A comparison of stocking methods for beef production in northern Australia: pasture and soil surface condition responses

Abstract

Historical stocking methods of continuous, season-long grazing of pastures with little account of growing conditions have caused some degradation within grazed landscapes in northern Australia. Alternative stocking methods have been implemented to address this degradation and raise the productivity and profitability of the principal livestock, cattle. Because information comparing stocking methods is limited, an evaluation was undertaken to quantify the effects of stocking methods on pastures, soils and grazing capacity. The approach was to monitor existing stocking methods on nine commercial beef properties in north and south Queensland. Environments included native and exotic pastures and eucalypt (lighter soil) and brigalow (heavier soil) land types. Breeding and growing cattle were grazed under each method. The owners/managers, formally trained in pasture and grazing management, made all management decisions affecting the study sites. Three stocking methods were compared: continuous (with rest), extensive rotation and intensive rotation (commonly referred to as ‘cell grazing’). There were two or three stocking methods examined on each property: in total 21 methods (seven continuous, six extensive rotations and eight intensive rotations) were monitored over 74 paddocks, between 2006 and 2009. Pasture and soil surface measurements were made in the autumns of 2006, 2007 and 2009, while the paddock grazing was analysed from property records for the period from 2006 to 2009. The first 2 years had drought conditions (rainfall average 3.4 decile) but were followed by 2 years of above-average rainfall. There were no consistent differences between stocking methods across all sites over the 4 years for herbage mass, plant species composition, total and litter cover, or landscape function analysis (LFA) indices. There were large responses to rainfall in the last 2 years with mean herbage mass in the autumn increasing from 1970 kg DM ha–1 in 2006–07 to 3830 kg DM ha–1 in 2009. Over the same period, ground and litter cover and LFA indices increased. Across all sites and 4 years, mean grazing capacity was similar for the three stocking methods. There were, however, significant differences in grazing capacity between stocking methods at four sites but these differences were not consistent between stocking methods or sites. Both the continuous and intensive rotation methods supported the highest average annual grazing capacity at different sites. The results suggest that cattle producers can obtain similar ecological responses and carry similar numbers of livestock under any of the three stocking methods.

Integrated overview of results from a farmlet experiment which compared the effects of pasture inputs and grazing management on profitability and sustainability

“…In rotationally grazed systems, there are compromises and trade-offs that occur between pasture and animal production such as the lower legume levels and lower levels of per-head and per-hectare production (Saul and Chapman 2002). Hall et al (2011) compared three grazing systems, from continuous grazing through to intensive grazing, under extensive commercial conditions in Queensland and found that diet quality tended to be lower in the more intensive grazing systems. Others too have found that longer grazing rest periods can result in lower-quality herbage because of a higher proportion of stem to digestible leaf (Waller et al 2001).…”

“…While there are recorded cases of farm managers and proponents of intensive grazing management claiming benefits of such systems, including increased soil phosphorus, stocking rates and profits (McCosker 2000;Cawood 2004), there are also publications where some of the claims have been refuted (Waugh 1997;Dowling et al 2005;Hall et al 2011). The earliest of these papers, written by a grazier from central NSW, reported unsatisfactory cattle growth when he implemented 'time control grazing' on his property.…”

“…After this experience, he resorted to a less intensive form of rotational grazing, with a rest period of~30 days (Waugh 1997). In a recent report of grazing systems on rangelands across inland Queensland, Hall et al (2011) found that stocking rate was a much more important driver of performance than was grazing system. However, shortly after the release of these findings, the methodology used in the project was reportedly criticised by proponents of time-control grazing and holistic resource management (Cawood 2011).…”

How Biodiversity-Friendly Is Regenerative Grazing?

“…Species richness and diversity was unaffected by ReGM in sown pastures (Scott, 2001), semiarid grassland (Weigel et al, 1989;Hillenbrand et al, 2019;Oliva et al, 2021), semi-arid shrubland (Beukes and Cowling, 2000), and mesic (>650 mm a −1 MAP) grassland (Jacobo et al, 2006;Dorrough et al, 2012;Chamane et al, 2017a;Kurtz et al, 2018). Reduction in species richness under ReGM ranged from 10% (Hall et al, 2014) to over 80% (Scott-Shaw and Morris, 2015), with grasses (Allington and Vallone, 2011), forbs (Lawrence, 2019) and shrubs (McManus et al, 2018) negatively affected by intense grazing and trampling, especially during droughts (Souther et al, 2020). Regenerative grazing increased plant species (Earl et al, 2003) and life-form diversity (Barnes and Howell, 2013) over time compared to ungrazed areas (Paine and Ribic, 2002;Girard-Cartier and Kleppel, 2017) as well as to rangeland grazed continuously (Lalampaa, 2016;Odadi et al, 2017;Rantso et al, 2021;Wang et al, 2021) or rotationally at a lower intensity (Laliberté and Tylianakis, 2012).…”

Landscape function analysis to assess soil processes on farms following ecological restoration and changes in grazing management

“…There are various strategies and methods reduced biodiversity, diminished soil stability, impaired nutrient cycling, decreased water infiltration and greater rainfall runoff. All of these factors leave the soil susceptible to erosion, resulting in changes to soil, geomorphic and hydrological processes (Greene et al, 1994;Lal, 2010;Silburn et al, 2011;Hall et al, 2014). Degraded soil has an impaired capacity to provide ecosystem services such as water and nutrients for plant growth.…”