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1
Banks, Robert, Laura Wendling, Kaye Basford, Anthony Ringrose-Voase, and Vera Banks. "Beneficial soil profile differences associated with tropical grass pastures on sodic texture contrast soils in Northern New South Wales." Soil Research 58, no. 2 (2020): 207. http://dx.doi.org/10.1071/sr19140.
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Volunteer native pastures on widespread sodic texture contrast soils in northern New South Wales slopes and plains are known for their limited agricultural production. Fertilised tropical grass pastures on these soils are reported to have much increased pasture production, deeper, more abundant root mass and greater soil profile moisture storage. The subsoil physical differences between native and tropical grass pastures are not well understood. This observational study compared root abundance, soil structure and soil physical parameters (dispersion, bulk density, porosity and pore distribution) in sodic texture contrast soils under native and adjacent, well established and fertilised tropical pastures in a 14-year chronosequence. The physical differences observed may have contributed to improved soil water storage reported by other authors. Fourteen years after establishment, mean root abundance was significantly lower in soils under native pasture and greater in the tropical grass pasture system with 4600 and 8400 m of roots m–3 respectively. Dispersion values were high in native pastures but soils under tropical pastures had to be physically worked to cause dispersion. Bulk density under native pasture was significantly higher than in tropical grass pastures by 0.08 g cm–3 at 0–10 cm and by 0.2 g cm–3 in the upper B horizons. Total soil porosity of topsoils and upper B horizons was consequently lower in native than in tropical grass pasture. Tropical grass pasture upper B horizons had a three-fold greater macroporosity (pores > 30 µm), than under native pastures. This is equivalent to significantly greater potential water flow through stable macropores in dense sodic B horizons in tropical pastures. These findings indicate that pasture system selection and management positively affects deep soil structural properties which promote pasture productivity. The study contributes to a better understanding of mechanisms of published deeper water storage in tropical grass pasture systems on these normally low production soils.
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Mitchell, M. L., M. R. McCaskill, and R. D. Armstrong. "Phosphorus fertiliser management for pastures based on native grasses in south-eastern Australia." Crop and Pasture Science 70, no. 12 (2019): 1044. http://dx.doi.org/10.1071/cp19217.
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Approximately 3.1 Mha (22%) of the agricultural area of south-eastern Australia can be classified as native pasture. There is the assumption that, owing to the widespread occurrence of low-fertility soils in Australia, native grass species do not respond to increased phosphorus (P) fertility. Currently, there are no industry recommendations of target soil-test P values for native-grass-based pastures. This paper reviews the responses of perennial native pasture species endemic to south-eastern Australia to P application in controlled environments, surveys, replicated experiments and paired-paddock trials. Eighty-seven site-years of trial data where different levels of P were applied, conducted over the last two decades, on native-based pastures in south-eastern Australia are reviewed. Data indicate that application of P fertilisers to native grass pastures can increase dry matter (DM) production and maintain pasture stability. However, minimum targets for herbage mass (800 kg DM/ha) and groundcover (80%) are required to ensure persistence of perennial native grasses. Stocking rates also need to match carrying capacity of the pasture. Based on previous research, we recommend target soil-test (Olsen; 0–10 cm) P levels for fertility-tolerant native grass pastures, based on Microlaena stipoides, Rytidosperma caespitosum, R. fulvum, R. richardsonii, R. duttonianum and R. racemosum, of 10–13 mg/kg, whereas for pastures based on fertility-intolerant species such as Themeda triandra, lower levels of <6 mg/kg are required to ensure botanical stability.
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Vere, D. T., R. E. Jones, and M. H. Campbell. "The economics of temperate pasture systems on the central and southern Tablelands of New South Wales." Rangeland Journal 23, no. 2 (2001): 159. http://dx.doi.org/10.1071/rj01003.
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Pastures are the basis of most forms of agricultural production on the New South Wales central and southern tablelands. Pastures occupy the bulk of the region's landmass and pasture-based livestock production annually contributes more than three-quarters of the regional gross value of rural production. Throughout the region, there is substantial variation in pasture composition, ranging from high quality introduced perennial grasses and legumes to pastures comprising mainly low quality native species. This paper examines the economics of the main categories of temperate pastures over a range of soil fertility-rainfall environments on the south-eastern tablelands areas of New South Wales. Using a linear programming model and discounted development budgets, the results demonstrate the strong influence of the environment on the economics of the individual pasture systems. The highest economic returns in both the short and longer-terms were to the introduced perennial grass pastures in most of the environments. Pastures based on introduced legumes and the high quality native species also generated sound economic returns, although there are recognised problems with the persistence of the legume pastures. Over time, the returns to the better quality native pastures compare favourably with the introduced legumes and are better suited to acidic soils than the perennial grasses. Low quality native species produced relatively poor economic returns in all environments and unfortunately, are the main pasture type in the region's less favourable environments.
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Radrizzani, Alejandro, H. Max Shelton, Scott A. Dalzell, and Gunnar Kirchhof. "Soil organic carbon and total nitrogen under Leucaena leucocephala pastures in Queensland." Crop and Pasture Science 62, no. 4 (2011): 337. http://dx.doi.org/10.1071/cp10115.
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Soil organic carbon (OC) and total nitrogen (TN) accumulation in the top 0–0.15 m of leucaena–grass pastures were compared with native pastures and with continuously cropped land. OC and TN levels were highest under long-term leucaena–grass pasture (P < 0.05). For leucaena–grass pastures that had been established for 20, 31, and 38 years, OC accumulated at rates that exceeded those of the adjacent native grass pasture by 267, 140, and 79 kg/ha.year, respectively, while TN accumulated at rates that exceeded those of the native grass pastures by 16.7, 10.8, and 14.0 kg/ha.year, respectively. At a site where 14-year-old leucaena–grass pasture was adjacent to continuously cropped land, there were benefits in OC accumulation of 762 kg/ha.year and in TN accumulation of 61.9 kg/ha.year associated with the establishment of leucaena–grass pastures. Similar C : N ratios (range 12.7–14.5) of soil OC in leucaena and grass-only pastures indicated that plant-available N limited soil OC accumulation in pure grass swards. Higher OC accumulation occurred near leucaena hedgerows than in the middle of the inter-row in most leucaena–grass pastures. Rates of C sequestration were compared with simple models of greenhouse gas (GHG) emissions from the grazed pastures. The amount of carbon dioxide equivalent (CO2-e) accumulated in additional topsoil OC of leucaena–grass pastures ≤20 years old offset estimates of the amount of CO2-e emitted in methane and nitrous oxide from beef cattle grazing these pastures, thus giving positive GHG balances. Less productive, aging leucaena pastures >20 years old had negative GHG balances; lower additional topsoil OC accumulation rates compared with native grass pastures failed to offset animal emissions.
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Nadolny, Christopher. "Towards integrating farming and conservation: the role of native pastures." Pacific Conservation Biology 4, no. 1 (1998): 70. http://dx.doi.org/10.1071/pc980070.
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Agriculture has almost certainly contributed to the decline of native vegetation and wildlife in rural Australia. A prevalent culture supports agricultural systems that rely on the use of exotic plants and animals and greater use of chemicals and machinery. In general, these systems do not fully utilize or take account of the indigenous biota. The full implications of implementing such farming systems on a landscape scale are seldom considered. I use the grazing industry on the Northern Tablelands of New South Wales to illustrate two contrasting approaches: (1) "pasture improvement" involving replacement of native with exotic species versus (2) retention and management of existing native and naturalized pasture species. Pasture improvement has been refined by extensive agronomic research, plant selection and field testing of techniques. Nevertheless, the approach is losing support among farmers because of high inputs required to maintain "improved" pastures, the fragility of these pastures during droughts, low commodity prices, longterm declines in soil structure and increases in soil acidity. Other side-effects include tree decline, reduced diversity of indigenous herbaceous plant communities and loss of wildlife. Using native pastures may offer some solutions to these problems, but the level of understanding required to manage them effectively is limited. Exotic sown pastures have no clear advantage in areas with poor soils and irregular rainfall, and the environmental impacts of new developments involving large-scale pasture improvement can be unacceptable. I conclude that native and naturalised pastures are the best option for most of the region and sown pastures should be used strategically.
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Hennessy, D. W., D. J. McLennan, P. J. Williamson, and S. G. Morris. "Changes in characteristics of pastures in the coastal subtropics when grazed by cattle during years of low rainfall." Australian Journal of Experimental Agriculture 38, no. 8 (1998): 813. http://dx.doi.org/10.1071/ea98078.
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Summary. The effect of continuous grazing on pasture composition and quality was assessed on 2 pasture types in a subtropical environment. The pastures were native stocked at 1 cow/2.5 ha, and previously improved stocked at 1 cow/1.6 ha. In August 1990, carpet grass (Axonopus affinus) was the major species in both the native (49.8%) and improved (61.3%) pastures. However, the proportion of carpet grass decreased during the study to 33% in the native pasture and 30% in the improved pasture in February 1994. In the native pasture, blady grass (Imperata cylindrica) increased at the expense of carpet grass, whereas in the improved pasture higher quality grasses, and to a lesser extent Giant Parramatta grass (Sporobolus indicus), increased at the expense of carpet grass. Overall, dry matter on offer and green dry matter depended on rainfall and these peaked in late summer. Dry matter on offer differed between non-drought and drought periods in both pastures and was ≤3500 kg/ha in drought months in the native pasture and ≥3500 kg/ha in comparable months in the improved pasture. Green dry matter was higher in pastures towards the end of the summer growing season (83%, March 1992) and lower during many of the drought months (12%, May 1991). Grazing pressure (liveweight 0.75/t green dry matter) was highest in August, the crucial period for weed incursion. Organic matter digestibility was highest following rain in late spring (November 1990; 69%, improved pasture) but lowest in the absence of rain (November 1993; 38%, native pasture). The proportion of green dry matter in the native pasture was not related to organic matter digestibility nor to the nitrogen content of plucked pasture samples. However, in the improved pasture the proportion of green dry matter was related to organic matter digestibility on 3 occasions but not to nitrogen content.
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Garden, D. L., P. M. Dowling, D. A. Eddy, and H. I. Nicol. "The influence of climate, soil, and management on the composition of native grass pastures on the central, southern, and Monaro tablelands of New South Wales." Australian Journal of Agricultural Research 52, no. 9 (2001): 925. http://dx.doi.org/10.1071/ar98184.
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Pastures on 126 properties on the central, southern, and Monaro tablelands were surveyed to determine their botanical composition. Data on climate, soils, pasture sowing, fertiliser history, and stock management were collected to relate current composition to environmental factors and previous management. Native grass-based pastures were found to be widespread, and in many cases, pastures were dominated by native grasses, despite many decades of pasture improvement. Seventeen genera of native perennial grasses comprising over 35 species were identified. The most common species on the central tablelands were Austrodanthonia spp., Bothriochloa macra, and Microlaena stipoides; on the southern tablelands, Austrodanthoniaspp. and M. stipoides; and on the Monaro, Poa spp., Austrodanthonia spp., Themeda australis, and Austrostipa spp. Soil type was the most important factor affecting species distribution, and other soil attributes such as texture, pH, P, and N were also important. Environmental (rainfall) and management (superphosphate application, stock type, stocking rate) factors also influenced distribution. The significant areas of native grass pastures that were found suggest a decline in sown species and a recolonisation of sown pastures with native grasses. The potential for manipulation of botanical composition of these grasslands is discussed, together with their value for production and sustainability.
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Burrows, W. H., D. M. Orr, R. E. Hendricksen, M. T. Rutherford, D. J. Myles, P. V. Back, and R. Gowen. "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 50, no. 4 (2010): 284. http://dx.doi.org/10.1071/an09145.
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Steer liveweight gains were measured in an extensive grazing study conducted in a Heteropogon contortus (black speargrass) pasture in central Queensland between 1988 and 2001. Treatments included a range of stocking rates in native pastures, legume-oversown native pasture and animal diet supplement/spring‐burning pastures. Seasonal rainfall throughout this study was below the long-term mean. Mean annual pasture utilisation ranged from 13 to 61%. Annual liveweight gains per head in native pasture were highly variable among years and ranged from a low of 43 kg/steer at 2 ha/steer to a high of 182 kg/steer at 8 ha/steer. Annual liveweight gains were consistently highest at light stocking and decreased with increasing stocking rate. Annual liveweight gain per hectare increased linearly with stocking rate. These stocking rate trends were also evident in legume-oversown pastures although both the intercept and slope of the regressions for legume-oversown pastures were higher than that for native pasture. The highest annual liveweight gain for legume-oversown pasture was 221 kg/steer at 4 ha/steer. After 13 years, annual liveweight gain per unit area occurred at the heaviest stocking rate despite deleterious changes in the pasture. Across all years, the annual liveweight advantage for legume-oversown pastures was 37 kg/steer. Compared with native pasture, changes in annual liveweight gain with burning were variable. It was concluded that cattle productivity is sustainable when stocking rates are maintained at 4 ha/steer or lighter (equivalent to a utilisation rate around 30%). Although steer liveweight gain occurred at all stocking rates and economic returns were highest at heaviest stocking rates, stocking rates heavier than 4 ha/steer are unsustainable because of their long-term impact on pasture productivity.
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Gardener, CJ, MR McCaskill, and JG McIvor. "Herbage and animal production from native pastures and pastures oversown with Stylosanthes hamata. 1. Fertiliser and stocking rate effects." Australian Journal of Experimental Agriculture 33, no. 5 (1993): 561. http://dx.doi.org/10.1071/ea9930561.
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Native pastures dominated by Heteropogon contortus (speargrass) were sown to Stylosanthes hanzata cv. Verano in 1972, and herbage production and steer growth rates were compared with those of native pastures from 1973 to 1985. The native pastures also contained naturalised Stylosanthes humilis, but its contribution to pasture yield diminished rapidly, after infection by Colletotrichum gloeospoirioides (anthracnose) in 1973. The experiment was a factorial design of 2 pasture types (native, native plus Verano) x 2 stocking rates (0.6, 1.2 steers/ha) x 2 superphosphate treatments (nil, 300 kg/ha.year) x 2 replicates. Fertiliser application decreased the proportion of legume but had no significant effect on herbage or animal production on this comparatively fertile site (extractable P, 18 mg/kg). Annual liveweight gains at the high and low stocking rates, respectively, on the native pasture averaged 100 and 120 kg/steer. Sowing to Verano did not affect herbage yields but increased annual liveweight gains by 28 and 36 kg/steer at low and high stocking rates. The high stocking rate of 1.2 steers/ha was sustainable for the first 9 years of the experiment, when above-average rainfall was received. However, in the following 3 below-average years, there was a shift to less-desirable species, and a decline in pasture productivity. Relative to the low stocking rate, herbage production on the native pasture in the final season was reduced by 60% and on the Verano pasture by 26%. The highest annual herbage utilisation rate that appeared sustainable in the long term was about 45%, which corresponded to a utilisation rate of 30% during the growing season (about November-May). When oversown with Verano, speargrass tended to decline in favour of annual grasses, weeds, and the introduced grass Urochloa mosanzhicensis, which had been sown on an adjacent experiment. Urochloa appeared to be a more suitable companion species than speargrass for Verano.
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Lodge, G. M. "Studies of soil seedbanks in native and sown pastures in northern New South Wales." Rangeland Journal 23, no. 2 (2001): 204. http://dx.doi.org/10.1071/rj01007.
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Total and germinable soil seedbanks (litter and soil) were studied for a native pasture and three sown pastures (dominated by Phalaris aquatica L. cv. Sirosa) in northern New South Wales from 1993 to 1996. Soil core samples were taken from continuously grazed plots for both pasture types and two oversown treatments in the native pasture and from a spring-autumn rest treatment at the sown pasture sites. At each site above ground herbage mass was also estimated regularly as part of the Temperate Pasture Sustainability Key Program. For all sites and treatments, the proportion of germinable seeds as a percentage of the total (dormant and germinable) seedbank ranged from 1–26% for the native pasture and 1–39% for the sown pastures. Germinable seed numbers ranged from 280 to 26,110 seeds per m2, while total seedbank numbers were from 6700 to 178,360 seeds per m2. Native pasture herbage mass was dominated by native perennial grasses, but seeds of these species were less than 20% of the total seed bank in all treatments in 1994 and 1995. At the sown pasture sites, most of the germinable (51–92%) and total (65–97%) seedbanks were either barnyard grass (Echinochloa crus-galli (L.) Beauv, annual ryegrass (Lolium rigidum Gaudin), subterranean clover (Trifolium subterraneum L.) or wireweed (Polygonum aviculare L.). Since seeds of annuals and other forbs generally dominated both the total and germinable seedbanks of these perennial grass-based pastures, these species were likely to increase over time. Seeds of the sown perennial grass Phalaris aquatica L, cv. Sirosa were less than 1% of the total seedbanks in pastures sown in 1990 and less than 3% of those sown in 1979. With above average summer rainfall at the native pasture site in 1996 and prolific growth of redgrass, seeds of this species were 38–63% of the total and 11–29% of the germinable seedbank in May 1996. Except at this site and time, the species composition of the total and germinable seedbanks did not generally reflect the dominance of the above ground herbage mass of these pastures by perennial grasses.
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Vere, D. T., R. E. Jones, and M. H. Campbell. "Long-term change in the economic productivity of four major pasture categories on the south-eastern Tablelands of New South Wales." Rangeland Journal 23, no. 2 (2001): 148. http://dx.doi.org/10.1071/rj01002.
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The perception of change or decline in the productivity of temperate pastures in south-eastern Australia is an important concern to livestock producers and pasture scientists. Much of this concern relates to reductions in the proportions of desirable species in the composition of pasture systems as a result of increased soil and weed problems. The purpose of this paper is to investigate trends in the long-term economic productivity of four categories of temperate pastures (all introduced pastures, introduced perennial grasses, introduced legumes and all native pastures) on the central and southern tablelands of New South Wales. The results provide evidence of economic productivity decline in the all introduced pastures category in relation to sheep production, but this has been due to productivity decline in the dominant legume component of the introduced pastures. In contrast, there has been strong growth in the economic productivity of the introduced perennial grass pastures. Abnormally high beef cattle numbers in the mid-1970s appear to have created an illusion of high productivity and subsequent decline in all introduced pastures. In contrast, the economic productivity of the native pastures which are the bulk of the region's grazing areas, has fallen substantially.
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CASTELÁN-ORTEGA, O. A., C. G. MARTÍNEZ-GARCÍA, F. L. MOULD, P. DORWARD, G. C. MIRANDA-DE LA LAMA, ROSY GABRIELA CRUZ-MONTERROSA, and A. A. RAYAS-AMOR. "GRAZING BEHAVIOUR OF DAIRY COWS AND BODY CONDITION SCORE ASSOCIATED WITH SWARD CHARACTERISTICS OF FOUR PASTURE TYPES." Experimental Agriculture 54, no. 2 (March 14, 2016): 214–26. http://dx.doi.org/10.1017/s001447971600020x.
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SUMMARYThe objectives were to assess the following: (1) the relationship between sward height and chemical composition of four pasture types in association with grazing behaviour and body condition score (BCS) of dairy cows, and (2) the possibility of developing predictive equations of the nutrient intake and grazing behaviour within a continued grazing system. Pasture type had a significant (p < 0.01) effect on nutrient supply from January to June for all pastures investigated. Ryegrass–white clover pasture (RW) had the highest metabolizable protein and metabolizable energy, followed by kikuyu pasture (KP), which was significantly (p < 0.001) higher than native pastures 1 and 2 (NP1 and NP2). The highest values for effective grazing time, bite rate and BCS were found when dairy cows grazed RW followed by KP, NP2 and NP1. The results suggested that pasture type and sward height influenced grazing behaviour and BCS of dairy cows during the dry season. In the same vein, RW showed higher effective grazing time, bite rate, nutrient intake and BCS than the other three pastures suggesting that RW pastures that appear to be more expensive than native pastures could result in superior cow performance.
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Brenner, Jacob C., and L. Leann Kanda. "Buffelgrass (Pennisetum ciliare) Invades Lands Surrounding Cultivated Pastures in Sonora, Mexico." Invasive Plant Science and Management 6, no. 1 (March 2013): 187–95. http://dx.doi.org/10.1614/ipsm-d-12-00047.1.
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AbstractWe examined relationships between land disturbance and the extent and abundance of exotic buffelgrass (Pennisetum ciliare) at the interface of cultivated pastures and native desert lands in Sonora, Mexico. Plot and transect surveys of lands inside and outside pasture fences and general linear mixed models revealed complex relationships among buffelgrass, native vegetation, distance from pasture fences, and three categories of land disturbance (undisturbed, moderate, and severe). Results illustrate that buffelgrass invasion is extensive in lands surrounding pastures, and that buffelgrass abundance declines steeply with distance from pasture fences. The role of disturbance is weak but significant in its interaction with distance from the fence. Buffelgrass is more successful at colonizing severely disturbed lands than native vegetation, and its decline in abundance on severely disturbed lands is relatively more gradual than on other disturbance regimes, so landscapes where severely disturbed lands are interspersed with buffelgrass pastures could become centers of extensive buffelgrass invasion. In light of its potential to transform the Sonoran Desert, buffelgrass outside pastures warrants attention in a region-wide control scheme, as well as in future research, which ideally would involve remote sensing.
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Schwenke, G. D., M. K. McLeod, S. R. Murphy, S. Harden, A. L. Cowie, and V. E. Lonergan. "The potential for sown tropical perennial grass pastures to improve soil organic carbon in the North-West Slopes and Plains of New South Wales." Soil Research 51, no. 8 (2013): 726. http://dx.doi.org/10.1071/sr13200.
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Sown tropical perennial grass pastures may be a means to restore soil organic carbon (C) lost by cropping with conventional tillage to the levels originally present in native grass pastures. To assess this, total organic carbon and related soil properties were measured under sown tropical pastures, conventionally cultivated cropping, and native pastures on 75 Chromosols and 70 Vertosols to 0.3 m depth in the New South Wales North-West Slopes and Plains region of Australia. The impact of several perennial pasture species on soil organic carbon was also assessed in a 6-year-old, sown pasture experiment on a previously cropped Chromosol. Soil cores in 0.1-m segments to 0.3 m were analysed for total organic carbon, total nitrogen (N), pH, and phosphorus (Colwell-P). Mid-infrared scans were used to predict the particulate, humus, and resistant fractions of the total organic carbon. Bulk density was used to calculate stocks of C, N, and C fractions. In Chromosols, total organic carbon in the surface 0–0.1 m was greater under sown tropical pastures (23.1 Mg ha–1) than conventional tillage cropping (17.7 Mg ha–1), but still less than under native pastures (26.3 Mg ha–1). Similar land-use differences were seen for particulate and resistant organic C, and total N. The proportional differences between land uses were much greater for particulate organic C than other measures, and were also significant at 0.1–0.2 and 0.2–0.3 m. Subsurface bulk density (0.1–0.2 m) was lower under sown tropical pastures (1.42 Mg m–3) than conventionally tilled cropping (1.52 Mg m–3). For Vertosols, total organic carbon in the surface 0–0.1 m was greater under sown tropical pastures (19.0 Mg ha–1) and native pastures (20.5 Mg ha–1) than conventional tillage cropping (14.0 Mg ha–1). Similar land-use effects were seen for the particulate and humus organic C fractions, and total N. In the sown pasture species experiment, there was no significant difference in total N, total organic carbon, or any C fraction between soils under a native-grass species mixture, two improved tropical grass species, or a perennial pasture legume. Regular monitoring is required to better discern whether gradual changes are being masked by spatial and temporal variation. The survey results support previous research on Vertosols within the New South Wales North-West Slopes and Plains that show sown tropical grass pastures can improve total organic carbon. Improvements in total organic carbon on Chromosols have not previously been documented, so further targeted soil monitoring and experimentation is warranted for the region.
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McIntyre, S., K. M. Heard, and T. G. Martin. "How grassland plants are distributed over five human-created habitats typical of eucalypt woodlands in a variegated landscape." Pacific Conservation Biology 7, no. 4 (2001): 274. http://dx.doi.org/10.1071/pc020274.
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A sample of 212 quadrats in grassland vegetation was collected in eucalypt woodlands in sub-tropical Queensland. These included roadside (53 sites), native pasture (109), riparian zone (20), sown pasture (16) and crop (14) habitats. A total of 350 species and subspecies was recorded of which 89 species were identified as being locally rare (native species of <3% frequency, not specialists of other habitats). Forty-three species were collected in addition to the quadrat records. Multivariate analysis indicated the major difference in floristic composition was between roadsides and native pastures, versus the other three habitats. The second axis separated roadside from native pasture vegetation, and the third axis separated riparian sites from all the rest. Crop and sown pasture habitats were the most similar in composition. The grazing practices in this region have enabled the persistence of grasslands that are of national significance in conservation terms. The variegated nature of the landscape is demonstrated by the occurrence of native grassland species across all the human-created habitats, including native species that were unique to intensive land uses. However, our results also show that intensive land uses (cropping, sown pastures) are more of a threat to the conservation status of grasslands than is cattle grazing, even at commercial levels of stocking. Species at most immediate risk are those that are sensitive to commercial cattle grazing and to intensive land uses such as crops and sown pastures.
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Hendricksen, RE, JH Ternouth, and LD Punter. "Seasonal nutrient intake and phosphorus kinetics of grazing steers in northern Australia." Australian Journal of Agricultural Research 45, no. 8 (1994): 1817. http://dx.doi.org/10.1071/ar9941817.
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The growth of Bos indicus cross-steers grazing native grass and native grass-legume (Stylosanthes scabra cv. Seca) pastures was monitored for 392 days in five unreplicated experimental paddocks, each grazed by three steers. Two phosphorus (P) fertilizer rates: F1, 4-5 kgP/ha every 2 years and F2, 9.0 kgP/ha annually, together with an unfertilized control, FO, were studied. P supplement was supplied to cattle in two additional paddocks (FOS and F1S) at the rate of 5 gP/ha/day-l. In the dry, wet and late wet seasons, pasture yield and pasture component yield were measured. At the same time, the nutrient intake and P kinetics of resident steers were measured using chromic oxide capsules and intravenous injections of 32P . Additional non-resident steers, fistulated at the oesophagus, grazed the pastures intermittently to provide estimates of dry matter digestibility, fibre, nitrogen (N) and P content of the selected diet. Phosphorus fertilizer increased legume and native grass growth which resulted in more dry matter containing higher concentrations of P and N than unfertilized pastures. Both P fertilizer and supplement increased dry matter intake and liveweight gain of cattle. During the experimental period of 13 months, steers which grazed pastures that received the (F2) fertilizer treatment gained on average 0.43 kg/day compared with 0.19 kg/day for those which grazed unfertilized FO pastures. Supplementation increased wet season liveweight gain from 0.45 to 0.59 kg/day and 0.46 to 0.73 kg/day for FO and F1 treatments respectively. Only cattle which grazed pastures that received the F1S and F2 treatments gained weight in the dry season. Nitrogen was the primary nutrient limiting cattle growth from unfertilized pastures in the dry season, but when pastures were fertilized (4.5 kgP/ha every 2 years) and legumes established, P was the primary limiting nutrient. Intakes of P ranged from 7 to 35 mg/kg LW and were lower than those recommended by recognized authorities for the steer growth rates we recorded. Both the absorption and faecal excretion of dietary P were closely related to P intake. Endogenous faecal P values varied with P intake in the range 9-22 mg/kg liveweight. Endogenous faecal P was also related to dry matter intake and plasma inorganic P. The coefficient of P absorption was lowest (0.65) for steers grazing unfertilized native pasture (FO), but increased with P intake to 0.85 for steers grazing the F1S treatment. We conclude that the P requirements of growing cattle grazing native grass and native grass-legume pastures in northern Australia are about half those recommended by most authorities.
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Vickery, P. J., M. J. Hill, and G. E. Donald. "Satellite derived maps of pasture growth status: association of classification with botanical composition." Australian Journal of Experimental Agriculture 37, no. 5 (1997): 547. http://dx.doi.org/10.1071/ea97014.
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Summary. Spectral data from the green, red and near-infrared bands of Landsat MSS and Landsat TM satellite imagery acquired in mid-spring were classified into 3 and 6 pasture growth classes respectively. The classifications were compared with a site database of botanical composition for the Northern Tablelands of New South Wales to examine the association between spectral growth class and pasture composition. Pastures ranged in composition from unimproved native perennial grasses through semi-improved mixtures of native and naturalised grasses and legumes to highly improved temperate perennial grasses and legumes. For 3 years of MSS data, the fast growth class had a mean botanical composition of about 80% improved perennial grass and 0% native; medium growth class averaged 46% improved perennial grass and 14% native; while the slow growth class had about 60% native and 1% improved perennial grass when averaged over 3 years of MSS data. For the 6 class TM data from a single year, a predictive logistic regression of cumulative probability was developed for percentage of ‘very fast’ growth pixels and ordered 10 percentile categories of improved perennial grass or native grass. Differences in patch characteristics between classes with MSS disappeared with TM reclassified to the same 3 class level. Most probable pasture type was inferred from 3 class MSS and TM data using Bayesian probability analysis. The resulting maps were similar in general appearance but detail was better with the TM data. The pasture growth classification identified highly improved perennial grass pastures and native pastures but sensitivity to intermediate pasture types was poor. Future improvement will come from direct measurement of biophysical characteristics using vegetation indices or inversion of reflectance models.
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McIvor, JG, and CJ Gardener. "Germinable soil seed banks in native pastures in north-eastern Australia." Australian Journal of Experimental Agriculture 34, no. 8 (1994): 1113. http://dx.doi.org/10.1071/ea9941113.
Full textAbstract:
Germinable soil seed banks were determined in 20 native pasture communities of widely varying composition (dominated by native tussock grasses, Bothriochloa pertusa, or forbs) near Collinsville (20�34'S, 147�51'E). Samples of surface soil (0-10 cm) were taken during the late dry season, seeds were germinated in a shadehouse, and seedlings were identified and counted. Over all pastures there were seeds of 100 species in the seed banks, including 29 grasses (14 perennial), 11 legumes, 8 sedges, and 52 forbs. Total seed numbers varied among pastures from 210 to 9770/m2. Forbs were the most numerous component, followed in order by sedges, perennial grasses, annual grasses, and legumes. Of the 790 seeds/m2 of perennial grasses, the naturalised species B. pertusa contributed 620/m2. Even though the native perennial grasses were prominent in these pastures, they had few seeds in the soil, especially when the pastures had been heavily grazed. To maintain these grasses in pastures, management should aim to prevent excessive mortality of the perennial plants as seedling regeneration could be limited by the small seed numbers available.
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Tozer, K. N., R. H. Bryant, C. A. Cameron, and G. R. Edwards. "Survey of ripgut brome and other species on Canterbury hill/high country roadsides." New Zealand Plant Protection 66 (January 8, 2013): 105–9. http://dx.doi.org/10.30843/nzpp.2013.66.5716.
Full textAbstract:
Ripgut brome is found in high country Canterbury pastures but little is known of its prevalence and distribution In a 1020 km roadside vegetation survey all exotic and native plant species within a 5 m 5 m quadrat were identified at 10 km intervals Ripgut brome (Bromus diandrus) was present in 11 of the 165 quadrats which ranged from 40 to 950 m above sea level occurring most frequently below 200 m It was least often detected adjacent to intensive pastures (only 2 of quadrats) Agrostis capillaries (browntop) was present in 63 of quadrats followed by Trifolium repens (white clover 59) and Dactylis glomerata (cocksfoot 53) The lowest number of exotic species was detected adjacent to intensive pasture (58) and highest adjacent to forestry (86 species) Highest numbers of native species were present adjacent to semiimproved pastures (17) and above 500 m (23 species) Species prevalent on roadsides were commonly grazed in hill/high country pastures rather than being pasture weeds
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Tarawali, S. A., and M. Peters. "The potential contribution of selected forage legume pastures to cereal production in crop-livestock farming systems." Journal of Agricultural Science 127, no. 2 (September 1996): 175–82. http://dx.doi.org/10.1017/s0021859600077959.
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SUMMARYThe potential of 3-year-old grazed pastures ofStylosanthes hamata, Chamaecrista rotundifoliaandCentrosema pascuorumto contribute to subsequent maize production was investigated in subhumid Nigeria in 1993. All three legume pastures had the ability to give better maize grain yields than native pasture but this was significant only forStylosanthes hamataandChamaecrista rotundifolia. For the legume species, maximum yield of maize per kg of N applied was attained at 60 kgN/ha. The subsequent yields of maize could be related to the legume species used, pasture management and the length of the fallow period.Centrosema pascuorumbehaved as an annual, and as such there was little legume present after 3 years; crop yield was therefore relatively low. Nevertheless, this species could be useful in 1-year fallow/pasture situations. Maize cropping was economically viable for legume plots only with 60 or 120 kgN/ha and not for native pasture. There were no significant differences in the time required to till or to weed legume pastures as compared with native pasture. Forage legume pastures could also have a positive effect on maize residue yields which represent a fodder resource in addition to the herbage understorey remaining after cropping, the quality of which could be enhanced by the presence of the forage legumes. The use of forage legumes for the promotion of both crop and livestock production in sustainable agricultural systems is discussed. The results of the study are used to highlight the importance of selecting the appropriate legume species, pasture management practices and duration of fallow period in relation to the prevailing farming system to maximize benefits from the legumes.
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McIvor, J. G. "Pasture management in semi-arid tropical woodlands: regeneration of degraded pastures protected from grazing." Australian Journal of Experimental Agriculture 41, no. 4 (2001): 487. http://dx.doi.org/10.1071/ea00045.
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Regeneration of native and oversown pastures following exclusion of grazing was studied over 3 years on a fertile soil at Hillgrove, near Charters Towers, north-east Queensland. The pastures covered a wide range of initial conditions reflecting the grazing pressures they had been exposed to during 2 dry years before enclosure. Pasture measurements made before the exclusion of grazing (yield, botanical composition, basal area, ground cover, height, soil seed banks) were related by regression analysis to subsequent changes in site condition described by a site condition value, calculated from herbage yields and botanical composition, to determine suitable predictors of regeneration during resting from grazing. The pastures recovered (increases in soil cover, grass basal area and the proportion of desirable species) under the generally favourable growing conditions during the period of enclosure although some plots, initially in poor condition, had not recovered after 3 years. There were only minor differences between the native and oversown pasture types in their recovery. Relative yields and site condition values were not affected by pasture type and botanical composition index values differed with pasture type in 1989 only. The site condition values of both pasture types after the first year of enclosure were closely and positively related to all the pasture characteristics measured the previous year except for soil seed numbers in the native pastures. All characteristics could be used to predict site condition value and potential of the pasture to regenerate, and their merits are discussed. The proportion of desirable species in the pasture combined with level of ground cover is suggested as a useful means of predicting regeneration and potential for future grazing.
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Norton, BW, and MJ Deery. "The productivity of Angora goats grazing improved and native pastures in south-eastern Queensland." Australian Journal of Experimental Agriculture 25, no. 1 (1985): 35. http://dx.doi.org/10.1071/ea9850035.
Full textAbstract:
Two groups of Angora wether goats were grazed over 1 year on replicated areas (0.4 ha each) of either pure N-fertilized Pangola grass (Digitaria decumbens Stent.) pasture or native pastures containing Acacia, Eucalyptus and groundsel (Baccharis halimfolia L.) regrowth. Half of the goats in each group were given a cobalt bullet and their health, liveweight change and fleece growth were monitored. When adequate levels of native pasture were available (>800 kg green matter/ha) performance of goats on the different pastures was similar over the spring and summer grazing periods. In the winter period, fleece growth rate and yield were significantly (P<0.05) lower and liveweight loss (11 g/day) occurred in goats grazing native pastures. In the same period, goats on Pangola grass pastures supplemented with cobalt continued to grow (39 g/day) and maintained high fleece yields while unsupplemented goats on the same area lost weight rapidly (84 g/day), indicating the onset of cobalt deficiency. Over a 9-month period, the population of regrowth acacias and eucalypts less than 1.5 m high were markedly reduced, and groundsel was completely eliminated from the area. In this period, the palatable native grasses were selected in preference to blady grass (Imperata cylindrica (L.) Beauv.), which increased as a proportion of declining total grass yield.
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Hall, Trevor J., Richard G. Silcock, and David G. Mayer. "Grazing pressure and tree competition affect cattle performance and native pastures in Eucalypt woodlands of Queensland, north-eastern Australia." Animal Production Science 60, no. 7 (2020): 953. http://dx.doi.org/10.1071/an18512.
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Context Well managed grazing pressure will optimise animal and pasture production, and preserve the soil to maintain a viable beef business on native pastures in eucalypt woodlands. Aims A cattle grazing experiment was established to measure animal and pasture performance under management practices used in the Aristida/Bothriochloa native pastures in central Queensland. Methods Performance of Brahman-cross steers and pastures were measured in an experiment with three grazing pressures by two tree densities in a Eucalyptus populnea woodland in north-eastern Australia over 8 years in paddocks of 4–18 ha. Key results At low grazing pressure with trees killed by herbicide (‘cleared’), stocking rate increased 35% as pasture composition and biomass improved over 8 years. At low grazing pressure where treed, stocking rate remained constant, however, at high grazing pressure where treed, it was reduced after 4 years. The annual liveweight gain increased from 0.37 to 0.45 to 0.51 kg/head.day as grazing pressure was reduced from high to medium to low grazing pressure respectively, and across grazing pressures it decreased from 0.49 where cleared to 0.39 kg/head.day where treed. Liveweight gain per hectare increased under low grazing pressure and declined at medium and high pressures. Body condition scores responded positively to lower grazing pressure and a lack of tree competition to pastures. This treatment combination also produced higher animal sale values. Pasture biomass, basal area and ground cover were all affected negatively by increasing grazing pressure. Conclusions Grazing 25% of autumn pasture improved dry matter production, species composition and land condition, and increased steer growth rates, body condition and their market value. This grazing pressure produced an increasing trend in stocking rates relative to the decline at higher grazing pressures. Higher liveweight gain/ha was produced initially at high grazing pressure (75% utilisation), however, after 4 years animal condition and pastures deteriorated, requiring a reduction in stocking rate to maintain the condition of both the remaining animals and the pastures. Managing tree competition to pastures is necessary to maintain the higher animal production potential. Implications This objective information demonstrates the benefits for cattle, pastures and long-term economic outcomes of managing for conservative grazing pressure and controlling tree competition to pasture in this woodland. Applying these findings can improve beef business outcomes and provide management groups with objective educational resources.
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Murray, A. H., D. Daalkhaijav, and C. D. Wood. "Rumen degradability of Mongolian pastures: a comparison of in situ and in vitro gas production techniques." Proceedings of the British Society of Animal Science 1996 (March 1996): 227. http://dx.doi.org/10.1017/s0308229600031901.
Full textAbstract:
In Mongolia animal performance is very much dependent on the quality and quantity of natural grassland available, since certain pastoral animals may obtain as much as 98% of their annual intake from pasture. There have been few studies to date on either in vivo or in vitro degradation of native Mongolian pastures. This paper seeks to investigate the degradation characteristics of native pastures from 2 regions in Mongolia, high mountain and forest steppe. It also investigates the relationship between the in vitro gas production technique and the in sacco technique.
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Garden, D. L., G. M. Lodge, D. A. Friend, P. M. Dowling, and B. A. Orchard. "Effects of grazing management on botanical composition of native grass-based pastures in temperate south-east Australia." Australian Journal of Experimental Agriculture 40, no. 2 (2000): 225. http://dx.doi.org/10.1071/ea98010.
Full textAbstract:
Grazing management strategies to alter botanical composition of native pastures were investigated at 4 locations in the high rainfall zone of south-east Australia, including Tasmania. These studies were conducted as part of the Temperate Pasture Sustainability Key Program, which evaluated the effects of grazing management on a wide range of pasture types between 1993 and 1996. Pastures in this study were based on Aristida ramosa/Bothriochloa macra, Microlaena stipoides–Austrodanthonia spp. or Themeda triandra–Austrodanthonia spp. Seasonal rests, increased grazing pressure in spring, mob stocking and cutting for hay were compared to continuous grazing at all sites. In addition, specific local treatments were tested at individual sites. Changes in composition resulting from the treatments were minimal at most sites. This may have been due to a combination of the inherent stability of the pastures, the relatively short duration of the experiments, and the drought conditions experienced, which minimised differences between treatments. Some strategies to alter composition of natural pastures are suggested. In the Aristida–Bothriochloa pasture there was a general decrease in Aristida and an increase in Bothriochloa, which was largely unaffected by the type of grazing management applied. The combination of drought conditions and increasing grazing pressure was sufficient to alter composition without specific management strategies being necessary. In the Themeda–Austrodanthonia pasture, resting in spring, 12-month rests or cutting for hay (which involved a spring rest) allowed Themeda to increase in the pasture. The Microlaena–Austrodanthonia pastures were very stable, especially where annual grass content was low. However, certain treatments allowed Microlaena to increase, a result which is regarded as being favourable. The major effects in these latter pastures were on undesirable species. Vulpia spp. were reduced by resting in autumn and increased spring grazing pressure, while Holcus lanatus was increased dramatically by resting in spring and was also increased by resting in autumn or winter, but only when conditions were suitable for growth of this species. In many cases, treatment differences were only expressed following recovery from drought, showing that timing of grazing management to achieve change is critical.
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Petit, Hélène V. "Pasture management and animal production in Quebec: A review." Canadian Journal of Animal Science 73, no. 4 (December 1, 1993): 715–24. http://dx.doi.org/10.4141/cjas93-077.
Full textAbstract:
Twenty percent of forage farmland was devoted to seeded and native pastures in 1991. Common white clover is widely found in native pastures but ladino clover is the main legume recommended. Timothy is the most popular grass for seeded pasture and its yield is increased by N fertilization. More than 30% ladino in pasture decreases the N fertilizer requirement. High fertilization of pasture where beef steers are kept at high stocking rates and moderately fertilized pasture where beef steers are kept at low stocking rates result in similar average daily gains. Excessive steer stocking rates can result in decreased herbage production at the end of the growing season which results in decreased weight gain. However, feeding concentrate can compensate for herbage shortage and maintain weight gain of steers with a high stocking rate similar to that of unsupplemented animals on pasture with a low stocking rate. The difference in total beef production per hectare between heavily and moderately fertilized pastures is only 10% higher for the former when herbage surpluses conserved as silage and hay are fed to steers during winter. When herbage allowance is not limiting, there appears to be no advantage in supplementing grazing cattle with concentrate or protein. Key words: Pasture, grazing, dairy cattle, beef cattle, sheep
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Silcock, R. G., T. J. Hall, P. G. Filet, A. M. Kelly, D. Osten, C. M. Schefe, and P. T. Knights. "Floristic composition and pasture condition of Aristida/Bothriochloa pastures in central Queensland. I. Pasture floristics." Rangeland Journal 37, no. 2 (2015): 199. http://dx.doi.org/10.1071/rj14106.
Full textAbstract:
A survey was conducted in central inland Queensland, Australia of 108 sites that were deemed to contain Aristida/Bothriochloa native pastures to quantitatively describe the pastures and attempt to delineate possible sub-types. The pastures were described in terms of their floristic composition, plant density and crown cover. There were generally ~20 (range 5–33) main pasture species at a site. A single dominant perennial grass was rare with three to six prominent species the norm. Chrysopogon fallax (golden-beard grass) was the perennial grass most consistently found in all pastures whereas Aristida calycina (dark wiregrass), Enneapogon spp. (bottlewasher grasses), Brunoniella australis (blue trumpet) and Panicum effusum (hairy panic) were all regularly present. The pastures did not readily separate into broad floristic sub-groups, but three groups that landholders could recognise from a combination of the dominant tree and soil type were identified. The three groups were Eucalyptus crebra (narrow-leaved ironbark), E. melanophloia (silver-leaved ironbark) and E. populnea (poplar box). The pastures of the three main sub-groups were then characterised by the prominent presence, singly or in combination, of Bothriochloa ewartiana (desert bluegrass), Eremochloa bimaculata (poverty grass), Bothriochloa decipiens (pitted bluegrass) or Heteropogon contortus (black speargrass). The poplar box group had the greatest diversity of prominent grasses whereas the narrow-leaved ironbark group had the least. Non-native Cenchrus ciliaris (buffel grass) and Melinis repens (red Natal grass) were generally present at low densities. Describing pastures in terms of frequency of a few species or species groups sometimes failed to capture the true nature of the pasture but plant abundance for most species, as density, herbage mass of dry matter or plant crown cover, was correlated with its recorded frequency. A quantitative description of an average pasture in fair condition is provided but it was not possible to explain why some species often occur together or fail to co-exist in Aristida/Bothriochloa pastures, for example C. ciliaris and E. bimaculata rarely co-exist whereas Tragus australianus (small burrgrass) and Enneapogon spp. are frequently recorded together. Most crown cover was provided by perennial grasses but many of these are Aristida spp. (wiregrasses) and not regarded as useful forage for livestock. No new or improved categorisation of the great variation evident in the Aristida/Bothriochloa native pasture type can be given despite the much improved detail provided of the floristic composition by this survey.
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Lodge, G. M., and S. R. Murphy. "Root depth of native and sown perennial grass-based pastures, North-West Slopes, New South Wales. 1. Estimates from cores and effects of grazing treatments." Australian Journal of Experimental Agriculture 46, no. 3 (2006): 337. http://dx.doi.org/10.1071/ea04276.
Full textAbstract:
Studies were undertaken on native and sown perennial grass-based pastures as part of the Sustainable Grazing Systems National Experiment to estimate root depth and describe root distribution in these pastures. Samples from soil cores (0–210 cm maximum sampling depth) taken in 1997 (before grazing treatments were imposed) and 4 years later in spring 2001 were used to examine the effects of different grazing regimes on root length density (cm/cm3), root mass density (mg/cm3), root volume density (cm3/cm3), and diameter (mm) at each of 3 sites. In spring 1997, mean maximum root depth was 107 cm for a native perennial grass pasture near Barraba and 74 cm for a pasture sown with phalaris (Phalaris aquatica) and subterranean clover (Trifolium subterraneum) near Nundle, with values being lower for a native pasture near Manilla (65 cm for a Brown Vertosol and 97 cm for a Red Chromosol). For all pasture types, >20% of root mass density, root length density or root volume density was in the 0–5 cm soil layer and >60% was at a depth of 0–30 cm. At all sites, mean total root mass was around 1000 kg DM/ha. After 4 years of grazing (spring 2001) there were relatively few significant effects of grazing treatment on root length density, root mass density, root volume density, or root diameter. Effects that were significant mostly occurred at 0–5 cm for the native pastures and 0–50 cm for the sown pasture. For the Barraba native pasture, root length, volume and mass densities (0–5 cm) were higher (P<0.05) in the continuously grazed, low stocking rate treatment compared with all other treatments. Similarly, for the Manilla native pasture, root length density was higher (P<0.05) in this treatment at soil depths of 0–5 and >5–10 cm compared with all other treatments. In contrast, for the Nundle sown pasture, root length density (0–5 cm) was lowest (P<0.05) in 2 continuously grazed treatments compared with those that were strategically grazed in autumn and spring.
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Pearson, C. J., R. Brown, W. J. Collins, K. A. Archer, M. S. Wood, C. Petersen, and B. Bootle. "An Australian temperate pastures database." Australian Journal of Agricultural Research 48, no. 4 (1997): 453. http://dx.doi.org/10.1071/a96095.
Full textAbstract:
A census of pasture types and their composition and attributes (e.g. purpose and carrying capacity) was carried out throughout southern Australia from June to October 1994. This paper describes the survey process and subsequent creation of an Australian temperate pastures database. Data were created for 562 local government areas (LGAs) from ‘desk estimates’ by trained agriculturists. They identified about 2500 pasture types, which were grouped into 120 standardised pasture categories. Some findings from the data are identified, namely the high relative importance on an area basis of unimproved native pastures, the importance of weedy species (e.g. Vulpia), and the marked decline with increasing rainfall in importance of annual medics compared with subterranean clover. This paper provides examples of the data and their use for assessment of the regional economic impact of increases in productivity of pasture species.
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Scarnecchia, David L., and Ian Partridge. "Managing Native Pastures. A Grazier's Guide." Journal of Range Management 47, no. 6 (November 1994): 505. http://dx.doi.org/10.2307/4003009.
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McKirdy, SJ, BA Coutts, and RAC Jones. "Occurrence of bean yellow mosaic virus in subterranean clover pastures and perennial native legumes." Australian Journal of Agricultural Research 45, no. 1 (1994): 183. http://dx.doi.org/10.1071/ar9940183.
Full textAbstract:
In 1990, infection with bean yellow mosaic virus (BYMV) was widespread in subterranean clover (Trifolium subterraneum) pastures in the south-west of Western Australia. When 100 leaves were sampled at random per pasture, the virus was detected by ELISA in 23 of 87 pastures and incidences of infection ranged from 1 to 64%. BYMV was present in all seven districts surveyed, but highest incidences of infection occurred in the Busselton district. In smaller surveys in 1989 and 1992, incidences of infection in pastures were higher than in 1990, and ranged up to 90%. In 1992, when petals from 1703 samples of 59 species of perennial native legumes from 117 sites were tested by ELISA, only 1% were found infected with BYMV. The infected samples came from 5/7 districts surveyed. Species found infected were Kennedia prostrata, K. coccinea, Hovea elliptica and H. pungens. Representative isolates of BYMV from subterranean clover and native legumes did not infect white clover systemically confirming that clover yellow vein virus (CYVV) was not involved. It was concluded that BYMV infection was present in many subterranean clover pastures, but normally at low incidences, except in epidemic years such as 1992. Also, perennial native legumes are unlikely to act as major reservoirs for reinfection of annual pastures each year. In areas of Australia with Mediterranean climates where perennial pastures are absent, persistence of the virus over summer is therefore by some other method than infection of perennials.
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Hall, Trevor J., Paul Jones, Richard G. Silcock, and Piet G. Filet. "Grazing pressure impacts on two Aristida/Bothriochloa native pasture communities of central Queensland." Rangeland Journal 39, no. 3 (2017): 227. http://dx.doi.org/10.1071/rj16126.
Full textAbstract:
Managing native pastures for sustainable and economic production requires a good understanding of grazing effects on pasture dynamics. The Aristida/Bothriochloa pastures of north-eastern Australia are important for cattle production but little data on grazing pressure impacts on pastures are available to guide management decisions of producers, for land management education programs, or for predictive modelling. To address this deficiency, four different continuous grazing intensities were imposed on woodland communities over 7 or 8 years at two sites: a Eucalyptus populnea (poplar box) and a E. melanophloia (silver-leaved ironbark) community. Both sites had replicated paddocks grazed at a low, medium or high grazing pressure by +/− tree killing using herbicide (12 paddocks), and 12 ungrazed (nil grazing pressure) 1-ha plots subjected to the same tree-killing contrasts. Grazed paddock areas were fixed and varied between 3.5 and 21.5 ha. Differential grazing pressures were reset each autumn, by adjusting cattle numbers to consume over the next year the equivalent of 0%, 25%, 50% or 75% of the standing pasture mass available. Pasture grasses suitable as indicators of grazing pressure were identified for both communities. Under low grazing pressure, Themeda triandra (kangaroo grass) was the only desirable grass to show a significant increase in total contribution over time at both sites, although Dichanthium sericeum (Queensland bluegrass) also increased its contribution at the poplar box site. Chloris species increased their contribution as grazing pressure increased. The proportion of less palatable Aristida spp. (wiregrasses) in the pasture was not affected by high grazing pressure, although they increased at low grazing pressure in the poplar box community. There were no consistent changes in native legumes or weedy forb species to any treatment. Increasing grazing pressure had a greater negative effect on pasture mass, ground cover and pasture crown cover area than on changing species composition. Most changes in composition due to grazing pressure were smaller than those associated with variable seasonal rainfall, and were greater in the poplar box community. In above-average rainfall years grazing up to 50% of autumn standing pasture mass had no detrimental effect on composition in treeless poplar box country in the short term. The pastures remained stable or improved in both communities when grazing pressure was set annually to utilise 25% of the standing autumn forage.
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Garden, D. L., P. M. Dowling, D. A. Eddy, and H. I. Nicol. "A survey of farms on the Central, Southern and Monaro Tablelands of New South Wales: management practices, farmer knowledge of native grasses, and extent of native grass areas." Australian Journal of Experimental Agriculture 40, no. 8 (2000): 1081. http://dx.doi.org/10.1071/ea98157.
Full textAbstract:
Results are presented of a survey of pastoral properties on the Central, Southern and Monaro Tablelands of New South Wales carried out during 1991—92. Landholders were interviewed to obtain information on property size, enterprise types, grazing management, tree clearing, fertiliser history and carrying capacity. In addition, familiarity with native grass species, and knowledge of their value were determined. The main grazing enterprises were wool and beef. The most common form of livestock management was continuous grazing. Most properties had been extensively cleared of trees (average cleared area 80%), and there had been a significant amount of disturbance of the original pastures. This varied from 40% of total property area for the Central and Monaro Tablelands to 60% for the Southern Tablelands. The main form of disturbance was cultivation for pasture sowing or fodder cropping. Landholders had used 80% more fertiliser on disturbed areas than on undisturbed areas, with most fertiliser applied on the Southern Tablelands and least on the Monaro Tablelands. The average carrying capacities of undisturbed and disturbed pastures over the tablelands were 4.3 and 7.7 dry sheep equivalents per hectare, respectively. While most landholders were satisfied with the performance of their sown pastures, there was a lack of knowledge of the contribution of native perennial grasses to pasture production. Using survey data, it was estimated that pastures with native grasses as the major components covered a minimum of 1.38 million hectares or 40% of the surveyed area. With such a large contribution to production, there is a need to assist landholders to identify native perennial grasses so that their potential value can be more fully realised.
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Jones, R. J. "Steer gains, pasture yield and pasture composition on native pasture and on native pasture oversown with Indian couch (Bothriochloa pertusa) at three stocking rates." Australian Journal of Experimental Agriculture 37, no. 7 (1997): 755. http://dx.doi.org/10.1071/ea97032.
Full textAbstract:
Summary. Pasture production and steer liveweight gain were compared on native pasture (Bothriochloa decipiens, Heteropogon contortus, Themeda triandra and Chrysopogon fallax) and on native pasture oversown with Indian couch or Indian bluegrass (Bothriochloa pertusa). This grass was not a planned introduction to the area but is spreading in Central and North Queensland and its value as a pasture species is questioned by graziers. There were 3 nominal stocking rates of 0.3, 0.6 and 0.9 steers/ha. Each paddock was stocked with 3 steers of stratified ages. The experiment was sown in March 1988 and terminated in June 1993. The experiment, sited 50 km south of Townsville in eucalypt woodland on a solodic-solodised-solonetz soil, was sown in March 1988 and terminated in June 1993. Increases in stocking rate resulted in a linear decline in both pasture yield (by 3–5 t/unit increase in stocking rate) and steer gains (by more than 100 kg/unit increase in stocking rate). Differences between pastures were apparent only at the medium and high stocking rates where, over time, Indian couch gave higher pasture yields and steer gains. Younger steers gained far more weight than older steers. Mean gains over 3 years were weaners 125 kg/year, yearlings 93 kg/year and 2-year-old steers 46 kg/year. Native pasture remained fairly stable botanically at the low stocking rate, but the tufted perennial grass species declined at both the medium and high stocking rates. Sowing Indian couch hastened the botanical changes due to stocking rate, and it became the dominant species at these higher stocking rates. At the low stocking rate, the contribution of Indian couch declined from initial values indicating that this is not an invasive species in the area at a low stocking rate. Contribution of Indian couch to pasture yield was linearly related to stocking rate. Nutritional quality of the Indian couch was similar to the other native perennial grasses though calcium concentration was higher. Increased steer gains were related to higher yield on Indian couch pastures at the higher stocking rates rather than to improved quality. Maximum liveweight gain/ha was achieved at about 0.6 steers/ha. Stocking at 0.9 steers/ha was not sustainable. Even at the low stocking rate, steers would need to spend about 2.8 years on the pastures after weaning to reach 500 kg liveweight. It was concluded that B. pertusa is a useful pasture grass in this environment giving steer gains equal to, or higher than, the gains from the native pasture which it replaced.
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Winter, WH, RL McCown, and D. Zuill. "Legume-based pasture options for the live cattle trade from the Australian semi-arid tropics." Australian Journal of Experimental Agriculture 36, no. 8 (1996): 947. http://dx.doi.org/10.1071/ea9960947.
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The extensive beef industry in the Northern Territory has been based almost exclusively upon native grass pastures for over a century. The recent development of an export trade for live cattle of specific age, weight and type, has increased returns over chilled manufacturing beef exports and has resulted in a demand for improved pastures that can support rapid growth of young cattle. This paper compares the potential of native grass pastures, legume ley pastures and permanent sown grass-legume pastures, in a range of configurations, to meet the market demand. Results of farming systems and sown pasture management experiments conducted at the Katherine Research Station are presented. Data from these experiments and other sources are used to explore options appropriate to the new market. Particular attention has been given to the time required for weaner steers to reach export target weights of 290-300 kg/head and the flexibility of systems to seasonal and animal variability. Permanent sown pastures are sustainable at stocking rates of about 2 steers/ha, but results indicate difficulty in maintaining legume dominance in the ley pastures, particularly if the cropping frequency is reduced. A proposal to use forage crops, rather than grain crops, to deplete soil nitrogen and reduce the incidence of weeds, is discussed. We recommend that ley pastures be retained as part of the management system, despite management difficulties, as they provide higher productivity and greater flexibility for farmers to meet the market requirements.
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Garden, Denys, Christine Jones, Doug Friend, Meredith Mitchell, and Peter Fairbrother. "Regional research on native grasses and native grass‐based pastures." New Zealand Journal of Agricultural Research 39, no. 4 (December 1996): 471–85. http://dx.doi.org/10.1080/00288233.1996.9513209.
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Winter, WH, JJ Mott, RW McLean, and D. Ratcliff. "Evaluation of management options for increasing the productivity of tropical savanna pastures. 1. Fertiliser." Australian Journal of Experimental Agriculture 29, no. 5 (1989): 613. http://dx.doi.org/10.1071/ea9890613.
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Options for increasing pasture and animal production from native perennial pastures comprising predominantly Themeda triandra, Chrysopogon fallax, Sehima nervosum and Sorghum plumosum were studied over 5 years at Katherine in the semi-arid tropics of north-western Australia. The pastures were augmented with either Stylosanthes humilis, S. hamata or a mixture of S. scabra and S. viscosa, either without fertiliser or with low inputs of superphosphate (100 kg/ha at establishment and 25 kg/ha annually), and with the trees either killed or left undisturbed. At each fertiliser level there were 3 stocking rates. Five years after sowing, only half of the pastures persisted, due to the poor productivity of the legumes and the inability of the native perennial grasses to tolerate high grazing pressure which was about 10-fold that for non-augmented native pasture. This effect was greater in the unfertilised treatments, where the legume contributed less to pasture yield, so that the sustainable stocking rate was only half of that for pastures fertilised with small amounts of superphosphate. When fertilised, stable pastures of nearly pure legume were obtained after 3-4 years at the highest stocking rate of 1 steer/ha. Fertiliser also (i) increased the nitrogen and sulfur concentrations of S. humilis and the perennial stylos S. scabra and S. viscosa, but lowered their concentrations in S. hamata, particularly in the early wet season; (ii) decreased nitrogen concentration in Chrysopogon fallax; and (iii) increased phosphorus and sulfur concentrations of all the perennial grasses. In general, fertiliser promoted higher liveweight gains of cattle during the wet season and lower losses during the dry season. In the fertilised treatments growth tended to be poorer at the highest stocking rate, particularly during the late dry and early wet seasons. This effect was attributed to spoilage of dry legume by the early rainfall and lack of grass in these treatments. We conclude that S. hamata, S. scabra and S. viscosa grow reasonably well in soils of low fertility, but the productivity of the legumes and of the cattle can be improved by small inputs of superphosphate. The mediocre growth of the cattle in all the treatments may have been due to the low levels of some nutrients, particularly phosphorus and sulfur, in these pastures.
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Whalley, R. D. B., D. A. Friend, P. Sanford, and M. L. Mitchell. "Evaluation of native and introduced grasses for low-input pastures in temperate Australia: rationale and scope." Rangeland Journal 27, no. 1 (2005): 1. http://dx.doi.org/10.1071/rj05004.
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The historical approach to pasture improvement in the high rainfall zone of temperate Australia has been to add introduced herbaceous legumes and to replace perennial native grasses with introduced species requiring high inputs of fertiliser for maintenance. The application of this high-input approach on land with low capability has lead to the loss of perennial grasses, erosion, soil acidification and increasing salinity on the lower slopes. This model of pasture improvement has not been successful on the margins of the wheat belt and in semi-arid regions. The Native and Low-input Grasses Network (NLIGN) was established in 1996 to coordinate research on grasses suitable for land with low capability and for semi-arid regions. The NLIGN multi-site evaluation project was initiated to test promising lines (accessions) of native and introduced grasses for low-input pastures at eight sites across southern Australia. The broad objective of the project was to identify native and/or introduced perennial grass lines that had possible commercial potential for low-input pastures. This objective was achieved in an initial 3-year evaluation phase, which began in 1998 and tested lines for persistence, production and palatability.
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Feltran-Barbieri, Rafael, and José Gustavo Féres. "Degraded pastures in Brazil: improving livestock production and forest restoration." Royal Society Open Science 8, no. 7 (July 2021): 201854. http://dx.doi.org/10.1098/rsos.201854.
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Degraded pasture is a major liability in Brazilian agriculture, but restoration and recovery efforts could turn this area into a new frontier to both agricultural yield expansion and forest restoration. Currently, rural properties with larger degraded pasture areas are associated with higher levels of technical inefficiency in Brazil. The recovery of 12 million ha of degraded pastures could generate an additional production of 17.7 million bovines while reducing the need for new agricultural land. Regional identification of degraded pastures would facilitate the targeting of agricultural extension and advisory services and rural credit efforts aimed at fostering pasture recovery. Since only 1% of Brazilian municipalities contain 25% of degraded pastures, focusing pasture recovery efforts on this small group of municipalities could generate considerable benefits. More efficient allocation of degraded and native pastures for meat production and forest restoration could provide land enough to fully comply with its Forest Code requirements, while adding 9 million heads to the cattle inventory. Degraded pasture recovery and restoration is a win–win strategy that could boost livestock husbandry and avoid deforestation in Brazil and has to be the priority strategy of agribusiness sector.
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DEL PINO, A., T. RODRÍGUEZ, and J. ANDIÓN. "Production improvement through phosphorus fertilization and legume introduction in grazed native pastures of Uruguay." Journal of Agricultural Science 154, no. 2 (November 3, 2015): 347–58. http://dx.doi.org/10.1017/s002185961500101x.
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SUMMARYThe objective of the current study was to quantify the response of pasture to phosphorus (P) fertilizer application and legume introduction, by measuring herbage yield, nitrogen (N) and P content, and weight gain of calves in native pastures of Uruguay. Quantitative relationships between pasture characteristics and post-weaning daily live weight gain (DLWG) were also examined. The treatments studied were native grassland (NG) and improved pasture, oversown withLotus corniculatusL. andTrifolium repensL. with annual applications of either 13 and 26 kg P/ha. From 1996 to 2001 the treatments were evaluated each year with a new group of calves. Total herbage yields of the oversown pastures were not always higher than NG in the initial years, but legume production increased, although without significant differences between P rates on legume or total yield. This was also reflected in the N and P status of the swards. In the last 2 years legume proportion had declined to <0·1, but total herbage yield was significantly higher in the improved pastures. The average DLWG over the 6 years of measurements were 0·319, 0·478 and 0·586 kg/day for NG, P1 and P2, respectively, with average total live weight gain increased 1·8- and 2·5-fold by the legume introduction and annual addition of 13 and 26 kg P/ha, respectively. The study demonstrated that the evaluation of pasture response to P application should not be limited to assessing forage yield increase. Phosphorus availability in the herbage was a better predictor of animal performance than pasture yield. The study highlights that the benefits of oversowing and fertilizer inputs are short-lived, as withholding of fertilizer in the last 2 years resulted in a loss of sown legumes and decline in animal production.
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Robinson, J. B., D. M. Silburn, D. Rattray, D. M. Freebairn, A. Biggs, D. McClymont, and N. Christodoulou. "Modelling shows that the high rates of deep drainage in parts of the Goondoola Basin in semi-arid Queensland can be reduced with changes to the farming systems." Soil Research 48, no. 1 (2010): 58. http://dx.doi.org/10.1071/sr09067.
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Clearing native vegetation and introducing crops and pastures may increase deep drainage and result in dryland salinity. In south-west Queensland, native vegetation of the Goondoola Basin has been substantially cleared for cropping and pastoral activities, resulting in shallow groundwater and localised salinity. Simulation modelling was used to estimate the water balance of a range of vegetation and soil types. Six soils were studied, with plant-available water capacity (PAWC) of 71 mm (a Kandosol) to 198 mm (a Vertosol) for 1200 mm depth. Vegetation types were annual wheat, opportunity cropping, and perennial pastures in poor and good condition, and high quality perennial pasture with deep roots growing on deep (2400 mm) variants of the 6 soil types. Opportunity cropping did not reduce deep drainage. Substantial differences were found in long-term average deep drainage (mm/year) between wheat crops and pastures for all soil types. The differences in deep drainage between wheat cropping and pasture in good condition were greatest for the 2 Kandosols, which had the lowest PAWC (34 and 21 mm/year less deep drainage, reductions of 53% and 62%, respectively), and a Vertosol with intermediate PAWC (23 mm/year less deep drainage). A Chromosol and a Dermosol with intermediate PAWC had smaller reductions in deep drainage (14 and 11 mm/year, respectively). In the case of a Vertosol with high PAWC (198 mm), deep drainage was negligible with all pastures. Due to increased infiltration and reduced soil evaporation, more deep drainage was simulated with pasture in good condition than pastures in poor condition, especially for 2 Kandosols. Pasture with deep roots (2400 mm) growing on deep variants (2400 mm) of the 6 soils had lower rates of deep drainage than the other pastures. Simulated deep drainage and other components of the water balance were in good agreement with field measurements and expectations. These results indicate that large reductions in deep drainage can be achieved in the Goondoola Basin by replacing cropping with pastoral activities. Kandosol soils used for wheat cropping should be the primary target for land use change.
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Chan, K. Y., A. Oates, G. D. Li, M. K. Conyers, R. J. Prangnell, G. Poile, D. L. Liu, and I. M. Barchia. "Soil carbon stocks under different pastures and pasture management in the higher rainfall areas of south-eastern Australia." Soil Research 48, no. 1 (2010): 7. http://dx.doi.org/10.1071/sr09092.
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In Australia, pastures form the basis of the extensive livestock industries and are important components of crop rotation systems. Despite recent interest in the soil carbon sequestration value of pastures in the mitigation of climate change, little information is available on the soil carbon sequestration potential of pastures in New South Wales farming systems. To quantify the soil carbon stocks under different pastures and a range of pasture management practices, a field survey of soil carbon stocks was undertaken in 2007 in central and southern NSW as well as north-eastern Victoria, using a paired-site approach. Five comparisons were included: native v. introduced perennial, perennial v. annual, continuous v. rotational grazing, pasture cropping v. control, and improved v. unimproved pastures. Results indicated a wide range of soil organic carbon (SOC) stocks over 0–0.30 m (22.4–66.3 t C/ha), with little difference when calculated based on either constant soil depth or constant soil mass. Significantly higher SOC stocks were found only as a result of pasture improvement using P application compared with unimproved pastures. In this case, rates of sequestration were estimated to range between 0.26 and 0.72 t C/ha.year, with a mean rate of 0.41 t C/ha.year. Lack of significant differences in SOC stocks for the other pastures and pasture management practice comparisons could be due to inherent problems associated with the paired-site survey approach, i.e. large variability, difficulties in obtaining accurate site history, and the occasional absence of a valid control as well as the likely lower rates of SOC sequestration for these other comparisons. There is a need for scientific long-term trials to quantify the SOC sequestration potential of these other pastures and pasture management practices.
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Eyles, Alieta, Garth Coghlan, Marcus Hardie, Mark Hovenden, and Kerry Bridle. "Soil carbon sequestration in cool-temperate dryland pastures: mechanisms and management options." Soil Research 53, no. 4 (2015): 349. http://dx.doi.org/10.1071/sr14062.
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Permanent pastures, which include sown, native and naturalised pastures, account for 4.3 Mha (56%) of the national land use in Australia. Given their extent, pastures are of great interest with respect to their potential to influence national carbon (C) budgets and CO2 mitigation. Increasing soil organic C (SOC) mitigates greenhouse gases while providing other benefits such as pasture productivity, soil health and ecosystem services. Several management approaches have been recommended to increase C sequestration in pasture-based systems; however, results have proved variable and often contradictory between sites and years. Here, we present an overview of the processes and mechanisms responsible for C sequestration in permanent pastures. In addition, we discuss the merits of traditional and emerging pasture-management practices for increasing SOC in pastures, with a focus on dryland pasture systems of south-eastern Australia. We conclude by summarising the knowledge gaps and research priorities for soil C-sequestration research in dryland pastures. Our review confirms that soils under a range of pasture types have considerable potential for sequestration of atmospheric CO2 in Australia, and that the magnitude of this potential can be greatly modified by pasture-management practices. Although the shortage of long-term studies under Australian conditions limits our ability to predict the potential of various management approaches to sequester soil C, our review indicates that prevention of erosion through maintenance of groundcover and adoption of options that promote deep C sequestration are likely to confer broad-scale maintenance or increases in SOC in pasture soils over a decade or longer. We acknowledge that the evidence is limited; therefore, confidence in the recommended practices in different locations and climates is largely unknown.
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Scott, J. F., G. M. Lodge, and L. H. McCormick. "Economics of increasing the persistence of sown pastures: costs, stocking rate and cash flow." Australian Journal of Experimental Agriculture 40, no. 2 (2000): 313. http://dx.doi.org/10.1071/ea98016.
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Poor persistence of sown pastures, trends of low pasture resowing rates and a substantial decline in carrying capacity of non-crop areas bring into question the basis of the philosophy of pasture improvement by sowing pasture species. If graziers are to adopt grazing strategies or stocking rates that are more ecologically sustainable, then clearly they must also be cost-effective in either increasing income or reducing costs so that they are economically sustainable. This paper describes the use of an interactive spreadsheet model developed to assist graziers and their advisers with assessing the long-term profitability of pasture management and/or improvement (and therefore pasture persistence). The model provides a comparative cash flow for different levels of inputs (fertiliser, herbicides and feed supplements) over a 15-year period. Results clearly show that at the same stocking rate, different animal enterprises have markedly different profitabilities over a 15-year period. Further, for native, improved and sown pastures, the most profitable pastures are those that can sustain increased stocking rates for long periods of time, without the need for resowing.
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Jones, C. E. "Pastoral value and production from native pastures." New Zealand Journal of Agricultural Research 39, no. 4 (December 1996): 449–56. http://dx.doi.org/10.1080/00288233.1996.9513206.
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Johnston, W. H., P. S. Cornish, and V. F. Shoemark. "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, no. 4 (2005): 401. http://dx.doi.org/10.1071/ea03117.
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A grazing experiment conducted in Wagga Wagga (New South Wales) from September 1993 to September 1998 compared the productivity of pastures containing 3 palatable types of summer-active Eragrostis curvula complex, with pastures containing either Medicago sativa or Phalaris aquatica. Issues relating to the management of E. curvula pastures were also investigated. Herbage growth rates of the P. aquatica and M. sativa pastures were highest in winter and spring; E. curvula pastures were most productive in summer and autumn. Stocking rates equivalent to 30–40 dry sheep were carried by the pastures during their growing seasons. Throughout the study, the pastures were dominated by their respective sown perennial species, however, a suite of desirable and undesirable annual grasses and annual legumes usually contributed >20% of total herbage mass in spring. The P. aquatica pasture contained a higher proportion of weedy species than the other pastures, especially C4 grasses and broadleafed species, and towards the end of the experiment it was also invaded by several native perennial grasses. Overall, the wool yield from the M. sativa pasture was 0.5–1.0 kg/animal.year higher than the other pastures. Management to minimise herbage accumulation on the E. curvula pastures was a key issue, and provided that pastures were grazed heavily, this was achieved by the rotational grazing strategy used in the experiment. It was concluded that palatable varieties of E. curvula have a useful and complementary role as perennial pastures in southern Australia. By increasing herbage availability in summer and autumn, E. curvula may improve management flexibility for a wide range of pastures that are commonly grown on farms.
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Badgery, W. B., D. R. Kemp, D. L. Michalk, and W. McG King. "Studies of competition between Nassella trichotoma (Nees) Hack. ex Arechav. (serrated tussock) and native pastures. 1. Adult plants." Australian Journal of Agricultural Research 59, no. 3 (2008): 226. http://dx.doi.org/10.1071/ar07112.
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Nassella trichotoma (serrated tussock) is a hardy perennial grass weed that rapidly invades disturbed areas. Pasture competition is an important component of an integrated weed-management system for native pastures. This paper reports on a field experiment to ascertain the level of competition from native grasses for adult N. trichotoma plants. Native grasses prevented N. trichotoma plants from increasing in biomass and basal area when rotationally grazed or when grazing was removed and fertiliser was withheld. Smaller N. trichotoma plants (<500 mm2) were more likely to vary in size with very little change in larger plants. Flupropanate efficiently killed all N. trichotoma plants but caused considerable damage to perennial native species, resulting in an uncompetitive pasture dominated by broadleaf weeds.
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Papadopoulos, Y. A., H. T. Kunelius, and A. H. Fredeen. "Factors influencing pasture productivity in Atlantic Canada." Canadian Journal of Animal Science 73, no. 4 (December 1, 1993): 699–713. http://dx.doi.org/10.4141/cjas93-076.
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Most pastures in Atlantic Canada are classified as permanent and contain primarily native species. Well-managed native swards have the potential of supporting profitable animal output. Productive cultivars of cool-season perennial grass species such as timothy (Phleum pratense L.), orchardgrass (Dactylis glomerata L.), tall fescue (Festuca arundinacea Schreb.), reed canarygrass (Phalaris arundinacea L.) and legumes such as white clover can increase pasture productivity in the region and ameliorate seasonal fluctuations in dry matter yield associated with native swards. Improved swards gradually revert to native species, partly because forage cultivars and mixtures are not assessed for persistence under grazing.Soil acidity and deficiencies in soil nutrients were shown to reduce herbage yield, legume content of the grazed swards and mineral content of the herbage, all of which may adversely affect livestock performance. High concentrations of K, observed in swards heavily fertilized with N, are likely to cause problems in the metabolism of Ca and Mg in lactating ruminant livestock grazing such swards.Supplemental pasture crops, including annual ryegrass (Lolium multiflorum Lam.) and Brassica species, extend the productive grazing season from approximately 4 to 7 mo, and permit the production of large quantities of biomass close to the barn.Rotational grazing and forward creep-grazing techniques at high stocking rates can improve the number of animal grazing days and average daily gains. Previous experience with grazing and exposure to pasture species before and during weaning appear to influence grazing behavior and species preference of newly weaned livestock. The use of previous grazing experience may help create the desired pasture sward or improve the efficiency of sward utilization by the grazing animal. The high rainfall climate of the Atlantic region, which promotes good herbage production, also encourages heavy and prolonged infestations of infective free-living stages of gastrointestinal parasites on pastures. Permanent pasture is the main source of initial herd infection, which then spreads to newly seeded pastures. Strategic treatments of grazing livestock with anthelmintic drugs are recommended to minimize the impact of these parasites on the productivity of grazing livestock in this region. Key words: Pasture, Atlantic Canada, productivity, grazing management, fertility management, Brassica spp., grasses, legumes
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McIvor, JG, and CJ Gardener. "Pasture management in semi-arid tropical woodlands: effects on herbage yields and botanical composition." Australian Journal of Experimental Agriculture 35, no. 6 (1995): 705. http://dx.doi.org/10.1071/ea9950705.
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The effects of pasture management options (introduced legumes and grasses, superphosphate, timber treatment, cultivation before sowing, stocking rate) on the yield and botanical composition of pastures were measured from 1982 to 1992 at 2 sites, Hillgrove (extractable phosphorus, 50 mg P/kg) and Cardigan (extractable P, 6 mg/kg), near Charters Towers, northeastern Queensland. Despite generally poor establishment and growing conditions, some sown species (Stylosanthes hamata, S. scabra, Cenchrus ciliaris, Urochloa mosambicensis) established and persisted at both sites. The initial sown grass populations were small but yields increased markedly towards the end of the experiment. There were no yield responses by the native pastures to superphosphate, but the sown pastures responded at Cardigan, although not at Hillgrove. There were large yield responses to tree killing. The percentage increase in herbage yield following tree killing increased as the available water in the soil during the growing season decreased, and was greater at the higher fertility Hillgrove site. Overall, the native pastures were dominated by perennial grasses, but annual grasses and forbs increased on plots with live trees and high stocking rates towards the end of the trial. sown grasses, particularly C. ciliaris, became dominant (and are likely to remain so) at Hillgrove and on plots with superphosphate at Cardigan, especially where the trees were killed. Productive, mixed pastures with reasonable proportions of both grass and legume were maintained under live trees.
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Floate, K. D., and N. Kadiri. "Dung beetles (Coleoptera: Scarabaeidae) associated with cattle dung on native grasslands of southern Alberta, Canada." Canadian Entomologist 145, no. 6 (September 10, 2013): 647–54. http://dx.doi.org/10.4039/tce.2013.50.
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AbstractSurveys of dung beetles establish the dominance of exotic taxa associated with cattle dung on native grasslands in southern Alberta, Canada. Of the 12 species recovered, eight were of European origin and comprised 92.2% of the total catch of 187 963 beetles. Most common wereChilothorax distinctus(Müller),Onthophagus nuchicornis(Linnaeus), andColobopterus erraticus(Linnaeus) (Coleoptera: Scarabaeidae). The abundance ofC. distinctushas been known in the region since the 1920s, whereas that ofO. nuchicornisonly was first reported in the 1990s. The abundance ofC. erraticushas not previously been observed in the region and identifies the species as the newest addition to the endemic fauna. The diversity of native species on pastures in southern Canada and adjacent states is depauperate, such that the establishment of European taxa has appreciably increased levels of bioturbation in pasture ecosystems. The success of these exotic species on northern pastures may reflect a level of cold-tolerance greater than that of most native species.