The East Otago region has been at the forefront of agricultural advancement in New Zealand with key people leading the way in creating a culture of innovation. Rural technology developments are traced back from the emerging new biotechnology industries, through animal genetics research, improvements in hill country and pasture production, soil and fertiliser research, the introduction of deer farming and sheep breeding, to the frozen meat shipments, agricultural organisation restructuring and land reforms of the early settlers. Keywords: deer, genetics, grazing management, history, innovation, sheep, soil classification, soil fertility, technology
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(81 KB)Forage seed (brassica, grass and legume species) is the delivery vehicle for new plant genetics to the pastoral sector. Seed production technology associated with the release of the first bred pasture cultivars in the 1930s was largely based around horse-drawn reaper and binders and stationary threshing machines. The development of authenticity and quality controls also started in the 1930s with the NZ Seed Certification Scheme. Management inputs were minimal with closing and harvest dates being the major tools available. Over a 75 year period, seed yields have increased, with top growers now achieving seed yields that are three times greater than those reported 50 to 75 years ago. In the 1950s, harvest mechanisation developed rapidly and in the 1970s on-farm seed drying was developed. The availability of nitrogen (N) fertiliser was the first major input available for grass seed growers. The paper follows the science and changing recommendations on N rates and the eventual maximum limit achieved by additional N identified in trials in 2004. From the 1960s onwards, new herbicides have allowed for the control of a wider range of difficult to control weed species, especially the control of other grasses in ryegrass seed crops and broadleaved weeds in white clover. New generation fungicides, insecticides and plant growth regulators have provided improved management tools for increased seed yields. The paper concludes with changes in extension from Government driven (Department of Agriculture) to farmer funded R&D and extension by the Foundation for Arable Research. Keywords: ryegrass, white clover, brassica, seed production, history
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(90 KB)We reflect on what has been a recurring theme in the history of agricultural research in NZ – the understanding that while we grow white clover for its capacity to fix nitrogen, this increase in fertility ultimately passes to benefit the accompanying grass. The association of clover and grass is regarded both as a wonderful harmony upon which our economy depends, but also as a competition between species that too often defeats our efforts to realise clover’s full potential. We review and revisit the nature of the interaction between the species, and we offer some radical approaches looking forward. These include simple pragmatic options for management for immediate gains in performance, and we identify the need for some critical rethinking to fundamentally alter how grass and clover interact. Keywords: grass, clover, cycles, patch dynamics, competition
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(187 KB)I would firstly like to acknowledge the many members, presenters, organisers and executive members who have given there time and valuable input over the last 75 years making the NZ Grasslands Association the organisation it is today. The 68 proceedings are an invaluable record of NZ’s post 1920s pastoral history and developments. It provides a scientific record with all its insights but also a time capsule of issues of the day and farm practices.
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(130 KB)
Scientific and technological advances are important for any industry to ensure continued improvement in productivity – achieving more output of value per unit of input. Since the majority of New Zealand’s pastoral produce is traded internationally we need to ensure that we are the most efficient at growing and producing this produce, whether it is traded as a commodity or as a value added product. The requirement for continued R & D investment in our agricultural knowledge economy is a prerequisite for continued improvements in pastoral agricultural productivity. In reflection, the major scientific and technological advances that have improved on-farm productivity over the last 75 years are described and the challenge is given to determine how this might continue into the future. Keywords: pastoral agriculture, research and development, technologies
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(272 KB)Over the past 5 years a herd of up to 180 cows has been milked by two automated milking systems (AMS) at the Greenfield Project research farm near Hamilton. The performance parameters pertaining to pasture management and pasture utilisation during the 2004/05 season are described. The 54 ha farm had an estimated net pasture accumulation of 16.2 t DM/ha/yr. The estimated pasture consumption was determined using back calculations to be 12.3 t DM/ha/yr resulting in an estimated efficiency of pasture utilisation of 76% (based on consumed vs. net accumulation). The data presented suggest that it is possible to achieve satisfactory pasture intakes, pasture utilisation and to be able to maintain pasture quality with automatic milking in a low-input, pasture-based system. Keywords: automatic milking, grazing, pasture management, pasture utilisation
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(123 KB)A long-term field study is being conducted in New South Wales, Australia, to evaluate the feasibility of producing over 40 t DM/ha/year with a triple crop, complementary forage rotation (CFR) system. The CFR comprises a bulk crop (maize); a break crop (forage rape) and a legume crop capable of fixing atmospheric nitrogen (clover). The control is a well managed kikuyu-based pasture oversown with short rotation ryegrass each autumn. Treatments are replicated four times and data from the first 2 years are reported. Over 40 t DM/ha/year was either utilised by grazing or harvested mechanically from the CFR system in the first 2 years. This compares to almost 18 t DM/ha/year of utilised pasture for the control pasture system. In practice, these results indicate that dairy farmers in Australia can increase productivity by growing more forage on-farm with increased efficiency. The systems are designed to complement, rather than substitute, pasture-based systems. Keywords: complementary forage rotation, pasture, crop, dairy
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(81 KB)Increasing the current precision of nutrient management will need analytical tools that aid in collecting site specific data. A technology with potential is hyperspectral remote sensing. Modern, portable spectroradiometers permit reflectance data in the spectral region between 350 and 2500 nm to be collected quickly. With the limited sampling, handling, and processing required the technology also offers rapid turn around times, if calibrations can be developed. In this paper the findings of a pilot study examining the use of hyperspectral reflectance spectra of pasture to indirectly assess the phosphorus (P) status of the soil are presented and discussed. Spectral data were collected in spring 2004 and again in summer 2006 from a small area of each of 30 legume-based sheep grazed pasture plots that varied in soil P fertility (Olsen P 6-68 μg/ml). Significant (P<0.05) relationships were found with two commonly used vegetation indices and pasture P content (R2 >0.80). In an exploratory analysis using all the spectral waveband data, several paired-bands with high coefficients of determination (R2) were detected for pasture P and K content, but not for pasture N content, pasture growth rate or pasture dry matter content. The differences detected in pasture P content were consistent with the differences in soil P fertility measured by the Olsen P soil test, as indicated by the relationship between pasture P content and soil Olsen P in both 2004 (R2 = 0.90) and 2006 (R2 = 0.86). This pilot study needs to be broadened to examine other methodologies for interpreting the spectral data and extended to other pasture types and soil groups of varying soil fertility. Keywords: Olsen P, soil fertility, remote sensing, hyperspectral imaging, spatial variability, soil phosphate, plant phosphate
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(238 KB)
The effects of temperature, water and nitrogen on pasture production of an 8 year old ‘Wana’ cocksfoot pasture were quantified at Lincoln University, Canterbury. The maximum dry matter (DM) yield was 22.0 t/ha/yr when neither water nor N were limiting. Crude protein yield of +N pastures was 3.2-4.2 t/ha/yr compared with 1.0 t/ha in –N pastures. Metabolisable energy averaged 178*103 MJ ME/ha/yr for the +N pastures compared with 69*103 MJ ME/ha/yr for –N pastures. Seasonal differences in pasture production were explained in relation to thermal time with 7.0 kg DM/oCd for N fertilised pastures and 3.3 kg DM/oCd when no N was applied. During periods of water stress, relative yield decreased at a rate of 1.4%/mm when the soils critical limiting deficit of 78 mm was exceeded. Keywords: Dactylis glomerata, irrigation, nitrogen, thermal time.
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(131 KB)Liveweight gain of ewes and lambs and subterranean clover reproduction were measured in tall fescuesubterranean clover pastures on a dry, stony soil stocked at 10 (low) and 20 (high) ewes and their twin lambs/ha over 46 days in spring 2005. Lambs grew at 374 g/day at the low stocking rate and 307 g/day at the high stocking rate, meaning final liveweight was 3.1 kg higher at the low stocking rate. However, lamb liveweight gain/ha/ day was greater at the high (12.3 kg/ha/day) than the low (7.5 kg/ha/day) stocking rate. Ewes gained 2.2 kg at the low stocking rate and lost 4.9 kg at the high stocking rate, with most liveweight loss occurring in the second half of the grazing period when moisture stress restricted subterranean clover growth. There were 62% fewer burrs/ m2 at the high than the low stocking rate. For both stocking rates, inadequate seed production resulted in inadequate seedling numbers in the following autumn (285 and 223 seedlings/m2 at low and high stocking rate, respectively). The results show high lamb liveweight gains can be obtained on subterranean clover pastures, but, in a drier than average spring, selective grazing of the clover may result in poor subterranean clover seed production and reduced seedling numbers in the following the autumn. Keywords: liveweight gain, seed production, sheep grazing, stocking rate, subterranean clover, tall fescue
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(116 KB)In 1977, we purchased a 1983 ha property carrying 1.5 SU/ha (3000 SU) to develop it to carry 5 SU/ha (10,000 SU) finishing all stock. The property runs from 170 to 1000 m a.s.l. To achieve this large increase in stocking rate we: • Used a combination of oversowing and cultivation to successfully establish pasture • Topdressed with adequate rates of superphosphate and lime • Changed to a more productive sheep breed • Introduced a two tier cattle system to gain the advantages of cross-breeding
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(52 KB)The temporal (seasonal) pattern of dryland pasture and stock production from four cocksfoot based pastures (mixed with balansa, Caucasian, subterranean or white clover), a ryegrass/white clover pasture and a pure lucerne crop were compared over 2 years (2004/05 and 2005/ 06). Subterranean clover with cocksfoot provided high legume content pasture giving higher stock production than other pasture mixtures from August to October. This complemented the high yields and stock production provided by lucerne from mid September to January in 2004/05. However, a dry winter followed by spring snow resulted in lucerne production similar to other pastures in 2005/06. Cocksfoot based pastures provided more maintenance feed than perennial ryegrass during a dry summer (2005/06) but ryegrass/white clover provided higher stock production in wet summer conditions (2004/ 05). These results suggest a range of pasture species are necessary to cope with the seasonal climate variability typically experienced in dryland farm systems. Keywords: balansa clover, Caucasian clover, Dactylis glomerata, Lolium perenne, Medicago sativa, pasture growth rates, ryegrass, sheep production, Trifolium ambiguum, Trifolium michelianum, Trifolium repens, Trifolium subterraneum, white clover
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(309 KB)A trial was laid down at Woodlands in Southland to investigate the effect of pasture manganese (Mn) on sheep performance. Pasture Mn concentrations were increased from background concentrations (82-98 mg/kg DM) to 192-354, 466-694 and 912-1178 mg/kg DM by the regular spray application of MnSO4. These pasture concentrations were replicated four times and grazed by mobs of 10 Coopworth x Texel ram lambs. Pasture growth, botanical composition and pasture Mn concentrations were monitored. Lamb liveweights were measured fortnightly and the lambs were slaughtered after 14 weeks with the livers of six animals from each treatment sampled for vitamin B12, copper (Cu), selenium (Se) and Mn concentration. Average clover content of the pastures declined throughout the trial, averaging 17%, 15% and 4% for the three grazing areas respectively. Animal growth rates averaged 180 g/day for the duration of the experiment but varied from 250 g/day during the first 2 weeks they grazed the pastures declining steadily for each 2 week period they remained on that group of paddocks to a low of <90 g/day after 6 weeks. The animal growth rates were only significantly influenced by extremely high initial Mn concentrations (>2000 mg/ kg DM) or where concentrations were above 1200 mg/ kg DM for the full 2 week grazing period. There was no effect of high Mn intake on liver B12, Se, Cu or Mn under these conditions. Keywords: sheep, manganese, lamb growth rates, pasture manganese concentration
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(117 KB)Browse blocks were developed on wet rush-infested areas of Riverside Farm, near Masterton, by planting 6,000 willow stakes/ha over the winter periods of 2000, 2001 and 2002. This was followed by light grazing in the first year after planting and then more intensive grazing in later years. After 18 months the areas dried out, due to evapotranspiration from the trees, and a herbage sward developed from volunteer species. The quality of the herbage progressively improved over a 4 year period and the browse blocks now support year-round grazing by sheep. In Experiment 1, ewes that grazed willow browse blocks for 86 days in 2004 (including mating) had higher reproductive performance than ewes that were mated on short, drought affected pasture. However, reproductive performance was lower than that from ewes mated on a sole diet of long herbage similar to that growing in the browse blocks. It was calculated that 15 and 65% of the metabolisable energy and condensed tannins consumed by ewes grazing browse blocks was provided by willow trees. In Experiment 2, undrenched lambs grazing either control pasture or browse blocks for 98 days in 2005 had lower liveweight and carcass gains than lambs regularly drenched with anthelmintic. Lambs grazing browse blocks consistently had lower dag scores and undrenched lambs grazing on browse blocks had reduced worm burdens of some economically important internal parasites compared with undrenched lambs grazing pasture. It was concluded that the benefits of browse blocks could be due to both direct and indirect effects and that any benefits in internal parasite management may be accompanied by reduced rates of carcass growth. Guidelines are presented for the grazing management of willow browse blocks over a complete 12 month period. Keywords: willow (Salix), fodder tree, drought, internal parasites.
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(100 KB)
Organic farming in New Zealand is not considered a mainstream option for farmers. This paper compares organic and conventional farms running side by side at Avalon Farming and details why Avalon Farming is expanding its organic area. Included in the paper are details of the conversion to organic farming and its success. Topics include: 1. Challenges of converting from a conventional to an organic system. 2. Comparing conventional and organic production and the financial returns. 3. Marketing options for organic farmers in New Zealand including the growth of farmers markets.
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(81 KB)The need for anthelmintic drenching varies from animal to animal. To avoid unnecessary use of drenches it is therefore desirable to formulate drenching rules that apply to the individual, rather than the mob. We used a computer decision support tool called the general planner for agro-ecosystem models (GPAM) to investigate drenching rules for lamb production on a dual organic-conventional farm. The GPAM was combined with a dynamic model of nematode infection in lambs to help understand how varying premiums for organically produced lamb affected optimal drenching decisions. Simulations showed that there was no incentive to produce lambs organically if the premium for organic meat was less than 20%. Even when the premium was increased to 80%, half the lambs slaughtered had conventional status. As the premium increased, more lambs were produced organically and there was greater variation in liveweight between animals, whether drenched or undrenched. This modelling exercise demonstrated that there is potential to devise individualised drenching strategies that return the greatest carcass value for the entire mob. However, it is also clear that without alternative non-anthelmintic strategies to control infection, a significant proportion of the flock will have to be finished using drenches even with high premiums for organic lamb. Keywords: organic lamb production, nematode infection, decision making, artificial intelligence
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(257 KB)Gastrointestinal parasitism is one of the most important challenges facing low chemical or organic livestock production systems but also conventional farmers as resistance to anthelmintics becomes more widespread. Young twin-born and reared lambs were challenged for 5 days (Experiment 1) or trickle infected with parasites (Experiment 2) and not weaned (Expt. 1. only) or early (8 and 7 weeks) or late weaned (16 and 14 weeks; Expt. 1 & 2 respectively). Liveweight gain was measured until lambs were 19 weeks of age (Expt. 1) or 25 weeks of age (Expt. 2). Early weaning (7-8 weeks) reduced liveweight gain by at least 25% in both years and lambs remained 5 kg lighter at the completion of the experiments. Parasite infection had modest effects on lamb performance and there was no interaction between weaning age and parasite infection in either year. Infected lambs generally grew well, gaining at least 90 g/d possibly due to the relatively young age of the lambs limiting their ability to mount an immune response. Keywords: gastrointestinal parasites, low chemical, organic livestock production, sheep, growth rates
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(85 KB)A long-term replicated farm systems study (1997-2005) examined changes in the biology of mixed-livestock systems associated with the shift to organic production. Two farmlets were managed using conventional farm practices (Con) and two low chemical (LC) farmlets complied with the organic production standards of BIOGRO New Zealand. The Con farmlet had higher (P<0.01) lamb, hogget, 2TH and mixed-aged ewe (P<0.01) performance than the LC farmlet due mainly to differences in the parasite challenge between the two systems. There was no evidence that the use of the Ivermectin® bolus for 8 consecutive years in the Con system led to Ivermectin® drench resistance. Lamb liveweight at weaning was 1.77 kg lower (P<0.001), in LC than in Con. Post-weaning, high parasite burdens (FEC) reduced (P<0.001) LC lamb growth rate. LC systems had smaller 2TH’s (P<0.001) and mixed aged ewes (P<0.001) than Con systems, despite similar feeding levels, leading to lower ovulation rate and numbers of lambs born. Lamb mortality rates between lambing and weaning were similar between systems. Until production losses in young stock following weaning in LC systems are reduced, the ability of the organic industry to expand will continue to be constrained. Performance differences between systems did not change over the 9-year trial, suggesting that this study provides a good insight into the relative performance of these two systems at the stocking rate at which they were compared. Pasture composition and production, and soil biophysical and biological characteristics were similar in the two farm systems. Keywords: low chemical, organic, farm systems Ivermectin
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(89 KB)A dynamic model for nematode parasites in lambs which links their adult worm burden with decrease in liveweight gain has recently been developed. This model allows for individual lamb variability in response to parasite infection. We use this model to track the liveweight performance of a mob of weaned lambs under six different grazing rotation length scenarios. In all scenarios, lambs with a low worm burden were weaned onto parasite-free pasture. Post-weaning, lambs were either grazed in a 12-week, 8-week, 6-week, 4-week or 2-week grazing rotation, or set stocked. Scenarios were run for 24 weeks with no anthelmintic intervention. The 12-week and 8-week grazing rotation scenarios provided lower worm burdens, higher liveweight gains and lower variation between individual lambs than the other scenarios due to the delay in grazing self-contaminated pastures. For systems that use little or no anthelmintics, being able to provide 8 weeks or more of parasite-free pasture to weaned lambs is likely to provide substantial benefits in the form of higher liveweight gains with less variation between individuals. Keywords: grazing, lambs, liveweight, modelling, parasites
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(248 KB)
Researchers in the AgResearch deer programme are using social research to understand the level of environmental awareness amongst farmers. Our aim in this research was to understand the issues surrounding waterway fencing amongst farmers in Otago and Southland. Both quantitative and qualitative data were collected as part of this project. Our findings indicate that the level of environmental awareness amongst farmers was influenced by their specific farm context. Many farmers were defensive when explaining their reasons for or against waterway fencing. Those farmers who did fence off waterways did so for practical reasons. Many believed it was impossible to fence off their waterways. Our findings suggest that the imperatives for fencing have to be balanced with the practicalities. These practicalities tended to centre on the number of streams that would be required to be fenced and the nature of the stream. Many farmers believed they were doing the ‘best they could’ and therefore did not feel they needed to adopt new environmental practices. Keywords: environmental awareness, waterway fencing, deer farming
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(115 KB)Water Use Efficiency (WUE) is an important performance indicator of sustainable production, widely used overseas. WUE is defined in a number of ways, and it is important to know what definition is being used. Overseas data show that WUE on dairy farms depends on both the efficiency of applying water to the paddock, and the efficiency of feed utilisation off the paddock. Pasture WUE requires measurements of the amount of water applied and the amount of pasture produced, which are rarely concurrently measured on dairy farms. Estimates of pasture WUE from previous research experiments are highly variable because of uncertainties about how much water was applied. We have suggested a benchmark for WUE based on measurements on commercial dairy farms, and suggest some ways that farmers can improve their irrigation practices. Keywords: water use efficiency, pasture yield, irrigation, evapotranspiration
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(104 KB)Two experiments determined the potential of N fertiliser to maximise the conversion of summer (October to April) irrigation water to pasture dry matter (DM) in southwest Victoria, Australia. DM consumed increased with increasing N (0 to 100 kg N/ha per grazing, and 50 to 200 kg N/ha every second grazing). Applications of 75 to 100 kg N/ha every grazing, and 150 to 200 kg N/ha every second grazing resulted in the highest water use efficiencies (improvements of 25 to 70% in Year 1, 40 to 63% in Year 2). Applications of 25 kg N/ha every grazing and 50 kg N/ha every second grazing led to the highest N response efficiencies (10 to 19 kg DM/kg N). The increases in DM consumed in response to N fertiliser were similar to responses noted for N applied during autumn, winter and spring in similar environments to the current experiments. Keywords: dry matter, perennial ryegrass, urea, water use efficiency
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(76 KB)Research on the soil and water quality of deer farms is minimal. However, the perception is that many deer operations may be detrimental to soil and water quality. To address this problem two deer focus farms (DFF, 1 each in Otago and Southland) were established to showcase how productivity and environmental objectives can coincide. Managements implemented by the farmers included a sedimentation pond, fencing off waterways and retiring land under a QEII covenant. A detailed soil and water quality testing regime occurred for each farm: data were collected at the Southland DFF for three tributaries (one fenced off, one partially fenced and one unfenced) which fed into a stream and through a tussock covered area retired from grazing. Water quality in the unfenced and partially fenced tributaries was poor with no water quality parameters meeting ANZECC guidelines, whereas water quality in the fenced-off and planted tributary was better. Water exiting the retired area met ANZECC guidelines. Although water quality on parts of both deer farms did not meet ANZECC guidelines, when management practices such as fencing off and the creation of a pond were used water quality improved. More importantly, an area retired from grazing and further development on the Southland DFF showed that water quality could be significantly improved and could be better than that entering the farm. Keywords: fencing-off, QEII covenant, sedimentation pond, water quality
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(216 KB)Applying water efficiently is increasingly important for dairy farmers and other users of surface and groundwater resources to maintain sustainable production. However, irrigation is rarely monitored. We used a questionnaire survey and measurements of five spray irrigation systems working in normal farm conditions to make observations on how efficiently irrigation is being managed. Survey results from 93 dairy farmers showed that, although the farmers believe they know how much water is being applied during irrigation, only 60% make measurements, and about 18% measure irrigation uniformity. Catch-can measurement of irrigation application depth for the different spray systems indicated large variability in application depths during irrigation, and field distribution uniformity ranged greatly between the different systems, decreasing in the order of centre pivots >travelling irrigators> K-line. Changes in irrigation system settings were sometimes made without considering application depths or uniformity. If our five case studies are typical, they may explain the large range of seasonal irrigation amounts recorded in the survey. We recommend that farmers monitor irrigation application depths and uniformity to help manage irrigation water efficiently and to help them estimate the value of irrigation to their enterprise. Keywords: distribution uniformity, water use efficiency, catch cans
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(152 KB)The New Zealand agricultural industry is currently undergoing a large drive for increased productivity. Fuelling this will primarily require greater ‘on-farm’ landuse intensification involving increasing farm inputs to gain a large increase in farm product outputs. The North Otago Rolling Downlands (NORD) region of New Zealand has traditionally been drought-prone and limited to extensive sheep farming. The establishment of a large district irrigation scheme in spring 2006 will result in large scale intensification of land-use across the NORD region. A field trial has been established in North Otago on a common NORD Pallic soil type (Timaru silt loam) to determine the effect of land use intensification on soil quality and plant yield response. The treatments compare newly sown pasture vs. winter grazed forage crop, irrigated vs. dryland and sheep vs. cattle grazing. The application of irrigation water in 2004/2005 resulted in 17.5 kg pasture DM/mm of irrigation water and 24 kg pasture DM/mm of irrigation water for the drier 2005/ 2006 growing season. Results from the pasture trial suggest that both cattle grazing and irrigation (particularly in combination) are decreasing soil quality with a macroporosity of 9% v/v from pasture plots following the 2004/2005 season compared to 18% v/v for the dryland sheep treatment. In the 2005/2006 season, cattle irrigated plots had a macroporosity of 11% v/v from pasture plots c.f 19% v/v for the dryland sheep treatment To date, this measured decrease has had no significant effect on pasture or crop yield suggesting that soil quality has not yet fallen below a critical level for production under irrigated farming systems. However, further monitoring is required to assess the long term effects as strong trends are emerging that indicate soil quality decline under the cattle grazed and cropping treatments. Keywords: land-use intensification, soil quality, irrigation, cattle grazing, sheep grazing, forage cropping, compaction, pasture yield
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(116 KB)The irrigation of perennial pasture and the growing of dryland summer forage crops are two common methods of increasing the supply of and nutritional value of home grown forage on dairy farms in south west Victoria. In recent years the amount and reliability of supply of irrigation water to dairy farmers in the region has decreased through drought and increased regulation. Over the last 8 years a series of studies have been conducted to investigate the most efficient use of unreliable irrigation water supplies. Perennial pasture was found to be particularly sensitive in terms of reduced productivity and water use efficiency (WUE) to poor irrigation practices. However, under good management and reliable water supply it is still likely to be the easiest and most economically efficient irrigation system. Irrigated summer forage crops were found to have a higher WUE, but responses were variable due to year to year seasonal differences. These crops were found to be more tolerant of poor irrigation management and were able to take advantage of reduced amounts of irrigation water and one off irrigations. Keywords: brassicas, forage crops, irrigated pasture, irrigation, water use efficiency.
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(82 KB)
A sample of growers and users of cereal silage in the South Island of New Zealand were surveyed in 2005 to quantify results and perceptions. Most users perceived they had positive animal responses with 92% reporting that stock performance improved when cereal silage was used as a supplement to grazed pasture. Feedback from growers indicated that cereal silage had potential as a high yielding crop but growers estimates of crop yield varied widely. The majority of growers and users were getting results that met or exceeded their expectations. Keywords: cereal silage, whole-crop, green-chop, survey, yields, quality, South Island, performance
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(88 KB)Fertiliser management is an important aspect of growing good forage brassica crops. Every crop has a different requirement, depending on soil fertility and the expected yield response. Systems were developed for forecasting how much fertiliser, and what types, to apply to individual kale and Pasja crops. First, yield responses to fertiliser application were measured in trials in diverse climates and soil fertility conditions. Yield responded strongly to N and P availability, there were few responses to K fertiliser application, and there were no responses to S application. Second, overall responses to the nutrient supply from soil and fertiliser sources were determined in a comprehensive across-trials analysis using the PARJIB model. R-squared values for correlations between actual yields and yields simulated with the PARJIB calibrations were 0.65 and 0.64 for Pasja and kale respectively. Finally, the results were programmed into new software systems (The Kale Calculator and The Pasja Calculator) that deliver a forecast for each crop of the types and amounts of fertiliser that will give the best economic return on the investment in fertiliser. Keywords: The Kale Calculator, The Pasja Calculator, fertiliser application, yield response, PARJIB analysis
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(237 KB)Trade-offs in dry matter (DM) and metabolisable energy (ME) between combinations of three maize silage hybrids varying in maturity from 100-113 CRM and six winter forage options were investigated in a Waikato farmer’s field over 2 years. Winter crops were triticale, cut once; oats grazed 1-2 times; and Tama and Feast II Italian ryegrass, each cut or grazed 2-3 times. Greatest DM and ME production (38.9 t/ha; 396 GJ/ha) was from a 113 CRM hybrid followed by a single-cut triticale crop. The most economical sources of DM and ME were obtained from a 100 CRM maize hybrid plus grazed oats (11.8 c/ kg; 1.12 c/MJ), while the cheapest ME source among cut winter forages was a 113 CRM maize hybrid + triticale (1.18 c/MJ). Reliable annual silage production of 30 t DM/ha and 330 GJ ME/ha (or 3000 kg MS/ha) is possible using a late maturing maize hybrid combined with a winter forage crop such as triticale, although the low feed value of the triticale may limit its use as feed for milking cows. Keywords: Italian ryegrass, oats, maize silage, supplements, triticale, winter forage crops
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(83 KB)Unreliable establishment of brassica forage crops prompted an investigation into the effect of sowing depth and current commercial seed treatments on rates of emergence and total emerged seedling numbers. Three trials using Barkant forage turnip were sown by notillage in conditions managed to minimise invertebrate pressure. Rate of emergence was measured by seedling counts taken at multiple stages over the first 24 days after sowing. Trial A tested the effect of seed treatment (SuperStrike®, UltraStrike™, Gaucho® 600 FS 24 ml/ kg (14.4 g a.i imidacloprid/kg seed), Gaucho® 600FS 12 ml/kg (7.2 g a.i imidacloprid/kg seed) and untreated control) on seed sown at 10 mm depth, with no significant difference in the rate of emergence of any seed treatment and the untreated control (bare seed). Trial B tested the effect of seed treatment (SuperStrike® and untreated control) on seed sown on the soil surface (0 mm), with no difference in rate of emergence being found. Trial C tested the effect of sowing depth (surface (0 mm), 10, 25, 50 mm) on rate of emergence, and found that seed sown at 10 mm depth was initially faster to emerge (7 days after sowing). Subsequent counts established that 10 and 25 mm depths had equivalent rates of emergence and had reached the highest total number of seedlings emerged by 15 days after sowing. In contrast, seed sown on the surface (0 mm) or at 50 mm depth had a lower total emergence count. Trial C also found that subsurface sown seed (10, 25 and 50 mm depths) reached peak number of emerged seedlings faster (15 days after sowing) than seed sown on the soil surface (0 mm). Keywords: brassica, forage crop, seed treatment, sowing depth, emergence, agronomy
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(84 KB)In breeding hind systems, summer is often a period when feed quality and quantity may compromise lactation in the hind and growth of the calf. The growth and feed intake of calves and hinds offered the leaf turnip Pasja were compared to those on a perennial pasture. Calves consumed 1.0 kg forage DM/head/d on pasture and 0.77 kg DM/d on Pasja. The higher digestibility of Pasja meant that the metabolisable energy intake of Pasja was only 1.7 MJ ME/head/d lower than pasture. Hinds grazing pasture consumed 4.8 kg DM/head/d compared with 3.7 kg DM/head/d when fed Pasja. The digestibility of the two diets was not significantly different resulting in an energy intake that was 13.2 MJ ME/d or 33% higher in pasture fed hinds. The weaning weight of calves was 58.3 and 55.2 kg on pasture and the Pasja crop respectively having gained 19.1 and 16.9 kg respectively. Using brassicas to shift feed of high quality from late spring into summer will be best suited to dry environments where the quantity and quality of pasture may not be able to meet the requirements of the lactating hind and her calf. Keywords: calf, digestibility, hind, intake, liveweight gain, stocking rate
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(84 KB)This paper summarises three studies that: 1) compared the feeding value of perennial ryegrass-based pasture with chicory and plantain during 8 weeks grazing by weaner red deer in spring 2003 and 13 weeks grazing plantain by weaner deer during autumn 2004; 2), compared the liver copper, liver and serum vitamin B12 and blood selenium status of weaner red deer grazing ryegrass-based pasture, chicory or plantain for 8 weeks during spring 2003; and 3) determined the effect of grazing perennial ryegrass-based pasture alone, or with intermittent grazing of plantain from 1 month pre-partum to 1 month post-partum on liver copper and vitamin B12 status of calves during December 2004 and January 2005. Feeding value (as determined by liveweight gain) of chicory was 40-48% higher than other forages in spring. Feeding value of plantain was 14% higher than pasture in autumn, but similar to pasture in spring. Grazing chicory significantly enhanced the liver copper concentration of weaner deer in spring compared with both ryegrass and plantain. Grazing plantain significantly enhanced the copper status of weaners in autumn, but not of weaners or calves in spring and early summer, enhanced the vitamin B12 status of weaners in autumn and spring and calves in early summer and increased the selenium status of weaners during both spring and autumn. This study has highlighted the complementary role of forage herbs in improving growth and maintaining trace element status of farmed deer. Keywords: chicory, plantain, copper, vitamin B12, selenium, weaner deer
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(93 KB)
Adoption of new technologies or management systems on sheep and beef farms is a complex business. Multicriteria decision making (MCDM) methods provide a quantitative means to assist with decision making where there are multiple and conflicting goals measured in different units. The MCDM process consists of a series of stages from defining the problem to identifying the best alternatives. In a study investigating the adoption of beef production technologies, seven sheep and beef farmers from throughout New Zealand were confronted with a choice of improved or new systems for their beef production operations. Suggested systems had gross margin values calculated for them. The MCDM tool was then used to rank the new systems in order of preference. The farmers decided what criteria were important to them in making decisions. They then scored each system for each of the criteria, and decided on the importance of each criterion relative to other criteria. An overall ranking for each system was calculated using this information. Across all seven case studies, profit and issues directly related to profit made up less than half of the contribution to the top ranked system. In two cases, it contributed less than 20% of the total. Other criteria included sustainability, management complexity, labour requirements, family needs, impacts on pasture quality control and input costs risk. In nearly half of all cases, the most profitable option was not the preferred option when all criteria were considered. Keywords: multiple criteria decision making, farm systems, beef, decision making
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(148 KB)This project was undertaken to examine how people in the North Island of New Zealand might evaluate a variety of rural and agricultural landscapes and the criteria that they used to make their assessment. Between November 2004 and March 2005 a convenience sample of 50 people were interviewed from around the Waikato, Auckland and Bay of Plenty. The interviewers asked people to sort and discuss 54 photos of natural landscapes containing a range of vegetation types. All the photos were standardised to a similar composition to assist in the comparisons. Each person being interviewed was asked to sort the photographs into categories reflecting their own criteria and then explain the categories. They were then asked to identify their most and least preferred categories. The most preferred vegetation types were the indigenous forest types which were considered “inspiring” and “attractive”. Well grazed grasslands were moderately preferred as being “natural” and “well managed”. Cropped areas were disliked by some people for being “over controlled”. The least preferred were gorse blocks and regenerating scrubland which were considered “ugly” and “messy”. Keywords: landscape, policy, ecology
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(138 KB)In Pohangina Valley, near Palmerston North, subdivision over the last 30 years has created a mix of large sheep, beef, dairy and deer farms, lifestyle blocks and village housing lots. For the Valley, like many other New Zealand rural communities, this has lead to a diversity of perspectives and tensions between some residents over subdivision and land use. A number of these issues were exposed at a workshop held as part of a “Project Pohangina” Community Conference. Key issues for participants were a desire to maintain the Valley’s beauty, natural features and views, keep population density synchronised with available infrastructure, restrain ad hoc subdivision and buildings, control weeds, pests and unlimited tree plantings, protect farm profitability and maintain private property rights. Identification and reconciliation of these potentially conflicting goals by rural communities highlights some of the challenges of maintaining a vibrant community in a productive farming landscape. Keywords: subdivision, rural communities, land use tensions
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(79 KB)Lone Star Farms, which was formed in 1996, is not a corporate farm in the classical sense, but a family farm run on corporate lines, currently comprising 10 properties throughout the South Island. Four of these properties are partially pastoral leasehold, five are freehold, and one is Puponga Farm Park at the base of Farewell Spit in NW Nelson, which is leased from the Department of Conservation. We are solely a sheep and beef cattle enterprise, with a geographic range which gives a good spread of climatic and market risk. Last winter we carried approximately 128,000 sheep and beef cattle stock units, and we are budgeted to increase next year to 140,000 su. There are nine Farm Managers and generally 20 other permanent farm staff. We have a Head Office, situated in Nelson, which, on the farming side of the business, consists of one Operations Co-ordinator and the equivalent of 2.5 administrative and clerical staff, giving a ratio of one farm staff member to 4600 su, and one support staff member to 40,000 su. The first consideration once we assume ownership of a property is to address subdivision, soil fertility, pasture species, and animal genetics, and once these are taken care of, we begin utilising our management strengths. In terms of Land, Labour, and Capital, it is the Labour component (i.e. managerial expertise regarding timing, decision-making and control) which will take us forward, once the basic building blocks of productivity are in place.
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(70 KB)In agricultural research, development and extension (RD&E) the importance of building partnerships between technology collaborators (e.g. farmers, researchers, extension, industry) is widely accepted. The FutureDairy project has formalised relationships and interactions between farmers, researchers and advisors to ‘co-develop’ knowledge and technologies that address key industry challenges. Separate industry partnerships have been established to study opportunities in forages, feeding and labour saving innovations. Reflections on these partnerships, and their performance to date, suggests there may be benefit in knowledge partners having a better understanding of expectations for the partnership. Also highlighted is the way in which a technology codevelopment approach, though suited to developing guidelines for managing new technologies, may not be suited to systems questions. Issues that require multiple technologies and knowledge types to be addressed appear, from our experience, to require a different form of partnership than those used for developing new technologies. Without an understanding of these principles, RD&E organisations may still fail to deliver on industry expectations even while they are encouraging greater industry participation. Keywords: knowledge partnerships, co-development, feeding systems, complementary forage rotations, multidisciplinarity, partner farms, farming systems research project.
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(105 KB)
This study investigated companion crops and time of sowing of a herb (chicory and plantain) and clover (red and white clover) mix in dairy pasture systems. Five summer crops (turnip, rape, turnip-rape, radish and millet), sown alone or in combination with herb/clover in spring 2003, were compared over the first summer. Dry matter (DM) production was higher for millet and rape than turnip-rape or radish. Metabolisable energy (ME) content of millet and turnip was lower, and neutral detergent fibre (NDF) content of millet higher than all other crops. Inclusion of herb/clover reduced ME and increased NDF at the second grazing. In autumn 2004, an Italian ryegrass + herb/clover mix was direct drilled into plots without the spring sown herb/clover mix, and Italian ryegrass only into the remaining plots. The spring sown herb/clover system resulted in higher herbage DM at the first grazing (June 2004) after sowing Italian ryegrass, but lower production in spring 2004 than the autumn sown herb/clover system. There were no differences in DM production at any other grazings. In winter and spring 2004, ME was higher for autumn than for spring sown herb/clover. Crude protein content was higher for autumn sown herb/clover in June and July than for spring sown, but lower from December 2004 to April 2005. From September 2004 to August 2005, the NDF content of spring sown herb/clover was lower than for autumn sown. Throughout the study, both chicory and plantain content (%DM) was higher and weed and dead matter lower, with spring compared to autumn sowing. Keywords: herbage production, chicory, plantain, metabolisable energy, weed suppression
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(174 KB)Continued improvements in home grown forage consumption are needed to support the long-term profitability of the dairy industry in southern Australia. Most home grown forage currently comes from perennial ryegrass pastures, which have significant limitations in the southern Australia environment. These limitations threaten future productivity gains, and we therefore consider opportunities for using other plant species. Data on the production of alternative perennial grasses, brassica summer crops, C4 summer crops and winter cereals grown for whole-crop silage are limited and generally show large variation in yields between sites and years. Simulation models suggest that, once the base ryegrass pasture is well-utilised, incorporating complementary forages can return $70 - $100/ha extra operating profit for every additional tonne of home grown forage DM consumed per ha. Double cropping (winter cereal or annual ryegrass followed by a summer crop of turnips or maize) and summer-active pastures such as tall fescue show particular promise. Further information is required on how to integrate these forages into whole farm feeding systems to realise the additional profit with manageable business and environmental risk. Keywords: dairy systems, forage production, pastures, forage crops, simulation models
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(110 KB)We used modelling to test the hypothesis that rotation length based on the emergence of three live leaves per ryegrass tiller (3-leaf principle) would result in greater pasture production, and increased milk production and profit per hectare than rotations based on standardised decision rules (best management practice; BMP). This hypothesis was tested using a computer program designed to model the interactions between climate, paddocks, animals and management policies. The model was set up for a farmlet (Strain Trial, Herd 1, 04/05 season) and simulated over 10 different climate years (93/94-02/03), two different sets of rotation lengths (3- leaf and BMP), and over a range of comparative stocking rates (85 – 100 kg Lwt/t DM). Average return on assets (ROA) was measured with random price sets drawn for milk, the variable cost of purchasing silage, and land appreciation rate. For the systems and climate years tested in this exercise the model predicted a greater (P<0.05) average ROA for BMP rotations compared to 3-leaf rotations (9.85 and 9.73%/year, respectively). The 3- leaf rotations resulted in a small (P<0.001) increase in pasture grown (0.17±0.02 t DM/ha). However, BMP scenarios were more profitable because of greater annual milksolids production per hectare (1%), mainly achieved during peak lactation. The 3-leaf principle showed benefits in the second half of the season, but this could not compensate for the earlier loss in production. Keywords: dairy farm system, grazing management, rotation length, whole farm model.
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(215 KB)Mixed species pastures typically have insufficient clover to capture its high nutritional value as extra milk production. This paper reports interim results of a study investigating novel methods of presenting white-cloverrich diets to cows. Cows were offered continuous, free access to grass and clover growing separately side-byside in the same paddock (G/C), or grass-only at night between the afternoon and morning milking and cloveronly during the day between the morning and afternoon milking (GnCd). These treatments were compared against controls of grass-only pasture (Grass) and mixed grassclover pasture (Mix; 92% grass, 8% clover). Cows offered G/C or GnCd produced 2.0 and 1.9 kg MS/cow/ day, respectively, compared with 1.5 kg MS/cow/day for cows grazing Grass and Mix. The AM and PM milkfat of cows grazing G/C contained high levels of skatole, an indicator of protein digestion and metabolism, compared with Grass and Mix. For GnCd, levels were high only in the PM milk and low in the AM milk following the grass-only diet at night. The GnCd cows grazed proportionately more during the ‘day’ and less at ‘night’ than the G/C cows. Manipulating the spatial and temporal allocation of grass and white clover to align nutrient allocation with the nutritional and behavioural needs of the cow boosts MS production, but there is scope to improve the efficiency of protein utilisation in the rumen. Keywords: grass, white clover, milk production, grazing behaviour, skatole
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(98 KB)A comparative study of cows grazing grasses differing in soluble sugar content was undertaken to explore whether sugar content improves ruminal plant protein utilisation and influences milk flavour chemistry. Lower concentrations of ammonia, and amino-acid degradation products including the flavour compounds skatole and indole were observed for rumen contents sampled from non-lactating fistulated cows grazing high sugar ryegrass relative to samples from cows grazing Italian or a standard perennial ryegrass, suggesting improved plant protein nitrogen utilisation in response to the high sugar grass diet. Concentrations of plant protein fermentation products in the rumen of the fistulated cows were significantly higher at noon, compared to morning and afternoon values. In milk collected twice daily from the lactating cows grazing the above ryegrass varieties, no differences in yields of milkfat or skatole were detected between cows fed the different grass varieties. However yields of skatole in milkfat were two times higher in afternoon than morning milk. The rumen response to morning feeding appears to influence the flavour chemistry of afternoon milk. Keywords: rumen metabolites, milkfat skatole, indole, perennial ryegrass, Italian ryegrass, water soluble carbohydrate
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(88 KB)
Feral animals such as possums are known to utilise pasture as a substantial part of their diet, with individual animal intake rates well quantified. The objective of this study was to quantify this effect in terms of pasture accumulation rates, in areas where these animals are likely to occur in high densities; i.e. the boundaries between native forest and pastoral farms. Pasture accumulation rate was measured in small plots open to feral grazing and plots excluded from grazing with electrified flexinets, at six sites throughout the Waikato. Three further sites, within possum control schemes, were established as controls. Pasture accumulation rates were significantly greater within the exclosure plots at all six uncontrolled sites, by ~3 kg DM/ha/d in late-winter and ~7 kg DM/ ha/d in late spring. In contrast there were no significant differences between open and exclosure plots at the three sites where there was active possum control. This effect is quite substantial in the context of livestock consumption, though is not entirely reconcilable with predictions based on possum intake and diet studies. It nevertheless represents a source of loss which is easily countered, with additional benefits in terms of lowered Tb risk and improvement of native vegetation condition. Keywords: feral grazing, grazing exclosure, pasture accumulation rate, possum diet
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(100 KB)In the potential paddock subdivision of a large property, a simulation study shows a rapidly increasing total fencing requirement as paddock shapes depart from square to rectangular, with it being 6% greater if length to width ratio is 2:1 and 25% when 4:1. It is similar or slightly less for a hexagonal shape with some advantages from machinery or animal behaviour considerations. Fencing a triangular shape would be 21% greater. Provision of access lanes to all paddocks simplifies management. While a series of ring lanes plus a few connecting lanes in square paddock design increases total fencing by 30% as compared to 25% for a central lane plus laterals lanes, it does result in a 9% reduction in the mean distance (time) needed to move stock between paddocks. Keywords: fencing; subdivision
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(144 KB)Farmers are increasingly using management systems such as moving cows out of paddocks onto stand-off pads to protect wet soils from damage during winter. Studies were carried out to investigate nutrient and faecal bacterial retention or loss from stand-off pad materials. A preliminary laboratory study found that a range of natural materials, including crushed pine bark, wood chips, zeolite and soil can retain between 66% and 76% of applied cows’ excreta nitrogen (N). Zeolite was found to be particularly good at reducing ammonia (NH3) volatilisation losses from the columns. A field-scale standoff pad study at a Waikato dairy farm, in the winter season of 2005, indicated that carbon (C)-rich materials including both bark and sawdust can be used as standoff pad materials with effective retention of N and faecal bacteria. Both bark and sawdust pads retained about 60% of deposited excreta N. Substantially more Escherichia coli were recovered in the drainage from the bark pad (total yield 3.1 x 1011 E. coli) than from the sawdust pad (total yield 7.5 x 109 E. coli) demonstrating that sawdust was more effective than bark in retaining these faecal bacteria. Keywords: stand-off pads, winter management, dairy, nitrogen, faecal bacteria, natural materials
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(197 KB)Poor performance of white clover in the current climate of innovation farm management practices has become problematical, particularly within the dairy industry. There are as many grazing management systems as there are farmers and management guidelines can only be broad generalisations at best, with little interpretive value in the face of the multitude of options available and variables recognised and unrecognised. The principles of plant growth are used to interpret grazing management strategies in order for farmers to have greater understanding of their pastures and determine for themselves what the expectations and outcomes of various management strategies may be. This is of greater relevance to the dairy industry where innovative changes (pasture covers, grass cultivars, pasture renewal and establishment techniques, fertiliser N) can combine to produce a ‘clover unfriendly environment’. Keywords: competition, fertiliser N, grazing management, light, management systems, plant growth, protection, space, white clover.
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(68 KB)The recent invention of Herd Homes has presented NZ dairy farmers with a flexible facility for feeding and standing-off stock especially during wet periods. Herd Homes are a combination of feeding platform, stand-off facility and animal shelter comprising a “greenhouse” type roof over slatted concrete floors with an underfloor manure bunker. The prototype Herd Home built in Northland for 230 cows was closely monitored during its initial year (2002/03). Different bunker media were evaluated for their ability to absorb and retain manure nutrients. The media tested were natural materials (soil, wood shavings and a combination of soil/wood shavings) that were all effective at capturing nutrients (N and S) from the bunker manure. Benefits of media amendments are greater nutrient enrichment of the final bunker manure making it more useful for subsequent land application. Use of soil as a bunker medium appears to be the most viable and cost effective option. In early 2006, manure samples were collected from Herd Home bunkers from four geographically diverse areas of NZ and analysed for nutrient content. Nutrient concentrations found reflected variability in cow numbers, usage and feed inputs. In November 2004, 10 existing Herd Home owners were surveyed as to their reasons for purchase. The farmers reported ease of farm management, “on-off” grazing, reduced pugging damage, and improved stock condition and production were some of the beneficial effects of Herd Homes. Keywords: Herd Homes, winter management, wintering system, stand off, feed pad, manure management, bunker manure
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(79 KB)Winter is a very important period during the dairying calendar. Regions such as Southland, with susceptible soils and extended periods with soils at saturation levels will face increasing pressure to review wintering practices. On-farm options for wintering cows to protect soils and prevent pasture damage are needed. This requires a turn-around in philosophy from taking cows to pasture/crops, to bringing supplementary feeds to cows. Specialised facilities exist such as feed pads, stand-off pads, wintering barns or Herd Homes. The advantages of such systems are reduced pugging and compaction of soils, better pasture growth and stock condition. Disadvantages may include requirements to upgrade effluent management systems to cope with more concentrated waste streams. Research has shown that pasture production can be increased by withholding stock from soils during sensitive periods. Advantage should be taken of this to fully feed stock in specialised facilities. However, cow welfare and effluent management must be prioritised to maximise the wintering benefits. Keywords: stand-off pads, bedding materials, soil pugging, Herd Homes
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(78 KB)Mowing trials were carried out to determine the rates of fertiliser nitrogen (N), phosphorus (P), potassium (K) and sulphur (S) and frequency of application of K for maximum pasture production on extremely infertile humped and hollowed pakihi soils in the Grey Valley (Souters and Sommervilles dairy units), and flipped soils at Cape Foulwind (Bassetts dairy unit) under high annual rainfall (2000 – 3000 mm) on the West Coast. In the first measurement year, there was no significant increase in pasture production above 480 kg N/ha, 56 kg P/ha, 360 kg K/ha and 136 kg S/ha at Souters and Bassetts and a significant increase in pasture production up to 600 kg N/ha, 56 kg P/ha, 360 kg K/ha and 140 kg S/ha at Sommervilles. In the second year, there was no significant pasture production increase above 480 kg N/ ha, 56 kg P/ha, 360 kg K/ha and 136 kg S/ha at all sites. The high N, K and S rates were required because nutrients were not being recycled through returned clippings. This situation would be similar to the early stages of dairy management on these units where only a small proportion of pasture would receive recycled nutrients through return of excreta. Over time, a larger proportion of the pasture would be affected by excreta and fertiliser nutrient requirements would be expected to decrease. There was no increase in pasture production from applying potassium chloride in more than four applications per year at Souters and Bassetts in the first year, but a significant increase in pasture production from eight compared with four applications per year at Sommervilles, where soil QT (quick test) K levels were lower than at the other two sites. Keywords: flipped, hump and hollowed, nitrogen, phosphorus, potassium, sulphur
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(127 KB)While it is true that leaching is usually not a strong pathway for phosphorus (P) loss under many systems, is it true for all? Two studies reported in this paper sought to establish if significant phosphorus leaching can occur under normal pastoral production systems. Undisturbed-core lysimeters collected from a Wharekohe silt loam from Northland were treated with fertiliser P (reactive phosphate rock and superphosphate) then leached from August to November, 2005. In a second study, soil profiles under pasture for sheep/beef and dairy production in the catchments of the Rotorua lakes were sampled to depths of 1.5 m (28 sites), and soil Olsen P and P retention capacity index were determined down these profiles. Phosphorus losses from the Wharekohe soil to 25 cm depth were up to 33% of the P applied (superphosphate applications of 50 and 100 kg P/ha). Some Rotorua soils displayed enriched P concentrations at depth (to 1.5 m), often coupled with moderate or low P sorption capacities. If connectivity exists between leaching pathways and surface water bodies these observations indicate that alternative management strategies need to be developed and adopted for soils that leach significant quantities of P. The Wharekohe silt loam is one such soil. Keywords: phosphorus, leaching
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(97 KB)Poplar trees serve a wide variety of purposes on New Zealand farms. Their high growth rate and ability to establish from poles make them a very suitable tree species for soil conservation plantings on erosion-prone hill pastures. The impact that such plantings have on understorey pasture production as the tree canopy develops in size was determined by measuring pasture dry matter (DM) production on three North Island sheep and beef hill farms. Poplars markedly reduced annual pasture production by up to 50% at high canopy closure. To maintain pasture production at 65-75% of uneroded open pasture, poplar canopy closure should not exceed 50%. However, it must be emphasised that the loss in production through soil erosion (e.g. slips or earthflows) without poplars can be even greater, more permanent, and much more unpredictable. Keywords: Populus, soil erosion, agroforestry, digital images, canopy closure, understorey pasture
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(206 KB)Two trials were set up near Te Awamutu and Ashburton to explore the difference in pasture responses between standard urea and Agrotain treated urea (SustaiN) over a 12 month period. Two rates of nitrogen (N) application were used (30 kg N/ha and 60 kg N/ha) and the fertilisers were applied four times throughout the year (once each “season”). At the 30 kg N/ha application rate (120 kg N/ha total), N responses with SustaiN were 75.2% higher than with urea alone. At the 60 kg N/ha application rate (240 kg N/ha total), N response with SustaiN was 33.7% higher than urea alone. Similar seasonal and annual responses occurred at both sites. Economic analyses showed these increases in response to be very profitable and indicate that there is considerable potential for improving farm production and profitability by treating urea with Agrotain. Keywords: nitrogen, urea, Agrotain, pasture, response, efficiency
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(81 KB)
Two experiments were conducted in sodium deficient (<0.03% Na in DM) pastures on steep, south facing slopes at Mt Grand, Hawea, Central Otago (600 m.a.s.l), to determine the effect of the application of coarse salt (NaCl) fertiliser on pasture composition and establishment of oversown seeds. In Experiment 1, factorial combinations of salt (0, 150 kg NaCl/ha), N (0,100 kg N/ha as urea) and sulphur superphosphate (0, 500 kg/ ha) fertilisers were applied to 30 x 8 m plots in early December 2003. Balansa clover (10 kg seed/ha) and subterranean clover (10 kg/ha) seeds were oversown into each plot in March 2004. Plots where salt was applied were grazed intensively by Merino ewes immediately after salt application creating up to 50% bare ground. In December 2004, pastures where salt had been applied one year earlier were shorter, had a lower percentage of white clover and a higher percentage of bare ground and balansa clover. In Experiment 2, factorial combinations of salt fertiliser (0, 100 kg NaCl/ha) and seed (no seed, mixture of Caucasian clover (10 kg/ha), Lotus pendunculatus (2 kg/ha) and plantain (2 kg/ha)) were applied together to 5 x 10 m plots in September 2004. In April 2005, pastures where salt was applied were shorter, had fewer grass seedheads, a lower percentage of resident grasses and litter but a higher percentage of bare ground and plantain. There were more seedlings of plantain where salt was (6.5 seedlings/m2) than where it was not applied (1.1 seedlings/m2). This small plot work indicates that salt fertiliser application to Na-deficient herbage can enhance grazing intensity. By creating soil disturbance and reducing competition from resident grasses, salt application increased the establishment of oversown seeds of plantain and balansa clover. Establishment of the slow growing species (Caucasian clover, lotus) and the large seeded subterranean clover appeared to be unsuccessful under the conditions of the experiments. Salt application is a tool for pasture management and improvement in the hill/high country that could be used together with other methods such as herbicides, seeding, sub-division, grazing management and fertiliser. Keywords: grazing, sodium, oversowing, hill country
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(82 KB)The prevalence of annual clover species and white clover (Trifolium repens) during the critical late winter to early summer period (mid Aug – Dec) are compared in relation to aspect, altitude, temperature and rainfall on Mt Grand at Hawea Flat. Measurements were at four north facing sites (450, 620, 750, 910 m a.s.l.) and one shady site at 630 m a.s.l. The rainfall was similar for all altitudes and aspects but annual clovers dominated on sunny faces and the perennial white clover dominated on the shady face with suckling (T. dubium) the only adventive annual clover present. Annual cluster clover (T. glomeratum) dominated on the lower sunny faces at 450 and 620 m and sub clover (T. subterraneum) dominated at 750 m. Suckling and striated clover (T. striatum) were present on all sunny aspect sites and were unaffected by altitude while haresfoot (T. arvense) presence increased with altitude. Air thermal time accumulation for the mid Aug-Dec period was 1440 °Cd at the 450 m site and declined at 100 °Cd per 100 m of elevation (r2 = 0.99). Thermal time at 910 m was <1000 °Cd and may limit seed production of some annual clover species at or above this altitude. The dominance of adventive annual clovers on the sunny aspects indicates areas that are probably suitable for introduction of improved annual species such as balansa clover (T. michelianum) or modern cultivars of sub. Productivity of perennial white clover which has persisted on the shady faces may be increased by more intensive grazing management. Keywords: altitude, aspect, hill pastures, rainfall, spring production, thermal time, Trifolium arvense, T. glomeratum, T. dubium, T. repens, T. striatum, T. subterraneum.
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(159 KB)Two trials were designed to provide baseline data on the productivity and quality of irrigated pastures in the Intermountain West USA. An initial clipping trial (1997- 1999) screened a number of temperate grass-legume mixtures well-adapted to the soils and climate of the Intermountain West, and a successive grazing trial (2001- 2003) evaluated a subset of these mixtures under rotational grazing. The most productive and best utilised grass in mixtures was meadow brome (Bromus riparius), followed by tall fescue (Lolium arundinaceum) and cocksfoot (Dactylis glomerata). Perennial ryegrass (Lolium perenne) and Kentucky bluegrass (Poa pratensis) mixtures tended to become legume-dominated (up to 44% under grazing), and were therefore high in quality but a potential bloat threat. The bloat-safe legume birdsfoot trefoil (Lotus corniculatus) proved to be productive, well-utilised, and as persistent as other legumes in mixtures under grazing. Keywords: grass, grazing, Intermountain West USA, legume, mixtures, pasture
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(94 KB)The purpose of this study was to conduct a preliminary investigation into the effect of increasing fertiliser- and excreta-N inputs on the spatial distribution and rate of potential nitrification activity in hill country pasture land at two sites, Invermay and Ballantrae. High nitrification rates could potentially limit N efficiency by increasing N losses through leaching and denitrification. Nitrification potentials (NP) were measured in camp sites and medium slopes of hill country soils receiving 0 kg N and 500 kg N/ha/yr over the previous 18 months. Nitrification potential was determined by calculating the rate of nitrate production (mg NO3-N/kg soil/h) by linear regression of soil solution concentrations, versus time. Nitrification potential was significantly higher at Invermay than at Ballantrae, which was likely due to a significantly lower soil pH at Ballantrae. At Invermay, NP increased with fertiliser-N application rate and in camp site soils. The fertiliser N effect was not observed at Ballantrae. However, soil NO3-N and NP was significantly greater in soils from camp sites than for soils from medium slopes. Best management practices for fertiliser-N application in hill country should make allowances for these factors to maximise farm efficiency and profitability. Keywords: hill country, nitrification potential, nitrogen fertiliser, stock behaviour, excreta-N, mineral-N, New Zealand
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(84 KB)Sulphur trials were carried out in the hill and high country of the South Island from 1986/87 to 2000/01. Initial trials showed that sulphur fortified superphosphate fertilisers are more effective products than fine elemental sulphur and sulphur bentonite prills, both in terms of dry matter production and cost effectiveness. This is because Sulphur Super products contain sulphate sulphur and finer elemental sulphur. Sulphur Super Extra (28% S) was more effective in the short to medium term than Maxi Sulphur Super (50% S) largely because it contained more sulphate sulphur. It would be a more preferable option for development, particularly when used at above maintenance rates. It is preferable to apply these products on a biennial rather than a triennial basis to maximise dry matter, maintain better sward composition and to improve the chances of coinciding application with better growth conditions, most notably summer rainfall. Residual elemental sulphur oxidises with time, reducing the dependence on biennial application, although there is still a risk of temporary sulphur deficiency and a delay in response of clover to follow up topdressing if topdressing is left beyond 2 years. Herbage sulphur levels, in conjunction with observation of pasture composition and vigour are useful to indicate when sulphur fertiliser needs to be reapplied. Keywords: sulphate sulphur, elemental sulphur, sulphur bentonite prills, wet mix Sulphur Super, Maxi Sulphur Super, anaerobic nitrogen
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(389 KB)
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