Clover root weevil (Sitona lepidus) is established in Auckland, Waikato and Bay of Plenty provinces. A pasture survey in 1997 estimated that the rate of its spread at about 35 km annually. Adults feed on the foliage and larvae on roots and nodules of white clover. Pasture populations appear to be 10 times higher in New Zealand than in the UK. New Zealand’s temperate climate and high clover content in pastures may offer a very favourable environment for S. lepidus, with serious implications for New Zealand’s pastoral farming. Keywords: clover root weevil, pasture pests, Sitona lepidus, Trifolium repens, white clover
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(42 KB)“Population, Pasture, Production and Profit” is our theme. In seeking a definition for “population” I found one for “population explosion.” It was described as a condition that converts spots of beauty into amusement parks. Take heart though, a “city” was defmed as “The abiding place of wealth and luxury.” So if the city gobbles up our land, perhaps we have something to look forward to.
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(15 KB)In February 1996, 48 Friesian and Jersey cows grazed pastures containing nominally 0, 25, 50 or 75% of dry matter (DM) as white clover with the balance mainly C4 grasses at either ad lib. (50 kg DM/cow/day) or restricted (25 kg DM/cow/day) allowances. The aim of the trial was to measure the effect of clover content on milk yield and composition, and to determine the optimum clover content for milk production. Milk yields of cows on the ad lib. allowance grazing 25% clover were 22% higher (P<0.05) than yields of cows grazing 0% clover. Milk yields on 50 and 75% clover were similar, 33% higher (P<0.05) than for cows grazing 0% clover. The differences were similar for cows on the restricted allowance. Clover content had little effect on milk composition except for a decrease in fat % with increasing clover content. The trial showed increased milk yields were owing to both increased intakes associated with high clover diets, and the higher nutritive value of the clover. Results showed that a clover content of 50% is a realistic target to increase milk yields considerably. Increasing clover content above 65% would do little to increase milk production further. Keywords: Friesian cow, herbage intake, Jersey cow, milk composition, milk yield, nutritive value, perennial ryegrass, smooth witchgrass, summer grass, white clover
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(49 KB)Rural subdivision in South Auckland is influenced by four characteristics: 1) the change in lot sizes and the economic viability of land uses; 2) activity conflict between lifestylers and rural production activities; 3) the value of land for the proposed land use; 4) the costs and benefits associated with subdivision proposals. Rural subdivision has the potential to change the landscape, land uses, the rural environment and the community. Currently the area is made up of rural activities with an increasing number of rural residential activities encroaching into the rural area of south Auckland. Keywords: amenity, economics, land use, land values, rural environment, rural subdivision
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(15 KB)The Counties District has traditionally been regarded as the food bowl of Auckland. Its high quality land resources, equitable climate and proximity to markets have and are still playing an important part in producing milk, vegetables and meat all year round. However, as Auckland continues to grow and people continue to want to live and pay to live in a rural environment the character and future of this food producing bowl is under threat. Keywords: Auckland, Counties District, land use, urban expansion
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(39 KB)During spring 1995, pastoral farms in the Raglan– Franklin districts were surveyed to establish their trace element status. The major soil groups of the area were identified and a geographically representative sample of farms within these soil groups sampled for soil and pasture trace element concentrations. In total, 82 sites on 40 farms were sampled. In addition, liver samples from 80 lambs on 20 of these properties were analysed for trace elements during summer of 1995/96. Soil samples were analysed for Mn, Cu and Co; pastures were analysed for Mn, Fe, Zn, Cu, B, Mo, Co, Se and I. Lamb livers were analysed for Cu, Se and vitamin B12. Survey findings indicated that the Co concentrations in soils, pastures and vitamin B12 in lamb livers throughout much of the district were marginal, particularly in the southern area. The two soil groups most at risk were the yellow-brown loams and yellow-brown earths. Farmers are advised to closely monitor their Co status during late spring and to consider their grazing management strategies. Generally, the status of other trace elements was satisfactory. Keywords: lambs, liver vitamin B12, pasture cobalt, soil cobalt, soil contamination, soil group, titanium, trace elements
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(69 KB)
In the area from Taupo to Auckland, and North Island wide, BOP Fertiliser Ltd, Mt Maunganui, supplies some 700 000 t of fertiliser annually. In the years 1994/95, 1995/96 and 1996/97 total fertiliser sales were 668 900, 700 700 and 678 100 respectively. BOP Fertiliser supplied fertiliser to approximately 50% of New Zealand dairy farms. Nitrogen was applied to 91% of dairy farms at an average annual input of 58 kg N/ha. Less than 4% of farms applying N received >200 kg N/ha. Some 23% of dairy farms received less than maintenance P (30 kg/ha). A review of soil fertility levels on dairy farms in 1996/97 using soil test results from the Soil Fertility Service laboratories at Ruakura suggests some 38% of Olsen P values on dairy farms were below optimum (<30), 49% of pH tests were <5.8, 55% of K tests were <8, 30% of S tests were <12 and 8% of Mg tests were <15. Likewise on sheep–beef farms some 43% of the land received less than maintenance P (15 kg P) while soil fertility levels indicated 54% of Olsen P values were below optimum (<17); 69% of the pHs were <5.8; 42% of the K tests were <5; 29% of the S tests were <8 and 12% of the Mg tests were <8. Figures for South Auckland follow a similar pattern to the region. Trace element use indicated 26% of the farms used Co, 37% used Se, 13% boron and 9% copper. Pasture analyses records for 1996/97 (Ruakura SFS Laboratories) suggest trace element use follows deficiencies in a general way. Keywords: database, dairy farms, fertilisers, nutrient status, sheep–beef farms, trace elements
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(40 KB)Nitrogen (N) balances were constructed for “average” dairy farms in New Zealand, south west England and The Netherlands, and for Dairying Research Corporation (DRC) farmlets varying in stocking rate and use of N fertiliser and maize grain. N surpluses were calculated to indicate the potential impact on the environment and these were compared with measured N losses from the DRC farmlets. On the average New Zealand farm, annual N inputs of 186 kg N/ha/year (mainly from N2 fixation) resulted in N outputs in milk+meat of 55 kg N/ha/year (30% efficiency) and a N surplus of 131 kg N/ha/year. Dutch farms produced 70% more milk/ha but had N inputs of 568 kg/ha, N outputs in produce of 81 kg/ha (14% efficiency) and a N surplus of 487 kg/ha. English farms were intermediate. In the DRC farmlets, applying fertiliser N at 400 kg N/ha/year increased N surpluses and nitrate leaching by 3–4 fold, resulting in nitrate-N concentrations in drainage of 2.5× the recommended maximum for drinking water. The most efficient farm system received no N fertiliser and was highly stocked (3.3 Friesian cows/ha) for very high pasture utilisation. This resulted in similar milk production/ha to Dutch farms (with 1/3 the N inputs) and a 45% efficiency of conversion of N inputs from N2 fixation into milk and meat products. Keywords: dairy farm, nitrate leaching, nitrogen balance, nitrogen fertiliser, stocking rate
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(51 KB)Nitrogen (N) fertilisation plays an important role in Swiss grasslands, not only as a production factor but also as an ecological criterion determining direct payments for farmers. N fertiliser use reflects this duality and the grassland-based milk production is influenced by the sustainable type of approach. For comparable milk yields per cow, 4–6 times less concentrate feed is used and 7–9 times less artificial N is applied per ha of forage land than in the main milk producing regions of Western Europe. Grassland fertilisation is based primarily on farm-produced slurry, which is carefully stored and spread on grassland. Consequently, the average N balance surplus (= risk for pollution) on intensive Swiss dairy farms is as low as 109 kg N/ha/year compared to over 400 kg in high input areas like The Netherlands. In good grass production regions in the Swiss lowlands, 20 kg DM could be gained per kg additional N. However, the permitted level of N use is low in Switzerland. In addition to the slurry N, only 25–50 kg artificial N/ha/year can be applied to grassland. The Swiss farmers receive high direct payments (about $NZ1000/ha) from the state for applying a strictly environmentally friendly farming system. Keywords: dairy farming, environment, grassland, nitrogen budget, nitrogen fertilisation, sustainable agriculture
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(47 KB)A database of sulphur (S) fertiliser trials was analysed to determine the effect of different fertiliser application times, frequencies and forms on S response. Yields were about 6% higher when S was applied in spring than autumn on highleaching sites (free-draining, high-permeable soils with high rainfall), and about 4% higher when S was applied in autumn on South Island soils. Pasture yield was about 6% higher when S was applied as a split application than as a single annual application, with the advantage to split applications also tending to be higher on high-leaching soils. The application of S had a small residual affect on S soil test after one year, the size of the residual being dependent on fertiliser rate and season of application. In contrast, a once-only application of S could increase yield above that in the control treatment for at least 3 years after S was applied such that the response in the second and third years was about 0.5 and 0.25 times that in the first year. The residual effect on yield, the effect of applying different fertiliser rates, and previous fertiliser history have been incorporated into decision support software for calculating fertiliser S responses by calculating an effective fertiliser rate using an exponential weighted moving average. However, a standard response curve for determining the relationship between relative yield and effective fertiliser rate had to be used, as a site specific curve could not be predicted from data in the S database. Keywords: fertiliser, model, pasture yield, sulphur
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(44 KB)Nitrogen balances (inputs minus outputs) were calculated for 5 dairy farms, 5 orchards and a range of crops. All the balances were positive, i.e., surplus N was present and a proportion of this N will eventually reach the groundwater as nitrate. On a per ha basis, the greatest N surplus was from early potatoes > winter cabbage, winter lettuce and squash > dairying, kiwifruit, summer cabbage and summer lettuce > pumpkins, onions and main crop potatoes > dry stock farming. The area in each activity was multiplied by the surplus N factor to obtain the potential contribution of N to groundwater in the Pukekohe area. Early potatoes (217 t N), contribute much more than onions (105 t N), dairying (59 t N) or dry stock farming (57 t N). Other activities contributed < 30 t N each. Winter crops had higher surplus N levels than the same crop grown in summer because winter crops had higher fertiliser N inputs and lower crop off-take of N. Management practices contributing to the N surpluses include high rates of N fertiliser used on some crops; a long history of cultivation, which has reduced soil organic matter contents and the ability of these soils to immobilise mineral N; and nil to intermittent use of cover crops to retain N in the topsoil. Keywords: aquifers, dairying, fertiliser, groundwater, land use, management, nitrate, nitrogen balance, nitrate leaching, vegetables.
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(30 KB)
Decision support software for the evaluation of phosphorus (P) and sulphur (S) fertiliser strategies can assist farm consultants and their clients to determine pastoral agriculture fertiliser policies. The underlying dynamic model is based on the P and S cycles in the soil–plant–animal system, including fertiliser inputs and soil- and animalmediated losses. Initial soil fertility is estimated from the Olsen P and phosphate-extractable organic S soil tests, and recent fertiliser history. In the S sub-model organic S and elemental S pools are considered. Animal production responses to fertiliser are estimated from relationships between soil P and S status, fertiliser inputs, pasture relative yield and stocking rate. Maintenance and economically optimum fertiliser strategies can be automatically calculated or the user can enter their own scenarios. Alternative fertiliser policies can be evaluated in terms of nutrient budgets, soil P and S status, pasture and animal production, and economics. Keywords: decision support, economics, fertiliser, model, phosphorus, sulphur
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(38 KB)Historically farmers made little distinction between farming for product or farming to maintain the physical resources for future generations but now have to demonstrate the latter. With this challenge, Federated Farmers, AgResearch, Livestock Improvement Corporation and Environment Waikato initiated study groups in the Waikato, linking farmers, scientists and policy agents. A case study of pugging (stock treading) management is used to demonstrate the group participatory process. The key stages in the group’s development over time are explained. Throughout these stages, exchange of principles, experiences, ideas and data about pugging were aligned to the group’s needs. Management guidelines to minimise pugging damage in both winter and spring were identified. The economic impact of pugging damage to paddocks was analysed at the farm level using UDDER. A comparative discussion of the group process compares the experiences of participants with published claims about study groups. Discussion of the group process calls for the need to develop methods for analysing group process. Keywords: decision-making, farm system, monitoring, participatory process, pugging, resource management, study groups
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(91 KB)Most modelling research into grazing management has focused on planning. However, if target outcomes for pastures, animals and profit are to be realised, planning and control must be closely linked. Control is required if actual outcomes are likely to deviate from those planned. This may be because of: variability in uncontrollable variables (e.g., the weather); imprecision in implementation (including timeliness); inaccurate measurement of outcomes (i.e., sensor errors); and errors in prediction during the planning process. A dynamic grazing system model was used with a genetic optimising algorithm to simulate the outcomes for different control strategies for a sheep farmlet. The optimum control sequencing for pasture allowance, nitrogen application, lamb drafting weight and supplementation was investigated. Optimum pasture cover levels were similar to those recommended to farmers, except for winter when higher allowances were suggested. Sensor errors for pasture measurement were shown not to have a significant financial cost to farmers if recommended measurement techniques are closely followed. Keywords: grazing control, grazing management, grazing system model, pasture measurement, system optimisation
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(66 KB)The AgLINK bulletin series dominated all agricultural and horticultural information publications from the late 1960s to the late 1980s, when it was discontinued. The collapse of such a high profile series raises questions about the viability of such a mechanism for linking farmers with facts. This failure highlights three key issues: the need to define and allocate the costs based on who benefits; the appropriate positioning of parties within the distribution chain; and a quality specification to which bulletins must adhere. We consider that AgFACT, the AgResearch pastoral agriculture information base which superseded AgLINK in 1997, should largely be cost neutral to science groups in AgResearch. However, the resources for providing information need to be met by science programmes, a cost which is outweighed by the opportunity to communicate with science stakeholders. The costs of distribution and retail need to fall with the other parties who benefit from the dissemination of this information – the retailer and the end user. We also consider that the role of AgResearch is in manufacture rather than sales to the public, which is best done by the agricultural service sector. AgFACT must maintain tight specifications, to ensure that it is relevant to farmers and other users, accurate and unbiased, and up to date. The penalty for not doing so is a loss of value and, moreover, a risk of it becoming a public liability. Keywords: AgFACT, AgLINK, agricultural information, information base, technology transfer
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(17 KB)Grasslands Challenge (Trifolium repens L.) white clover was developed to incorporate potential growth benefits, and disease resistance, in two double cross hybrids (Mediterranean × New Zealand) identified in evaluations at Kaikohe. Thirty-three elite selections of hybrids and New Zealand material were polycrossed for seed production. Progeny testing resulted in 27 parental lines with improved resistance to leaf disease and stem nematode (Ditylenchus dipsaci) relative to Grasslands Pitau. Testing of the maternal lines for seedling characteristics resulted in the deletion of one parent. A bulk line was evaluated in mini plots, and a hill country grazing trial, and showed improved growth to the control. In a grazing trial conducted in the Manawatu, Challenge showed outstanding winter production. The selection has a high stolon density in combination with a medium to large leaf size. This will allow Challenge to recover quicker from drought stress and grazing pressure. The plant type and early results indicate Challenge will be best suited to a rotational grazing management, particularly in regions where significant cool-season growth occurs. Plant Variety Rights were granted in 1997, and commercial seed should be available in 1998. Keywords: Grasslands Challenge, leaf disease, Mediterranean hybrids, stem nematode, Trifolium repens
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(41 KB)Two separate trials were carried out on different Northland soil types evaluating the most profitable nitrogen (N) product for use on wet soils. Each trial had three randomly allocated replicates of four treatments. The four treatments included ammonium sulphate nitrate (ASN), sulphate of ammonia (SOA), urea and a control. All treatments received one dressing of 30 kg N/ha in mid winter. On the Wharekohe silt loam trial, SOA was the most profitable product, providing extra feed for 4.2 cents/kg dry matter (DM). Urea provided extra feed for 6.3 cents/kg DM and ASN provided extra feed for 7.3 cents/kg DM. On the marine clay trial, urea was the most profitable product, providing extra feed for 9.6 cents/kg DM, compared with 13.8 cents/kg DM for SOA and 27.5 cents/kg DM for ASN. For both trials it was evident that the ASN product was not as economic to use as either SOA on readily leachable soils or urea on nonsulphur- limiting soils under wet Northland conditions. Keywords: ammonium sulphate nitrate, economic response, marine clay, nitrogen, sulphate of ammonia, urea, wet soils, Wharekohe silt loam
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(19 KB)The responses of two perennial ryegrass cultivars, Ellett and Grasslands Ruanui, to nitrogen fertiliser and irrigation, applied before and after flowering, were studied in a field experiment at the Dairying Research Corporation, Ruakura. The former was included as representative of the Mangere perennial ryegrass ecotype, and the latter as representative of older material. Data on herbage accumulation, tiller density and tiller weight were collected, before and after grazing by dairy cows, from September 1996. Nitrogen increased summer herbage accumulation and tiller density by 41% and 37%, respectively. Irrigation increased ryegrass yield by 21% in summer but effects on tiller density and weight were small and inconsistent. No significant effects of nitrogen fertiliser or irrigation treatments on herbage accumulation, tiller density, or tiller weight were observed in spring. Ellett swards produced 5390 kg DM/ha over the trial period, compared with 4450 kg DM/ ha for Grasslands Ruanui, although this difference was not statistically significant. However, Ellett had a larger mean tiller weight and a lower tiller density than Ruanui. The contrasting tiller size/ density characteristics of the two cultivars are quantified and discussed. Keywords: dairy cow grazing, Ellett ryegrass, Grasslands Ruanui ryegrass, herbage accumulation, irrigation, Lolium perenne,
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(53 KB)Since 1994 Ravensdown have carried out a series of pastoral trials in South Canterbury, aimed at looking at the relative effectiveness of different forms of nitrogen in the spring. These trials showed that in general those N products containing some nitrate-N (i.e., calcium ammonium nitrate – CAN, and ammonium sulphate nitrate – ASN) could be more effective than urea and ammonium sulphate when soil temperatures were low. However, responses were inconsistent because of spring climatic conditions. In 1994 and 1996 CAN produced the most dry matter but in 1995, responses to the form of N were less clear. Responses to nitrate-N were generally best when spring soil temperatures were 3–5°C at the time of application. The magnitude of N responses varied with the rate applied, and the type of pasture to which N was applied. Responses generally lasted the equivalent of two to three grazings. Keywords: ammonium-N, ammonium sulphate, ammonium sulphate nitrate, calcium ammonium nitrate, nitrate fertilisers, nitrate-N, urea
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(146 KB)Levels of treading damage were measured for a range of cattle feeding regimes and grazing managements which were compared during winter and spring. These paddock- and systems-based results provide a context within which component research on soil and plants can be interpreted. Soil surface damage was higher in farmlets with heavier cattle (390 kg vs. 200 kg steers) and on paddocks where feeding was restricted through the use of a slow rotation (100–120 days vs. 35–45 days). Where cattle grazed under wet conditions, with a pre- and post- grazing herbage mass of 2400 and 650 kg DM/ha respectively, damage levels reached 60-70% of the soil surface. Under these conditions, 300–350 kg DM/ha of initial forage on offer was pushed onto or into the surface soil; and pasture growth rates during early–mid spring would be reduced by 10 kg DM/ha/day. In practice the objective of grazing plans and management should be to minimise these negative impacts within the constraints of the required feeding regimes. Recommendations are made for the alignment of stock class and enterprise with land capabilities and the feed allocation processes of a winter rotation. Keywords: cattle grazing systems, forage supply treading damage
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(66 KB)In order to assist pastoral farmers determine whether investment in pasture development is worthwhile, a spreadsheet model was developed to analyse its effect on farm production and profit. The model incorporates a feed budget that accounts for the proportional impact of pasture development on the seasonality, quality and total supply of feed, and this is utilised to support additional livestock. The impact of pasture development on costs and revenue are accounted for in a yearly cash flow template because cash balances over the development period are a measure of feasibility. The effect of climatic conditions on pasture production, and hence livestock performance and sales, and of variation in future product prices were analysed for two case farms: one in New Zealand and the other in southern Brazil. The results, presented in terms of a probability distribution of the net present value (NPV) of the net profit after tax and before interest (NOPAT) for the pasture development programmes, provide a farmer with more insight into the physical and financial consequences of pasture development than an analysis based on current average costs and prices. Keywords: investment analysis, pasture development, profitability, risk, spreadsheet model
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(52 KB)Previous experiments with a sheep farm grazing model suggested a weakness in assumptions concerning pasture senescence and disappearance rates which was influencing the quantity and more importantly quality of pasture on offer and hence animal performance. Data from the Winchmore Research Station describing pasture masses and the amount of dead material in irrigated swards over several years have been used to derive joint estimates of growth and senescence rates and produced patterns similar to the few data available in the literature. Subjective estimates were made of likely differences in senescence between dryland and irrigated conditions and the model used to simulate the implications of these assumptions. Results demonstrate the sensitivity of animal performance to assumptions about the senescence and disappearance rates of pasture, particularly in the dryland situation where previously unrealistically high levels of performance were reduced closer to expected levels. This reinforces the desirability of collecting data on dead material in trials involving pasture measurements. Pasture production, percentage harvested and animal performance estimates from the model are presented. Keywords: Lolium perenne, pasture disappearance, pasture senescence, sheep grazing, simulation model, Trifolium repens
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(150 KB)Levels of treading damage were measured for a range of cattle feeding regimes and grazing managements which were compared during winter and spring. These paddock- and systems-based results provide a context within which component research on soil and plants can be interpreted. Soil surface damage was higher in farmlets with heavier cattle (390 kg vs. 200 kg steers) and on paddocks where feeding was restricted through the use of a slow rotation (100–120 days vs. 35–45 days). Where cattle grazed under wet conditions, with a pre- and post- grazing herbage mass of 2400 and 650 kg DM/ha respectively, damage levels reached 60-70% of the soil surface. Under these conditions, 300–350 kg DM/ha of initial forage on offer was pushed onto or into the surface soil; and pasture growth rates during early–mid spring would be reduced by 10 kg DM/ha/day. In practice the objective of grazing plans and management should be to minimise these negative impacts within the constraints of the required feeding regimes. Recommendations are made for the alignment of stock class and enterprise with land capabilities and the feed allocation processes of a winter rotation. Keywords: cattle grazing systems, forage supply treading damage
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(11205 KB)
Barkant turnips and Superchow sorghum were compared as summer–autumn crops for lactating cows, in a 2 × 3 factorial experiment fed at 3 levels (0, 4 and 8 kg DM/cow/day) to supplement pasture offered at a constant allowance of 25 kg DM/cow/ day. Sixty lactating twin cows were used in 2 experimental periods in January and March 1996. Pasture and crop intakes were estimated by the alkane, and pre- and post-grazing, techniques. Feeding either 4 or 8 kg DM/cow/day increased milksolids (MS) yield by 25% for turnips and 15% for sorghum compared with pasture alone. Turnips gave responses of 42.5 and 50 g MS/kg DM offered, at the lower allowance, in summer and autumn respectively; compared with 25 g MS/kg DM in both seasons for sorghum. Crop intakes were lower on sorghum than turnips and were only partially compensated for by increased pasture intakes on the former. For both crops, increasing allowance from 4 to 8 kg DM/cow/day did not increase daily MS yield. The cows grazing sorghum were 8 and 15 kg heavier than either the turnip or pasture-fed cows in summer and autumn respectively. Substitution rates for both crops were higher (0.72– 0.87) in summer than in autumn (0.35–0.45). This means that although both crops will have a “pasture sparing” effect in summer they will not contribute much to increased per cow intake. Keywords: alkanes, crop intake, dairy cows, milksolids, milk yield, pasture intake, sorghum, turnips Introductio
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(44 KB)Tall fescue (Festuca arundinacea Schreb.) is now well proven on New Zealand dairy farms as a pasture species capable of producing high levels of milk production. Compared with perennial ryegrass (Lolium perenne) it offers benefits of higher annual and summer growth, higher clover contents in pasture, higher green leaf to stem ratios in summer, reduced plant pulling, better animal health, grass grub (Costelytra zealandica) and Argentine stem weevil (Listronotus bonariensis) tolerance, tolerance of wet soils, and drought tolerance and growth. Tall fescue can be recommended for dairy farmers in areas where summer growth and quality of ryegrass is reduced by moisture stress or high temperatures, and for those willing to adjust their grazing and establishment practices to suit tall fescue. Keywords: dairy farms, Festuca arundinacea, tall fescue
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(48 KB)We purchased this property at Pokeno as a dry stock unit and converted it to dairying. Production in the first season (1989/90) was 16 500 kg milkfat (29 500 kg milksolids). Our farm is 60 effective ha (plus a large undeveloped area of the Mangatawhiri swamp), with a 20 ha runoff. The farm is 30 ha of stumpy peat soils, stopbanked but floodable from upstream ponding, and 30 ha of rolling Hamilton clay soils (75% mowable).
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(19 KB)
Pasture characteristics, soil moisture relations and water balance were measured in open pasture and in a mature poplar understorey, to assess how land conservation practices modify a pastoral system. Mature poplars changed the environment of the understorey pasture, with light intensity decreased from September to April, and the soil generally colder and drier in autumn and early winter. Soil moisture relations did not suggest strong competition for water between trees and pasture in spring. Pasture under the poplars accumulated 40% less herbage mass and was of lower feed quality than pasture in the open. The case study highlights the complexity of silvipastoral systems in hill country and the need for a more complete understanding of the interactions if the potential of a multipurpose tree and livestock farming systems is to be realised. Keywords: conservation, pasture characteristics, poplar, Populus deltoides, sapflow, soil moisture, silvipasture, trees, water balance
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(61 KB)Information on tree growth rates, economic returns and the effects of trees on pasture for radiata pine, Australian blackwood and Eucalyptus fastigata were analysed to assess the economic returns of using these tree species within a hill country farming operation. Under the assumptions made, all three species options were more profitable in the long run than sheep and beef farming. Radiata pine produced the greatest return, large increases in log prices or yields of other tree species being required to give equal profit. The results of the analysis and market information emphasise the importance of good site selection and silviculture in the production of high quality timber. For some species these requirements may not fit on-farm production systems or be economically attractive. Keywords: Acacia melanoxylon, agroforestry, Eucalyptus fastigata, hill country farming, Pinus radiata
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(42 KB)An estimated 3.7 million ha or 33% of the North Island requires the application of significant soil conservation measures to be able to physically sustain pastoral enterprises. Traditionally, erosion control measures on hill farmland have centred on the planting of hardwood trees, such as poplars and willows, at wide spacings. Research and experience has confirmed that where hardwood trees are adequately planted and tended, they significantly reduce the magnitude of soil erosion and maintain soil stability. However, the effects that such erosion-control plantings have on pasture and animal production owing to changes in the farm microclimate, soil and water resources remains relatively unresearched in New Zealand. Keywords: hardwood trees, physical sustainability, silvipastoral systems, soil conservation
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(46 KB)
A study was undertaken to identify the relationships between farmers’ values and their farming goals. Fifty goals were first identified from interviews with 20 farmers in the Waikite Valley. In a further survey of 1100 farmers in Hawke’s Bay, King Country and Taranaki, respondents were asked to score the importance of each of the goals. The survey had 680 responses. Cluster analyses of the scores from the survey were used as the basis for developing 10 goal categories. The most important category of goals for 43% of the farmers was that related to maximising farm production and profitability. These goals could be associated with people who put a priority upon values which emphasised individual success. The environmental goal category was prioritised by 7% of farmers, with values emphasising the welfare of others and the management of natural resources. The implications of this study for consultancy strategies are that although most farmers ranked their production goals very highly, they also wanted to realise a whole range of other goals (often including the environment), all of which needed to be addressed. Policy agencies associated with environmental management to implement the Resource Management Act (1991) should develop strategies of working with farmers that account for the multiple goal structure of farming styles. This can be done by providing farmers with management options that can be used to satisfy a number of farming goals. The availability of such management options is likely to encourage greater levels of voluntary change. Keywords: farming styles, goals, planning, values
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(54 KB)Farmers’ conferences have been a key technology transfer mechanism for agricultural research over many years. However, farmer support for these events has been declining. As part of a review of the Ruakura Dairy Farmers’ Conference, a study was conducted to determine the information needs of dairy farmers, and establish the best methods of communicating research findings to farmers at conferences. The four predominant information needs of dairy farmers pertained to increasing the efficiency of labour use, increasing farm profitability, reducing the impact of farm practice on the environment and animal welfare, and increasing business management skills. While many of these broad categories fall outside the traditional sphere of agricultural research, researchers must relate their findings to these information needs if they are to communicate research effectively. Conference organisers must provide farmer audiences with a programme which is directly related to their goals. To improve communication there should be a move away from lecture-based presentations to interactive workshop and seminar sessions. Not only does this better suit the learning style of many farmers, but it provides researchers with an opportunity to receive feedback on their ideas from those who will apply the knowledge. Agricultural scientists may need to change the emphasis of their research and assess their methods of technology transfer if they are to continue to make a major contribution to the grass roots level of the dairy industry. Keywords: conference, dairy industry, information needs, technology transfer
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(44 KB)This paper reports the results of a dairying systems study at No. 4 Dairy, Massey University, investigating whether the benefits of contrasting spring grazing managements previously measured in small-scale experiments could be measured within the management constraints of a selfcontained farm production system. Management contrasts were early control (EC), in which pastures were closely controlled throughout spring and summer, with average pasture cover kept at approximately 2000 kg DM/ha, and late control (LC), in which average pasture cover was increased to 2700 kg DM/ha, allowing some reproductive growth through October and November before returning average pasture cover to 2000 kg DM/ha in December. Average pasture cover and pre- and post-grazing cover differences between treatments were achieved over late spring in all three years. However, average pasture cover during summer did not differ between treatments. Milksolids (MS) production per cow during the spring phase was higher for the LC treatment than for EC, but the differences disappeared over the December control phase and overall differences were small and inconsistent. The use of mechanical topping in December 1995/96 reduced the penalty to LC MS production experienced in previous years. Late control spring grazing management did not significantly increase pasture or MS production within the confines of a closed production system, contrary to the results of previous small-plot and paddock-scale experiments. Keywords: dairy cow, dairy systems, Lolium perenne, milksolids production, pasture production, spring grazing management, Trifolium repens
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(69 KB)Agri-environmental indicators developed in New Zealand to date have focused more on environmental and biophysical indicators than on social and financial measures. However, the latter are increasingly seen as pre-requisites to achieving long-term financial and social viability in agriculture. At present environmental costs are internalised in the financial performance of farm businesses because environmental protection in agriculture is funded almost entirely by farmers. This paper presents a preliminary examination of the perceptions of farmers on the relationship between farm financial resources and the environmental effects of farming. It aims to identify pragmatic and reliable financial indicators of sustainable agriculture at both the farm and the regional or national level. The paper will introduce a range of indicators used to measure the financial health of a business and will evaluate them for their ability to measure the economic sustainability of farm businesses over time. Farmer perceptions of the existence of links between the financial and environmental indicators will be explored through analysis of interview responses. Keywords: financial health, sustainability indicators, environmental indicators, financial indicators
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(26 KB)The performance of winter milk production systems, represented by between 7 and 17 New Zealand Dairy Group suppliers in the South Auckland area, has been assessed for seven consecutive years. The monitoring programme has enabled comparison of winter milk systems with typical seasonal supply systems, and identification of management issues facing winter milkers. In 1995/ 96 the monitored farms had contract volumes ranging between 7 and 32 litres/ha (average 21 litres/ha). This reflected the total situation for all the NZDG winter milkers. Total annual production is also critical for profitability, and ranged between 684 and 1107 kg milksolids (MS)/ha in the year ending 31 August 1996 (mean 920 ± 144 kg MS/ha). The main requirements for successful winter milk production include planning and acting early for winter, in particular by: 1. early use of supplements in the autumn, including hay, silage and urea; 2. appropriate drying off of cows; and 3. grazing drystock off the home farm, so it can be effectively used as a milking platform. Keywords: dairying, farm monitoring, South Auckland, winter milk
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(38 KB)Three levels of planning can be distinguished in grassland farming: strategic, tactical and operational. The purpose of strategic planning is to achieve a sustainable long-term fit of the farm business with its physical, social and financial environment. In pastoral farming, this essentially means developing plans that maximise and best match pasture growth with animal demand, while generating sufficient income to maintain or enhance farm resources and improvements, and attain personal and financial goals. Strategic plans relate to the whole farm business and are focused on the means to achieve future needs. They should be routinely (at least annually) reviewed and monitored for effectiveness through key performance indicators (e.g., Economic Farm Surplus) that enable progress toward goals to be measured in a timely and cost-effective manner. Failure to link strategy with control is likely to result in unfulfilled plans. Keywords: management, performance
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(64 KB)
Aries HD perennial ryegrass (Lolium perenne L.) has been selected for increased digestibility in summer and early autumn. It is claimed to be the first commercial perennial ryegrass selected specifically for improved digestibility. The relative performance of weaned Romney lambs over summer was compared using Yatsyn 1 perennial ryegrass as a control cultivar. There were 3 replicates of each cultivar of 0.33 ha initially stocked with 8 lambs/plot (24 lambs/ha). Swards were continuously stocked with lambs with a variable stocking rate to maintain a mean sward surface height of 6 cm. Lambs grazing Aries HD plots consistently achieved higher liveweight gains over the experiment. Liveweight gain was higher on Aries HD than Yatsyn 1 during summer dry conditions 24/1/96 to 4/3/96 (50 vs. 31 ± 7.8 g/ day, P<0.035) and overall (104 vs. 84 ± 4.6 g/day, P<0.103). During summer on average 15% of lambs grazing Aries HD pasture were severely affected by perennial ryegrass staggers compared with 29% of lambs on Yatsyn 1 pastures (P<0.027). Information on pasture quality, alkaloid concentrations, and herbage intake is presented and discussed in relation to the differences in animal performance. Keywords: alkaloids, animal evaluation, Aries HD perennial ryegrass, digestibility, lamb performance, Lolium perenne, ryegrass–endophyte association, ryegrass staggers
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(47 KB)Results are presented for 16 National Forage Variety Trials of annual and short-term hybrid ryegrass cultivars conducted in Waikato, Taranaki, Manawatu, Canterbury and Southland. In all, 30 cultivars (17 named, 13 experimental) were included. Cultivar effects were significant in all seasons, and for the annual totals. Cultivar differences were greatest in summer. Spring production accounted for over 40% of annual totals and summer production less than 20%, but it was summer production that was more closely correlated with the individual cultivar annual total. Over all trials and cultivars, regrowth in the second autumn accounted for 11% of the total for 12 months beginning in the winter following sowing. Comparing North Island sites with Canterbury sites, there was some indication of cultivar × region interaction, particularly in summer. Patterns of interaction of cultivars with trials were examined, and indicated that some cultivars can be grouped as having similar responses. Repeated trials at the same site were sometimes but not always consistent in ranking cultivars. The results indicate that some cultivars do perform consistently better than others, for particular seasons or for annual totals, so that the trials are a reliable indicator of which new experimental cultivars should be released to the market. The results also indicate that several trials are necessary to determine the merit of a wellperforming cultivar. The error associated with the mean of cultivars present in only one or two trials is high (standard deviation approaching 20% of the mean in some seasons). This may, however, be sufficient to eliminate poorer experimental lines from further consideration. Keywords: Italian ryegrass, hybrid ryegrass, cultivars, Lolium × boucheanum, Lolium multiflorum, pasture agronomy
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(53 KB)Caucasian clover (CC) and white clover (WC) pastures were established on a Bay of Plenty dairy farm in September 1994 and undersown with ryegrass (RG) in July 1995. Yields of mown RG– CC plots surpassed those of RG–WC plots from December to April in the second year after establishment (1995/96), producing 1362 kg (26%) extra DM/ha during this period. In 1996/97 yields of RG–CC plots surpassed those of RG–WC from October to April, producing 1531 kg (43%) extra DM/ha in December–April. In grazed RG–CC plots during December-May 1996/97, RG yields were slightly reduced (371 kg/ha, –12%) in comparison with RG–WC plots, and extra production resulted from greatly increased total legume yield (2155 kg/ha, 187%). Pasture legume content during summer–autumn averaged 24% for RG–WC and 54% for the RG–CC pastures. The superior performance of CC over WC appeared to relate to its protected underground growing points, and taproot retention, facilitating better pasture cover during summer, and greater tolerance of pests including grass grub and clover cyst nematode. Caucasian clover shows promise as a perennial legume which may offer improved availability of high quality forage at a time of year when clover growth is often insufficient for good animal performance. Caucasian clover clearly has potential in northern as well as southern regions of New Zealand. Keywords: dairy pasture, Lolium perenne, northern New Zealand, pasture pests, Trifolium ambiguum, Trifolium repens
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(57 KB)A study was undertaken to determine the reason for the differences in the estimation of pasture mass between dairying research centres in New Zealand and to define a common system of estimation that would overcome these differences and be able to describe the pasture situation on commercial dairy farms in different parts of New Zealand. Differences in the visual estimation of pasture between a standard observer and a local observer at the different dairying research centres in the order of 900 kg DM/ha were identified. This was attributed to a lack of regular visual calibration of persons who regularly assessed pasture, as differences between centres in the actual harvested DM yields of the visually assessed plots varied less (200–400 kg DM/ha). To achieve uniformity it is recommended that all centres measure total herbage mass (the amount of herbage above ground level) to regularly calibrate pasture assessment in dairy grazing management studies and on dairy farms. A reasonably consistent estimation of average farm cover, the ranking of paddocks (r2 > 0.9) for the purposes of determining grazing order and the estimation of pre- and post-grazing herbage mass was achieved using the rising plate meter and L’Huillier & Thomson’s standard set of calibration equations published in 1988. With these recommendations, estimation of pasture will be more uniform. Standard calibration of the plate meter for the determination of rate of DM disappearance (pre-post grazing) achieved less consistency. Keywords: herbage mass, pasture assessment, pasture height, rising plate meter, visual pasture estimation
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(44 KB)Ryegrass contamination of endophyte-free ryegrass (Lolium perenne L.) pastures, established by autumn spray–drilling of existing endophyteinfected pasture, was studied over one year at the Dairying Research Corporation, Hamilton. Main plots were sprayed with glyphosate at 1.44 kg a.i./ ha (4 l/ha of Roundup G2) in mid-March 1996 (S), or mid March and again in mid April (D). White clover (Trifolium repens L.) was removed from half the area of each main plot using herbicide and the remainder was drilled with white clover. All plots were direct drilled with endophyte-free perennial ryegrass in late April. Plots were rotationally grazed by dairy cows. Volunteer perennial ryegrass seedlings that germinated from seed in dung pats, on the soil surface (reseeding) and after recovery from the seed-bank, contained 40, 66 and 69% endophyte, respectively. The largest inputs of volunteers came from dung and reseeding. The average dung pat covered 0.08 m2 and supported 3 volunteer ryegrass seedlings (range 0– 14). After the first spraying 0.87 ryegrass clumps/ m2 were surviving, and 0.13/m2 survived both herbicide applications; half were infected with endophyte. After one year, contamination of S was 2.5 times higher than D plots (18 vs 7% of plants endophyte infected), showing that double spraying in autumn was effective at reducing contamination to a low level. Keywords: dairy pastures, dung, endophyte, Lolium perenne, reseeding, seed-bank, seed transfer, volunteer ryegrass
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