification and uses. Information Series 192037, Queensland Department of Primary Industries, Brisbane, Qld.

Barton A (1991) Soils of the Glenwood and Galloway Plains research sites, Queensland. Technical Report, Queensland Department of Primary Industries, Brisbane, Qld.

Bortolussi G, McIvor JG, Hodgkinson JJ, Coffey SG, Holmes CR (2005) The northern Australian beef industry, a snapshot: 3. Annual liveweight gains from pasture based systems. Australian Journal of Experimental Agriculture 45, 1093–1108.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Burrows WH, Orr DM, Hendricksen RE, Rutherford MT, Myles DJ, Back PV (2010) Impacts of grazing management options on pasture and animal productivity in a Heteropogon contortus (black speargrass) pasture in central Queensland. 4. Animal production. Animal Production Science (in press). 50, open url image1

Burrows WH , Scanlan JC , Rutherford MT (1987) Native pastures in Queensland: the resources and their management. Information Series Q187023, Department of Primary Industries, Brisbane, Qld.

Clewett JF , George DA , Ooi SH , Owens DT , Partridge IJ (2002) Rainman International (version 4.1): An integrated software package of rainfall information for better management. QI02023, Department of Primary Industries Queensland.

Davies EJ (2001) Long-term impact of stocking rate and legume oversowing on landscape function in a black speargrass (Heteropogon contortus) pasture. Study Report, 4th year Project Report, Environmental Science, University of Queensland.

Day KA , Philp MW (1997) SWIFTSYND METHODOLOGY: A methodology for measuring a minimum data set for calibrating pasture and soil parameters of the pasture growth model GRASP. Appendix 3: Final Report DAQ-124A Evaluating the Risk of Pasture and Land Degradation in Native Pasture in Queensland.

Genstat (2002) ‘Genstat for Windows. Release 6.1.’ (VSN International Ltd.: Oxford, UK)

Hacker JB , Shaw NH , Mannetje L (1982) More beef from spear grass country Pasture Research at Rodd’s Bay, central Queensland, 1945–1977. CSIRO Division of Tropical Crops and Pastures Research Report No. 2.

Hendricksen RE , McLean R , Dicker RW (1985) The role of supplements and diet selection in beef production and management of tropical pastures. In ‘Proceedings of the 3rd Australian Conference on Tropical Pastures’. Rockhampton, pp. 56–67. (Tropical Grassland Society of Australia: Brisbane, Qld)

Hendricksen RE, Myles DJ, Reid DJ, Orr DM (2010) Impacts of grazing management options on pasture and animal productivity in a Heteropogon contortus (black speargrass) pasture in central Queensland. 3. Diet selection in autumn. Animal Production Science 50, (in press). open url image1

Jones RJ (2003) Effects of sown grasses and stocking rates on pasture and animal production from legume-based pastures in the seasonally dry tropics. Tropical Grasslands 37, 129–150. open url image1

Littleboy M , McKeon GM (1997) Subroutine GRASP: Grass production model. Documentation of the Marcoola version of Subroutine GRASP – Appendix 2. Evaluating the risk of pasture and land degradation in native pasture in Queensland. Final Report for Rural Industries and Research Development Corporation Project DAQ124A.

McIvor JG, Gardener CJ (1995) Pasture management in semi-arid tropical woodlands: effects on herbage yields and botanical composition. Australian Journal of Experimental Agriculture 35, 705–715.
| Crossref | GoogleScholarGoogle Scholar | open url image1

McIvor JG , Noble AD , Orr DM (1996) Review of stability and productivity of native pastures oversown with tropical legumes. Northern Australia Program Occasional Publication No. 1. Meat and Livestock Australia Ltd, North Sydney, NSW.

McKeon GM, Day KA, Howden SM, Mott JJ, Orr DM, Scattini WJ, Weston EJ (1990) Northern Australian savannas: management for pastoral production. Journal of Biogeography 17, 355–372.
| Crossref | GoogleScholarGoogle Scholar | open url image1

McLeod ND, Cook SJ (2004) The economic performance of steers grazing black speargrass pastures oversown with legumes in south Queensland, Australia. Tropical Grasslands 38, 140–153. open url image1

Noble AD, Orr DM, Middleton CH, Rogers LG (2000) Legumes in native pasture — asset or liability? A case history with stylo. Tropical Grasslands 34, 199–206. open url image1

Orchard BA, Cullis BR, Coombes NE, Virgona JM, Klein T (2000) Grazing management studies within the temperate pasture sustainability key program: experimental design and statistical analysis. Australian Journal of Experimental Agriculture 40, 143–154.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Orr DM (2004) Dynamics of plant populations in Heteropogon contortus (black speargrass) pastures on a granite landscape in southern Queensland. 4. The effects of burning on H. contortus and Aristida spp. populations. Tropical Grasslands 38, 77–87. open url image1

Orr DM, Burrows WH, Hendricksen RE, Clem RL, Rutherford MT, Conway MJ, Myles DJ, Back PV, Paton CJ (2001) Pasture yield and composition changes in a Central Queensland black speargrass (Heteropogon contortus) pasture in relation to grazing management options. Australian Journal of Experimental Agriculture 41, 477–485.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Orr DM, McKeon GM, Day KA (1991) Burning and exclosure can rehabilitate degraded black speargrass (Heteropogon contortus) pastures. Tropical Grasslands 25, 333–336. open url image1

Orr DM , O’Reagain PJ (2005) Rainfall and grazing impacts on the population dynamics of Bothriochloa ewartiana in tropical Australia. In ‘XX th International Grasslands Congress: Offered papers’. (Eds FP O’Mara, RJ Wilkins, L.’tMannetje, DK Lovett, PAM Rogers, TM Boland) p. 526. (Wageningen Academic Publishers: Wageningen, The Netherlands)

Orr DM, Paton CJ, Lisle AT (1997) Using fire to manage species composition in Heteropogon contortus (black speargrass) pastures. 1. Burning regimes. Australian Journal of Agricultural Research 48, 795–802.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Orr DM , Paton CJ , Rutherford MT (1999) Forest bluegrass (Bothriochloa bladhii) can replace black speargrass (Heteropogon contortus) in central Queensland native pasture. In ‘Proceedings VIIth International Rangelands Congress’. (Eds D Eldridge, D Freuden-berger) pp. 223–225. (International Rangeland Congress Inc.: Aitkenvale, Qld)

Orr DM, Yee MC, Myles DJ (2006) Impact of short-term exclosure from grazing on pasture recovery from drought in six Queensland pasture communities. Tropical Grasslands 40, 202–212. open url image1

Orr DM, Yee MC, Rutherford MT, Paton CJ (2010) Impacts of grazing management options on pasture and animal productivity in a Heteropogon contortus (black speargrass) pasture in central Queensland. 2. Population dynamics of Heteropogon contortus and Stylosanthes scabra cv. Seca. Crop & Pasture Science (in press). 61, open url image1

Pressland AJ , Scanlan JC , Myles DJ , Anderson ER (1991) Ground flora composition influences rainfall-runoff and soil loss in semi-arid tropical rangelands of Australia. In ‘Proceedings of the 4th International Rangelands Congress’. Montpellier, France. pp. 153–155. (CIRAD: Montpellier, France)

Sallaway MM , Waters DK (1996) Spatial variation in land degradation due to changes in grazing pressure during drought. In ‘Focus on the Future — the heat is on. Proceedings of the 9th Biennial Conference of the Australian Rangeland Society’. Port Augusta. (Eds LP Hunt, R Sinclair) pp. 108–109. (Australian Rangeland Society: Northam, WA)

Shaw NH (1978) Superphosphate and stocking rate effects on a native pasture oversown with Stylosanthes humilis in central coastal Queensland. 1. Pasture production. Australian Journal of Experimental Agriculture and Animal Husbandry 18, 788–799.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Shaw NH, Dale MB (1978) Superphosphate and stocking rate effects on a native pasture oversown with Stylosanthes humilis in central coastal Queensland. 3. The balance of native species in the pasture. Australian Journal of Experimental Agriculture and Animal Husbandry 18, 808–816.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Shaw NH, Mannetje L’t (1970) Studies on a spear grass pasture in central coastal Queensland — the effect of fertilizer, stocking rate and oversowing with Stylosanthes humilis on beef production and botanical composition. Tropical Grasslands 4, 43–56. open url image1

Silcock RG , Jones P , Hall TJ , Waters DK (2005) Enhancing pasture stability and profitability for producers in poplar box and silver-leaved ironbark woodlands. Meat and Livestock Australia Project NAP3.208 Final Report. Meat and Livestock Australia, Sydney, NSW.

Tongway D , Hindley N (2004) Manual for assessment of soil condition for tropical grasslands. CSIRO Division of Wildlife and Ecology, Australia.

Tothill JC , Gillies C (1992) ‘The pasture lands of northern Australia. Their condition, productivity and sustainability.’ Occasional Publication No. 5. (Tropical Grassland Society of Australia: Brisbane, Qld)

Tothill JC , Hargreaves JNC , Jones RM , Mc Donald CK (1992) BOTANAL – A comprehensive sampling and computing procedure for estimating pasture yield and composition. 1. Field sampling. Technical Memorandum No. 78, Division of Tropical Crops and Pastures, CSIRO, Australia.

Tothill JC, Mc Donald CK, McHarg GW, Hargreaves JNC (2008) Development options in Heteropogon contortus grassland in south-east Queensland: tree killing, legume oversowing and pasture replacement. 1. Pasture production and composition. Tropical Grasslands 42, 129–151. open url image1

Vercoe JE , Frisch JE (1985) Improving the productivity of grazing animals. In ‘Proceedings of the 3rd Australian Conference on Tropical Pastures’. Rockhampton. pp. 47–55. (Tropical Grassland Society of Australia: Brisbane, Qld)