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RESEARCH ARTICLE

Summer-growing perennial grasses are a potential new feed source in the low rainfall environment of southern Australia

Katrien Descheemaeker A F , Rick Llewellyn B , Andrew Moore C and Anthony Whitbread D E
+ Author Affiliations
- Author Affiliations

A Plant Production Systems, Wageningen University, PO Box 430, 6700 AK Wageningen, The Netherlands.

B CSIRO Agriculture Flagship, PMB 2, Glen Osmond, SA 5064, Australia.

C CSIRO Agriculture Flagship, GPO Box 1600, Canberra, ACT 2601, Australia.

D Crop Production Systems in the Tropics, Georg-August-Universität Göttingen, Grisebachstraße 6, 37077 Göttingen, Germany.

E International Crops Research Institute for the Semi-arid Tropics (ICRISAT), Patancheru, Telengana, India.

F Corresponding author. Email: katrien.descheemaeker@wur.nl

Crop and Pasture Science 65(10) 1033-1043 https://doi.org/10.1071/CP13444
Submitted: 17 December 2013  Accepted: 17 April 2014   Published: 7 October 2014

Abstract

In the Mallee region of southern Australia, the dry and variable climate results in frequent summer–autumn feed gaps, restricting the profitability of farms that combine livestock and crop enterprises. To assess the suitability of summer-growing perennial grasses to fill such feed gaps, two replicated field experiments comparing the persistence and productivity of several cultivars were conducted at Hopetoun and Karoonda. The data from these experiments also served to validate a C4 grass model, which was then used in a simulation experiment comparing productivity on two different soil types at three locations. Most grass cultivars established well except on sandy, non-wetting soils. At Hopetoun, four of five cultivars persisted over 6 years, demonstrating the tolerance of the selected cultivars to the typical long, dry summers and cold, wet winters of the region. Biomass production showed little difference between cultivars and a strong response to the amount of summer rainfall, ranging from 1500 to 3000 kg ha–1 under average seasonal conditions and peaking at 9000 kg ha–1 in the very wet summer of 2010–2011. Model performance was satisfactory (R2 0.85–0.93, RMSE 476–1673 kg ha–1, depending on the cultivar), in terms of predicting both the magnitude and the timing of biomass production. Simulation outputs indicated that biomass production closely followed seasonal trends in temperature and moisture availability. Grazing potential was highest from early summer to autumn, which coincides with the period of feed shortages and highest marginal value of forage. In areas with warm-season (October–April) rainfall averages of 175 and 225 mm, the grazing of C4 grass pastures on marginal soils would be possible in at least 40% of the years for 2 and 3 months, respectively. It was concluded that summer-growing perennials are a promising option to alleviate feed gaps on mixed crop–livestock farms in areas with at least 150 mm of rainfall from October to April.

Additional keywords: cereal–sheep systems, GRAZPLAN model, on-farm trials, panic grass, Rhodes grass.


References

Araujo LC, Santos PM, Rodriguez D, Pezzopane JRM, Oliveira PPA, Cruz PG (2013) Simulating Guinea grass production: empirical and mechanistic approaches. Agronomy Journal 105, 61–69.
Simulating Guinea grass production: empirical and mechanistic approaches.Crossref | GoogleScholarGoogle Scholar |

Bell LW, Moore AD (2012) Integrated crop–livestock systems in Australian agriculture: Trends, drivers and implications. Agricultural Systems 111, 1–12.
Integrated crop–livestock systems in Australian agriculture: Trends, drivers and implications.Crossref | GoogleScholarGoogle Scholar |

Bell LW, Robertson MJ, Revell DK, Lilley JM, Moore AD (2008) Approaches for assessing some attributes of feed-base systems in mixed farming enterprises. Australian Journal of Experimental Agriculture 48, 789–798.
Approaches for assessing some attributes of feed-base systems in mixed farming enterprises.Crossref | GoogleScholarGoogle Scholar |

Boschma SP, Lodge GM, Harden S (2008) Herbage mass and persistence of pasture legumes and grasses at two potentially different saline and waterlogging sites in northern New South Wales. Australian Journal of Experimental Agriculture 48, 553–567.
Herbage mass and persistence of pasture legumes and grasses at two potentially different saline and waterlogging sites in northern New South Wales.Crossref | GoogleScholarGoogle Scholar |

Boschma S, Lodge G, Harden S (2009) Establishment and persistence of perennial grass and herb cultivars and lines in a recharge area, North-West Slopes, New South Wales. Crop & Pasture Science 60, 753–767.
Establishment and persistence of perennial grass and herb cultivars and lines in a recharge area, North-West Slopes, New South Wales.Crossref | GoogleScholarGoogle Scholar |

Brown RA, Rosenberg NJ, Hays CJ, Easterling WE, Mearns LO (2000) Potential production and environmental effects of switchgrass and traditional crops under current and greenhouse-altered climate in the central United States: a simulation study. Agriculture, Ecosystems & Environment 78, 31–47.
Potential production and environmental effects of switchgrass and traditional crops under current and greenhouse-altered climate in the central United States: a simulation study.Crossref | GoogleScholarGoogle Scholar |

Bryant JR, Snow VO (2008) Modelling pastoral farm agro‐ecosystems: A review. New Zealand Journal of Agricultural Research 51, 349–363.
Modelling pastoral farm agro‐ecosystems: A review.Crossref | GoogleScholarGoogle Scholar |

Byrne F, Robertson MJ, Bathgate A, Hoque Z (2010) Factors influencing potential scale of adoption of a perennial pasture in a mixed crop-livestock farming system. Agricultural Systems 103, 453–462.
Factors influencing potential scale of adoption of a perennial pasture in a mixed crop-livestock farming system.Crossref | GoogleScholarGoogle Scholar |

Clark SG, Austen EA, Prance T, Ball PD (2003) Climate variability effects on simulated pasture and animal production in the perennial pasture zone of south-eastern Australia. 1. Between year variability in pasture and animal production. Australian Journal of Experimental Agriculture 43, 1211–1219.
Climate variability effects on simulated pasture and animal production in the perennial pasture zone of south-eastern Australia. 1. Between year variability in pasture and animal production.Crossref | GoogleScholarGoogle Scholar |

Cohen RDH, Stevens JP, Moore AD, Donnelly JR (2003) Validating and using the GrassGro decision support tool for a mixed grass/alfalfa pasture in western Canada. Canadian Journal of Animal Science 83, 171–182.
Validating and using the GrassGro decision support tool for a mixed grass/alfalfa pasture in western Canada.Crossref | GoogleScholarGoogle Scholar |

Collard SJ, Fisher AM (2010) Shrub-based plantings of woody perennial vegetation in temperate Australian agricultural landscapes: What benefits for native biodiversity? Ecological Management & Restoration 11, 31–35.
Shrub-based plantings of woody perennial vegetation in temperate Australian agricultural landscapes: What benefits for native biodiversity?Crossref | GoogleScholarGoogle Scholar |

Corleto A, Cazzato E, Ventricelli P, Cosentino S, Gresta F, Testa G, Maiorana M, Fornaro F, Giorgio D (2009) Performance of perennial tropical grasses in different Mediterranean environments in southern Italy. Tropical Grasslands 43, 129–138.

Corson MS, Rotz CA, Skinner RH (2007) Evaluating warm-season grass production in temperate-region pastures: A simulation approach. Agricultural Systems 93, 252–268.
Evaluating warm-season grass production in temperate-region pastures: A simulation approach.Crossref | GoogleScholarGoogle Scholar |

Dear BS, Ewing MA (2008) The search for new pasture plants to achieve more sustainable production systems in southern Australia. Australian Journal of Experimental Agriculture 48, 387–396.
The search for new pasture plants to achieve more sustainable production systems in southern Australia.Crossref | GoogleScholarGoogle Scholar |

Dear BS, Reed KFM, Craig AD (2008) Outcomes of the search for new perennial and salt tolerant pasture plants for southern Australia. Australian Journal of Experimental Agriculture 48, 578–588.
Outcomes of the search for new perennial and salt tolerant pasture plants for southern Australia.Crossref | GoogleScholarGoogle Scholar |

Di Vittorio AV, Anderson RS, White JD, Miller NL, Running SW (2010) Development and optimization of an Agro-BGC ecosystem model for C4 perennial grasses. Ecological Modelling 221, 2038–2053.
Development and optimization of an Agro-BGC ecosystem model for C4 perennial grasses.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXovVamur0%3D&md5=617238ce67da0d6e53aececeece52bffCAS |

Donnelly JR, Freer M, Moore AD (1998) Using the GrassGro decision support tool to evaluate some objective criteria for the definition of exceptional drought. Agricultural Systems 57, 301–313.
Using the GrassGro decision support tool to evaluate some objective criteria for the definition of exceptional drought.Crossref | GoogleScholarGoogle Scholar |

Donnelly JR, Freer M, Salmon EM, Moore AD, Simpson RJ, Dove H, Bolger TP (2002) Evolution of the GRAZPLAN decision support tools and adoption by the grazing industry in temperate Australia. Agricultural Systems 74, 115–139.
Evolution of the GRAZPLAN decision support tools and adoption by the grazing industry in temperate Australia.Crossref | GoogleScholarGoogle Scholar |

Finlayson JD, Lawes RA, Metcalf T, Robertson MJ, Ferris D, Ewing MA (2012) A bio-economic evaluation of the profitability of adopting subtropical grasses and pasture-cropping on crop-livestock farms. Agricultural Systems 106, 102–112.
A bio-economic evaluation of the profitability of adopting subtropical grasses and pasture-cropping on crop-livestock farms.Crossref | GoogleScholarGoogle Scholar |

Gherbin P, De Franchi A, Monteleone M, Rivelli A (2007) Adaptability and productivity of some warm‐season pasture species in a Mediterranean environment. Grass and Forage Science 62, 78–86.
Adaptability and productivity of some warm‐season pasture species in a Mediterranean environment.Crossref | GoogleScholarGoogle Scholar |

Glover JD, Culman SW, DuPont ST, Broussard W, Young L, Mangan ME, Mai JG, Crews TE, DeHaan LR, Buckley DH, Ferris H, Turner RE, Reynolds HL, Wyse DL (2010) Harvested perennial grasslands provide ecological benchmarks for agricultural sustainability. Agriculture, Ecosystems & Environment 137, 3–12.
Harvested perennial grasslands provide ecological benchmarks for agricultural sustainability.Crossref | GoogleScholarGoogle Scholar |

Harris RH, Hirth JR, Crawford MC, Bellotti WD, Peoples MB, Norng S (2007) Companion crop performance in the absence and presence of agronomic manipulation. Australian Journal of Agricultural Research 58, 690–701.
Companion crop performance in the absence and presence of agronomic manipulation.Crossref | GoogleScholarGoogle Scholar |

Harris CA, Boschma SP, Moore G (2009) Developing a more productive, persistent panic grass cultivar. Tropical Grasslands 43, 269–270.

Holzworth DP, Huth NI, deVoil PG, Zurcher EJ, Herrmann NI, McLean G, Chenu K, van Oosterom E, Snow VO, Murphy C, Moore AD, Brown HE, Whish JPM, Verrall S, Fainges J, Bell LW, Peake AS, Poulton PL, Hochman Z, Thorburn PJ, Gaydon DS, Dalgliesh NP, Rodriguez D, Cox H, Chapman S, Doherty A, Teixeira E, Sharp J, Cichota R, Vogeler I, Li FY, Wang E, Hammer GL, Robertson MJ, Dimes J, Whitbread AM, Hunt J, van Rees H, MaClelland T, Carberry PS, Hargreaves JNG, MacLeod N, McDonald C, Harsdorf J, Wedgwood S, Keating BA (2014) APSIM—evolution towards a new generation of agricultural systems simulation. Environmental Modelling & Software in press.

Isbell RF (2002) ‘The Australian Soil Classification.’ (CSIRO Publishing: Melbourne)

Johnston WH, Cornish PS, Shoemark VF (2005) Eragrostis curvula (Schrad.) Nees. complex pastures in southern New South Wales, Australia: a comparison with Medicago sativa L. and Phalaris aquatica L. pastures under rotational grazing. Australian Journal of Experimental Agriculture 45, 401–420.
Eragrostis curvula (Schrad.) Nees. complex pastures in southern New South Wales, Australia: a comparison with Medicago sativa L. and Phalaris aquatica L. pastures under rotational grazing.Crossref | GoogleScholarGoogle Scholar |

Kering MK, Butler TJ, Biermacher JT, Guretzky JA (2012) Biomass yield and nutrient removal rates of perennial grasses under nitrogen fertilization. BioEnergy Research 5, 61–70.
Biomass yield and nutrient removal rates of perennial grasses under nitrogen fertilization.Crossref | GoogleScholarGoogle Scholar |

Kiniry JR, Schmer MR, Vogel KP, Mitchell RB (2008) Switchgrass biomass simulation at diverse sites in the northern Great Plains of the U.S. BioEnergy Research 1, 259–264.
Switchgrass biomass simulation at diverse sites in the northern Great Plains of the U.S.Crossref | GoogleScholarGoogle Scholar |

Lara MAS, Pedreira CGS, Boote KJ, Pedreira BC, Moreno LSB, Alderman PD (2012) Predicting growth of Panicum maximum: An adaptation of the CROPGRO–perennial forage model. Agronomy Journal 104, 600–611.
Predicting growth of Panicum maximum: An adaptation of the CROPGRO–perennial forage model.Crossref | GoogleScholarGoogle Scholar |

Lawes RA, Robertson MJ (2008) Seasonal variability of Rhodes grass production in the northern West Australia wheatbelt. In ‘14th Australian Society of Agronomy Conference’. 21–25 September 2008, Adelaide, S. Aust. (Australian Society of Agronomy/The Regional Institute Ltd: Gosford, NSW) Available at: www.regional.org.au/au/asa/2008/concurrent/pasture-production/5821_lawes_robertson.htm

Legates DR, McCabe GJ (1999) Evaluating the use of “goodness‐of‐fit” measures in hydrologic and hydroclimatic model validation. Water Resources Research 35, 233–241.
Evaluating the use of “goodness‐of‐fit” measures in hydrologic and hydroclimatic model validation.Crossref | GoogleScholarGoogle Scholar |

Li FY, Snow VO, Holzworth DP (2011) Modelling seasonal and geographical pattern of pasture production in New Zealand. New Zealand Journal of Agricultural Research 54, 331–352.
Modelling seasonal and geographical pattern of pasture production in New Zealand.Crossref | GoogleScholarGoogle Scholar |

Lloyd DL (1981) Markarikari grass—(Panicum coloratum Var. Markarkariense)—A review with particular reference to Australia. Tropical Grasslands 15, 44–52.

Lloyd DL, Smith KP, Clarkson NM, Weston EJ, Johnson B (1991) Ley pastures in the subtropics. Tropical Grasslands 25, 181–188.

Madakadze IC, Coulman BE, Mcelroy AR, Stewart KA, Smith DL (1998) Evaluation of selected warm season grasses for biomass production in areas with a short growing season. Bioresource Technology 65, 1–12.
Evaluation of selected warm season grasses for biomass production in areas with a short growing season.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXksFeit7Y%3D&md5=e2992d3fbfc6c810280e20baa08a0f61CAS |

McCormick LH, McGufficke BR, Harden S, Ross BA (1998) Subtropical grass evaluation for pastures in northern NSW. In ‘Proceedings of the 9th Australian Agronomy Conference’. Wagga Wagga, NSW. (Australian Society of Agronomy/The Regional Institute Ltd: Gosford, NSW) Available at: www.regional.org.au/au/asa/1998/1/028mccormick.htm

McCosker TH, Teitzel JK (1975) A review of Guinea grass (Panicum maximum) for the wet tropics of Australia. Tropical Grasslands 9, 177–190.

McIvor JG, Smith DF (1973) Plant factors influencing the nutritive value of some temperate annual pasture species. Australian Journal of Experimental Agriculture and Animal Husbandry 13, 404–410.
Plant factors influencing the nutritive value of some temperate annual pasture species.Crossref | GoogleScholarGoogle Scholar |

Milford R, Minson DJ (1968) The digestibility and intake of six varieties of Rhodes grass (Chloris gayana). Australian Journal of Experimental Agriculture and Animal Husbandry 8, 413–418.
The digestibility and intake of six varieties of Rhodes grass (Chloris gayana).Crossref | GoogleScholarGoogle Scholar |

Millar GD, Badgery WB (2009) Pasture cropping: a new approach to integrate crop and livestock farming systems. Animal Production Science 49, 777–787.
Pasture cropping: a new approach to integrate crop and livestock farming systems.Crossref | GoogleScholarGoogle Scholar |

Moore AD (2009) Opportunities and trade-offs in dual-purpose cereals across the southern Australian mixed-farming zone: a modelling study. Animal Production Science 49, 759–768.
Opportunities and trade-offs in dual-purpose cereals across the southern Australian mixed-farming zone: a modelling study.Crossref | GoogleScholarGoogle Scholar |

Moore G, Barrett-Lennard P (2006) Subtropical grasses. In ‘Perennial pastures for Western Australia.’ pp. 129–134. Bulletin 4690. (Department of Agriculture and Food WA: South Perth, W. Aust.)

Moore AD, Ghahramani A (2013) Climate change and broadacre livestock production across southern Australia. 1. Impacts of climate change on pasture and livestock productivity, and on sustainable levels of profitability. Global Change Biology 19, 1440–1455.
Climate change and broadacre livestock production across southern Australia. 1. Impacts of climate change on pasture and livestock productivity, and on sustainable levels of profitability.Crossref | GoogleScholarGoogle Scholar | 23504950PubMed |

Moore AD, Donnelly JR, Freer M (1997) GRAZPLAN: Decision support systems for Australian grazing enterprises. III. Pasture growth and soil moisture submodels, and the GrassGro DSS. Agricultural Systems 55, 535–582.
GRAZPLAN: Decision support systems for Australian grazing enterprises. III. Pasture growth and soil moisture submodels, and the GrassGro DSS.Crossref | GoogleScholarGoogle Scholar |

Moore G, Sanford P, Wiley T (2006) ‘Perennial pastures for Western Australia.’ Bulletin 4690. (Department of Agriculture and Food WA: South Perth, W. Aust.)

Moore AD, Bell LW, Revell DK (2009) Feed gaps in mixed-farming systems: Insights from the Grain & Graze Program. Animal Production Science 49, 736–748.
Feed gaps in mixed-farming systems: Insights from the Grain & Graze Program.Crossref | GoogleScholarGoogle Scholar |

Moore AD, Alcock DJ, Pope LC, Powells JI (2010) Validating the GRAZPLAN pasture model for native grasslands of the Monaro region. In ‘Food security from sustainable agriculture. Proceedings of the 15th Australian Agronomy Conference’. Palmerston North, NZ, 15–18 November 2010. (Eds H Dove, RA Culvenor) (Australian Society of Agronomy/The Regional Institute Ltd: Gosford, NSW) Available at: www.regional.org.au/au/asa/2010/farming-systems/simulation-decision-support/7187_moore.htm

Nichols PGH, Loi A, Nutt BJ, Evans PM, Craig AD, Pengelly BC, Dear BS, Lloyd DL, Revell CK, Nair RM, Ewing MA, Howieson JG, Auricht GA, Howie JH, Sandral GH, Carr SJ, de Koning CT, Hackney BF, Crocker GJ, Snowball R, Hughes SJ, Hall EJ, Foster KJ, Skinner PW, Barbetti MJ, You MP (2007) New annual and short-lived perennial pasture legumes for Australian agriculture—15 years of revolution. Field Crops Research 104, 10–23.
New annual and short-lived perennial pasture legumes for Australian agriculture—15 years of revolution.Crossref | GoogleScholarGoogle Scholar |

Nie ZN, Miller S, Moore GA, Hackney BF, Boschma SP, Reed KFM, Mitchell M, Albertsen TO, Clark S, Craig AD, Kearney G, Li GD, Dear BS (2008) Field evaluation of perennial grasses and herbs in southern Australia. 2. Persistence, root characteristics and summer activity. Australian Journal of Experimental Agriculture 48, 424–435.
Field evaluation of perennial grasses and herbs in southern Australia. 2. Persistence, root characteristics and summer activity.Crossref | GoogleScholarGoogle Scholar |

Pengelly BC, Hall E, Auricht GC, Bennell M, Cook BG (2006) Identifying subtropical pasture species for grazing systems in the Mallee–Wimmera. CSIRO Sustainable Ecosystems, Canberra, ACT.

Reed KFM, Nie ZN, Miller S, Hackney BF, Boschma SP, Mitchell ML, Albertsen TO, Moore GA, Clark SG, Craig AD, Kearney G, Li GD, Dear BS (2008) Field evaluation of perennial grasses and herbs in southern Australia. 1. Establishment and herbage production. Australian Journal of Experimental Agriculture 48, 409–423.
Field evaluation of perennial grasses and herbs in southern Australia. 1. Establishment and herbage production.Crossref | GoogleScholarGoogle Scholar |

Robertson SM (2006a) Crop stubbles are as important for sheep production as annual pastures in the Victorian Mallee. Australian Journal of Experimental Agriculture 46, 993–1003.
Crop stubbles are as important for sheep production as annual pastures in the Victorian Mallee.Crossref | GoogleScholarGoogle Scholar |

Robertson SM (2006b) Predicting pasture and sheep production in the Victorian Mallee with the decision support tool, GrassGro. Australian Journal of Experimental Agriculture 46, 1005–1014.
Predicting pasture and sheep production in the Victorian Mallee with the decision support tool, GrassGro.Crossref | GoogleScholarGoogle Scholar |

Smith FW (1986) Pasture species. In ‘Plant analysis—an interpretation manual’. (Ed. DJ Reuter) pp. 100–119. (Inkata Press: Melbourne)

Stout WL (1994) Evaluation of the SPUR model for grasslands of the northeastern United States. Agronomy Journal 86, 1001–1005.
Evaluation of the SPUR model for grasslands of the northeastern United States.Crossref | GoogleScholarGoogle Scholar |

Thomas DT, Lawes RA, Descheemaeker K, Moore AD (2014) Selection of crop cultivars suited to the location combined with astute management can reduce crop yield penalties in pasture cropping systems. Crop & Pasture Science 65, 1022–1032.

Verburg K, Bond WJ, Hirth JR, Ridley AM (2007) Lucerne in crop rotations on the Riverine Plains. 3. Model evaluation and simulation analyses. Australian Journal of Agricultural Research 58, 1129–1141.
Lucerne in crop rotations on the Riverine Plains. 3. Model evaluation and simulation analyses.Crossref | GoogleScholarGoogle Scholar |

Wales W, Doyle P, Pearce G (1990) The feeding value of cereal straws for sheep. I. Wheat straws. Animal Feed Science and Technology 29, 1–14.
The feeding value of cereal straws for sheep. I. Wheat straws.Crossref | GoogleScholarGoogle Scholar |

Whitbread A, Craig S (2010) The potential of summer-growing grasses to persist and produce out-of-season forage in the Victorian Mallee. In ‘Food security from sustainable agriculture. Proceedings of the 15th Australian Agronomy Conference’. November 2010, Christchurch, New Zealand. (Australian Society of Agronomy/The Regional Institute Ltd: Gosford, NSW) Available at: www.regional.org.au/au/asa/2010/pastures-forage/lucerne/6979_whitbreada.htm.

Whitbread A, Llewellyn R, Gobbett D, Davoren B (2008) EM38 and crop-soil simulation modelling can identify differences in potential crop performance on typical soil zones in the Mallee. In ‘Global issues, paddock action. Proceedings of 14th Agronomy Conference’. Adelaide, S. Aust. 21–25 September 2008. (Ed. M Unkovich) (Australian Society of Agronomy/The Regional Institute Ltd: Gosford, NSW) Available at: www.regional.org.au/au/asa/2008/poster/agronomy-landscape/5823_whitbread.htm

Whitbread AM, Hall CA, Pengelly BC (2009) A novel approach to planting grass - legume pastures in the mixed farming zone of southern inland Queensland, Australia. Crop & Pasture Science 60, 1147–1155.
A novel approach to planting grass - legume pastures in the mixed farming zone of southern inland Queensland, Australia.Crossref | GoogleScholarGoogle Scholar |

Wilson JR, ’t Mannetje L (1978) Senescence, digestibility and carbohydrate content of buffel grass and green panic leaves in swards. Australian Journal of Agricultural Research 29, 503–516.
Senescence, digestibility and carbohydrate content of buffel grass and green panic leaves in swards.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE1cXksFKntL8%3D&md5=6bc40e5fd085c903cda33c2279c5cdd5CAS |