The use of fodder beet as the primary diet for finishing beef cattle is a recent New Zealand innovation. A system using ad libitum grazed fodder beet through autumn and winter to finish spring-born steers between 12 and 18 months old was developed. Fodder beet is a high energy yet comparatively low protein content feed, and the fodder beet system requires high liveweight gains on the crop and an early slaughter age for cost effective production. Lower liveweight weaners have a greater protein requirement for optimal weight gain, and the threshold entry liveweight for satisfactory performance in this feeding system was not yet established. The objective of this study was to quantify the effect of the entry liveweight of weaners on liveweight gain in the fodder beet feeding system. A group of 392 rising 1-year-old beef cattle fed using this system were divided at entry into three groups on unfasted liveweight (kg): A, 290–370; B, 240–260; and the remaining animals. The heaviest (group A: steer n=67, 316 ±2.7 kg; heifer n=45, 312 ±2.5 kg) and lightest (group B: steer n=77, 249 ±0.7 kg; heifer n=19, 251 ±1.0 kg) groups were then treated identically on ad libitum fodder beet to compare liveweight gain across 130 days on crop. The mean liveweight daily gain (kg/ day) for group A was significantly greater than group B, and greater for the steers compared to heifers in group A (0.98 and 0.85), but not in group B (0.82 and 0.81). Mean liveweight gain as a proportion of entry liveweight was greater in group B, and greater in steers. Both mean daily liveweight gain and mean liveweight gain as a proportion of entry liveweight were positively correlated with entry liveweight, but the R2 of both was low (0.14 and 0.05, respectively). Mean daily liveweight gain values of this magnitude are greater than those previously reported for alternative winter crops, and satisfactory for finishing beef cattle in this system. This study suggests the use of beef cattle above 240 kg liveweight as weaners in this fodder beet feeding system, both steers and heifers, is satisfactory for achieving acceptable slaughter liveweight before 18 months old. Keywords: beef production, fodder beet, finishing cattle, ad libitum fodder beet intakes.
A large number of white clover cultivars bred both in New Zealand and overseas are available for use by New Zealand pastoral farmers. Unfortunately, there is little published data on the merits of many of these cultivars under grazing in New Zealand. Data from a series of trials established in the Manawatu between 1996 and 2005 containing a range of cultivars from Europe, the Mediterranean, North and South America and New Zealand were used in a meta-analysis to assess the general adaptive yield and persistence potential of these contrasting cultivar types. All trials were maintained over 2 to 4 years, and revealed significant cultivar effects. Overall, New Zealand bred cultivars showed better adaptation than overseas cultivars. However, overseas cultivars containing Mediterranean germplasm, particularly from southern France, Italy and Syria exhibited beneficial features in the trials, and many recently bred New Zealand cultivars contain germplasm from these origins. In addition to using the appropriate parent germplasm when developing cultivars, it is equally important to evaluate and select under local conditions, in competition with grass, under grazing, over multiple environments and years. New Zealand farmers may benefit from an industrywide benchmarking system for white clover cultivars, possibly by incorporation into the DairyNZ Forage Value Index. Keywords: white clover, cultivars, germplasm, local, overseas, adaptation
Field trials under grazing on two contrasting dairy farms in mid-Canterbury (Site C) on a stony silt loam under irrigation, and in rain-fed central Waikato (Site W) on a volcanic ash-derived soil, compared standard granular urea (4–5 mm diameter granules) with ONEsystem®. This uses prilled urea (0.8–2.8 mm diameter prills), passed through a fine water spray (50 litres/ha) that contains the urease inhibitor nbpt (2 gm nbpt/kg N) during application. A nil N control and three rates of each fertiliser were applied to 12 × 25 m plots on four occasions after rotational grazing during spring/early summer 2014. ONEsystem® resulted in extra dry matter (EDM) to N applied compared with granular urea at Site C. At Site W, the initial advantage to ONEsystem® in Period 1 (early spring) was not maintained. To produce EDM of 1250 (±750) kg/ha required 120 and 126 kg N/ha as granular urea at Sites C and W, respectively (giving EDM factors of 10.4 and 9.9 (± 2) kgDM/ kgN applied respectively). This compares with 50 and 74 kg N/ha required with ONEsystem® for higher EDM factors of 24 and 17 (± 5) kg DM/ kg N. Pasture N concentrations were higher at Site C following ONEsystem® application, and total N uptake was increased 3-fold compared to granular urea. At Site W, increases in EDM with ONEsystem® only occurred in the first period. The results of this study have implications for both the economic and environmental efficiency of fertiliser urea use on grazed pastures. Keywords: ONEsystem®, prilled urea, nbpt, granular urea, N efficiency, pasture, N uptake
Morton et al. (2014) presented the results from two rates of potassium (K) pasture trials conducted on Pumice soils which commenced in spring 2009 and ran for 3 years. They reached a number of conclusions with respect to the management of potassium requirements on such soils, based on the soil Quick Test K (QTK) samples (0–75 mm) collected in spring and suggested that the results from these two sites were unique. While noting that soil samples were collected in the autumn, they did not include these data in their anaylsis and discussion of the results. This communication discusses the implications of this omission. Keywords: potassium, pasture, pumice, soil tests
On New Zealand dairy farms the level of pasture renewal has been estimated at 6% and 8%, with one analysis suggesting greater levels would benefit the economy. There is little research on how farmers set a renewal level, but we suggest five main drivers: crop requirement, historical, an event response, development and cost/benefit driven. This paper presents a case study using a cost/benefit approach to pasture renewal for Willsden dairy farm in Canterbury, which has renewed 28% and 38% of the property in the last 2 seasons. On this farm spray-drilling Italian ryegrass has shown an estimated 1.7 t DM/ha/year extra yield in the season of sowing, with a net value of $1090/ha, suggesting a payback period of around 5 months and a 198% return within the season of sowing. This case study shows there is a significant opportunity for dairy farmers to profit from better use of weekly pasture cover information to plan pasture renewal, to better assess the success of any renewal, and for pasture management software developers to provide automated analysis options to support a cost/benefit pasture renewal strategy. Keywords: pasture renewal, spray-drill, spraycultivate, perennial ryegrass, Italian ryegrass
Many farmers are sowing mixed swards containing chicory (Cichorium intybus), plantain (Plantago lanceolata), red clover (Trifolium pratense) and white clover (T. repens) (hereafter termed herb and clover mix). This herb and clover mix has comparable annual dry matter (DM) production to perennial ryegrass white clover pasture (rye/wc), however, it has a different pattern of growth, producing more DM during summer and autumn. The herb and clover mix also has a higher nutritive value and is able to support greater rates of animal production, especially over summer, than rye/ wc in both sheep and cattle. The herb and clover mix is most suited to a rotational grazing interval of 3–4 weeks to an 8 cm residual height, with no winter grazing. When managed appropriately the herb and clover mix is able to persist for at least 2 years and up to 5 years under both sheep and cattle grazing. Keywords: Cichorium intybus, Plantago lanceolata, Trifolium pratense, Trifolium repens, legume, perennial, nutritive value.
Commercial units of Active Optical Sensor (AOS) systems are designed for sensing arable crops to estimate the required amount of nitrogen fertiliser and are well established in intensive arable cropping systems in Europe. A research version AOS (RU-AOS) of a commercial system was tested as a potential canopy sensor for New Zealand dairy pastures. To study the applicability of this sensor a sensitivity experiment was conducted. Additionally, a plot experiment investigated the relationship between the spectrometer and biomass attributes on ryegrass and white clover canopies fertilised with five different nitrogen amounts. The pasture plots were sensed with the RU-AOS and results compared with measured biomass dry matter and nitrogen amount. For some events a strong linear relationship between dry matter (DM) and the water index (WI) was evident (i.e. r2 = 0.80) as well as between nitrogen (N) amount and simple ratio (SR) (i.e. r2 = 0.89). The results suggest there is potential for this sensor to estimate New Zealand dairy pasture attributes. This could be used to develop a pasture system similar to commercial arable cropping nitrogen sensor AOSs. Keywords: Active Optical Sensor; pasture; nitrogen
An on-farm demonstration compared the use of perennial ryegrass based pasture or lucerne as the forage source for in-lamb ewe lambs from 2 weeks prior to lambing until weaning in the Te Anau basin. This demonstration, over 2 years, used 632 and 506 in-lamb ewe lambs in 2013 and 2014 respectively with approximately 50% being single-bearing and 50% twin-bearing in both years. Pasture and lucerne were set stocked until docking at approximately 33 days of age and then rotationally grazed thereafter until weaning at approximately 110 days of age. Ewe liveweights and body condition scores tended to be higher when grazed on lucerne during spring and all ewes were at or near two-tooth mating weights at weaning (67 kg). Lamb liveweights at 110 days of age were similar from the pasture and lucerne (33.4 kg). Lamb losses were greater on lucerne (37%) than pasture (28%) in both years, and led to a significantly lower lambing percentage on lucerne. Stocking rate chosen based on previous pasture growth records and potential lucerne yield was greater on lucerne (11.7 ewes/ha) than that on pasture (9.4 ewes/ha). The combined liveweight gain of ewes and their lambs per hectare was significantly greater from lucerne (492 kg/ha) than pasture (398 kg/ ha). Scanning data from the second mating was 201% and 189% in ewes that had grazed on lucerne or pasture during the previous lactation respectively, while ewes weighed 67.7 and 65.1 kg at mating respectively. Lucerne can be used as a forage option to increase the performance of bred ewe lambs but the grazing of young lush growth should be avoided to reduce potential animal health issues. Keywords: body condition score, ewe lambs, lamb liveweight gain, lamb survival, reproduction
A demonstration wetland was constructed with community support in what was a “wet” 0.75 ha of a Wairarapa dairy farm. This has reduced the level of nitrate-nitrogen leaving the farm, and has also added biodiversity to the farm and the region. Comparison of nitrate-N levels of water flowing in and out of the wetland over three months show this water quality benefit may reduce farm N loss from 14 down to 13 kg N/ha/yr, which equates to an ongoing reduction of around 7% for a one-off investment of at least $55l000. However, other contaminants such as dissolved reactive phosphate may not necessarily be reduced, while counts of Escherichia coli increased in wetland outflow. This project required a range of skills unlikely to be available to an individual farmer without wider community support but now that the wetland is established it will demonstrate what is possible when more complex solutions are implemented for nutrient loss mitigation. Keywords: dairy farm, constructed wetland, denitrification, nitrate-N, water quality, biodiversity
Grazing a winter forage crop can result in a substantial increase in soil nitrogen (N) from urine deposition, with a significant proportion leached below 30 cm during winter. If a follow-on crop can be used to recover this soil N before the following drainage season, N leaching risk could be reduced. We tested if faster growing, or deeper-rooted, spring-sown crops would be more effective at recovering winter-deposited N than ryegrass based pasture. Urea-N (800 kg N/ha) was applied in June to simulate a dairy cow urine patch and was subsequently leached down the soil profile. In the spring, the plots were sown with ryegrass, chicory and clover, or barley and harvested manually. The following autumn, the amount of N in the 60–90 cm depth (70 kg N/ha) was significantly less (P<0.05) under chicory and clover than under either barley (104 kg N/ha) or ryegrass (107 kg N/ha), suggesting that chicory was able to access the deep N pool. These data, and earlier measurements, provide evidence that chicory is a viable strategy for N recovery after winter grazing. Keywords: Nitrogen, urine, forage crop, leaching, chicory
Clarence and Elise Stolte farm the family Masterton property as 50:50 sharemilkers. They have made the 285 ha dairy farming business resilient to environmental and milk price volatility by remaining focussed on sustainable results and not productivity. Evidenced through the Dairy Systems Monitoring (DSM) and the Dairy Farm Business of the Year competition they stand in the top 10% of elite groups for financial results in both high payout in a high pasture yield season, and then in the following low payout, low pasture yield season. Being able to demonstrate consistent results comes from a deliberately well considered farm policy, skilled on-farm management, maximising home grown feed yields and strong discipline around the farm budget.
Effects of tall fescue cultivar (‘Advance’ and ‘Flecha’) and clover species (white and subterranean (sub) clovers) combinations on pasture dry matter (DM) and sheep production were assessed in years four (2011/12), five (2012/13) and six (2013/14) after establishment in dryland, Canterbury. ‘Advance’ pastures yielded less total herbage than ‘Flecha’ pastures (13.9 cf. 16.5 t DM/ha) but more fescue (8.6 cf. 5.9 t DM/ha) and 2.1 t DM/ha clover in year four, 13.5 t DM/ha total herbage with more fescue (8.0 cf. 4.1 t DM/ha) and 1.9 t DM/ha clover in year five, and 11.7 t DM/ha total herbage, 5.4 t DM/ha fescue and 0.8 t DM/ha clover in year six. Sub clover pastures yielded more total, fescue and clover herbage (16.9, 8.8 and 3.2 t DM/ha) than white clover pastures (13.5, 5.7 and 1.0 t DM/ha) in year four, more fescue in year five (7.2 cf. 4.9 t DM/ha), and more clover in year six (1.2 cf. 0.3 t DM/ha). Sheep liveweight gain was greater for sub than white clover pastures in year four (939 cf. 431 kg/ha) and five (697 cf. 481 kg/ha) and 689 kg/ha in year six. Therefore, sub clover and ‘Advance’ were generally more productive than white clover and ‘Flecha’, but both fescues showed similar persistence after 6 years. Keywords: cultivar, Festuca arundinacea, grass-clover mixtures, liveweight gain, Trifolium subterraneum, Trifolium repens
Monocultures of arrowleaf (Trifolium vesiculosum), balansa (T. michelianum), gland (T. glanduliferum) and Persian (T. resupinatum) clovers were sown on four dates in autumn and winter 2010. Dry matter (DM) accumulation was dependent on the duration of crop growth which was influenced by the time of sowing. Autumn sown crops which flowered latest had a longer duration of vegetative growth and consequently produced the highest dry matter yields. In the establishment year, autumn sown crops produced up to 17.5 t DM/ha for balansa, 12.5 t DM/ha for Persian, 11.0 t DM/ha for gland and 9.4 t DM/ha for arrowleaf at physiological maturity (P<0.05). Crops that were sown in winter produced the lowest yield, because reproductive development commenced earlier and therefore they matured earlier. ‘Bolta’ balansa clover had the highest radiation use efficiency of 2.1 g DM/MJ photosynthetically active radiation (PAR) absorbed followed by gland (1.6 g DM/MJ PAR), arrowleaf and Persian (1.3 g DM/MJ PAR) clovers. In the second year, regenerated dry matter production at full flower was up to 11.6 t/ha in balansa, 8.3 t/ha in Persian, 2.9 t/ha in gland but only 0.5 t/ha in arrowleaf clover (P<0.05). Thus, over the two years ‘Bolta’ balansa and ‘Mihi’ Persian clovers were the highest yielding and easiest to regenerate from seed in monocultures. ‘Cefalu’ arrowleaf failed to regenerate in the second year due to low population of seedling emergence. ‘Prima’ gland clover was low yielding because it flowered and matured without fully utilising the growing season. Keywords: biomass, canopy expansion, day length, light interception, thermal time.
Four annual clovers (Arrowleaf (Trifolium versiculosum), balansa (T. michelianum), Persian (T. resupinatum) and gland (T. glanduliferum)) were sown on five East Coast dryland farms and one moist Taranaki site. Hardseededness was measured at all sites and seed production and hardseededness was measured at three sites following different closing dates. There were no differences in seed size for any species between sites or closing dates. High levels of seed (500–700 kg/ha) were set by balansa and arrowleaf clovers after an early closing date (early September). Flowering and seed production decreased with later closings. Gland clover was the earliest to flower and with Persian clover was very susceptible to early grazing. Gland clover produced virtually no seed as flowers had already been grazed prior to the first closing. Arrowleaf clover produced very high levels (>92%) of hard seed and Persian very low levels (<1%). Lack of hardseededness led to Persian clover seed being lost to false strikes, with most seed germinating in the seed head following January and February rains. Balansa, when carefully managed, appears to be the only annual clover which regenerates in its second season in East Coast dryland conditions. Keywords: arrowleaf clover, Persian clover, balansa clover, gland clover, hard seed, seed production.
Changes in voluntary feed intake (VFI) and average daily gain (ADG) of 10- to 12-month-old male red deer (Cervus elaphus) in response to a range of pasture morphological development stages of perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) pasture in spring were investigated. An intake study in November 2000 tested responses to pastures spelled for 6, 8 or 10 weeks in a combined indoor/outdoor comparison over two weeks. This was followed by a 5 week grazing study which compared 3, 5 or 7 week spelling periods during November and December in 2001. Pasture spelled for 6, 8 or 10 weeks had acid detergent fibre concentrations of 216, 229 and 252 g/kg DM (P<0.001) and seed head proportions of 145, 364 and 539 g/kg DM (P<0.001) respectively. As spelling interval increased from 6 to 10 weeks ADG declined (P=0.003) from 394 g/day to 361 g/day and 221 g/day. VFI also declined from 2.40, to 2.23 and 1.64 kg DM/day (P=0.016), and digestibility declined from 786 to 764 and 734 g/kg DM (P=0.002). The grazing study comparing 3, 5 or 7 week spelling provided a different response to spelling interval as seed head production was similar regardless of spelling interval. During the course of the grazing study voluntary feed intake increased from 1.93 kg DM/day to 2.69 kg DM/day (P=0.004), while the digestibility of the forage declined from 719 to 687 g/kg DM (P=0.013). The energy lost during digestion increased by 4.9% for every 10% increase in seed head offered (P=0.011). The coefficient of conversion of digestible energy to metabolisable energy declined from 0.86 to 0.56 as the diet offered increased from 0% to 60% seed head. Keywords: feed intake, forage quality, growth, digestible energy, red deer, spring.
Developing a genomic selection (GS) strategy for ryegrass requires field data for training GS models and to gain insight into how ryegrass agronomic performance varies, within and among populations and across locations. Families from five perennial ryegrass breeding populations are being evaluated in eight trials in Northland, Waikato, Hawke’s Bay, Manawatu and Canterbury to establish a data set for development of a genomic selection model. Statistically robust variances are evident among families within populations, both for visual scoring of herbage bulk and dry matter measurements. Multi-trial analysis of data showed significant (P<0.001) differences among families, robust across trials, even though interaction with trial was also significant in some seasons. Patterns are also evident comparing trials, with relative performance of families being similar for some pairs of trials, but radically different for others. Evidence for specific response of families to severe summer management was not conclusive. Keywords: genomic selection, ryegrass, genotype by environment interaction
Development of mānuka (Leptospermum scoparium) and gorse (Ulex europaeus) is a widespread problem on pastoral hill country and is associated with reduced fertiliser inputs and grazing pressures. Using mānuka as a source for specialty products offers a potentially new, profitable enterprise alongside livestock and forestry. However, there is a lack of quantitative information on the optimum soil nutrient status and associated fertiliser programme to encourage presence and growth of this species. In a survey across 324 grazed sites, mānuka had greatest presence on steep slopes (>25o) and soils with Olsen P <10 μg/ml. Mānuka presence was three times greater on steep than medium slopes (13– 25o) and 12 times greater than on low slopes (<13o). Annual fertiliser inputs did not appear to change this outcome provided Olsen P remained low. Mānuka was virtually absent where Olsen P approached 50 μg/ml. At other grazed sites, mānuka and gorse were most likely to occur where Olsen P was <15 μg/ml. This study provided insights to underpin a set of nutrient guidelines for mānuka under grazing conditions to maximise its establishment and growth. It remains to be determined what the optimum Olsen P level is for this plant when managed in regimes without grazing and treading pressure. Keywords: mānuka, gorse, soil fertility, hill country
My wife Jo and I are shareholding managers of Patitapu Station at Alfredton in the North Wairarapa. It is a family business consisting of 2550 ha (1760 ha effective) predominately hill country, approximately half way between the Tararua ranges and Castlepoint. It runs 17 500 s.u, 75% sheep, 25 % cattle, predominantly breeding with some finishing. It is highly variable in terms of contour, aspect, soil type, altitude and climate. Patitapu was purchased and developed by my father from 2000. This development has covered all aspects of the farm. With Wairere as an example on our southern boundary, the backbone of the development plan was traditional with the tried and true recipe of fencing/water, fertiliser/lime and hoof and tooth pasture development. A 200 ha block was roller crushed and developed out of gorse and scrub. All of the infrastructure has been upgraded, flock genetics changed and 120 ha of cultivatable ground brought in.
White clover (Trifolium repens L.) continues to play a pivotal role in the Australasian pastoral industry, despite increased use of nitrogen fertiliser on farms. Improved white clovers for dairy farming must be well adapted to the farm systems they are intended for, including increased rates of fertiliser nitrogen, higher stocking rates and access to irrigation. The breeding objective was to develop a white clover cultivar in evaluation systems that simulate modern farming practices, and test that cultivar in both New Zealand and Australia for adaptation and agronomic merit. This included breeding and early generation evaluation at research farms in the Manawatu and Waikato, with subsequent evaluations in these locations and farms in Southland and Victoria, Australia. This resulted in ‘Grasslands Legacy’, a new large leaved white clover cultivar bred for New Zealand and eastern temperate Australian pastures, which has shown significant (P<0.05) improvement on New Zealand cultivars including ‘Kopu II’ and ‘Kotare’. ‘Grasslands Legacy’ offers good utility for modern intensive pastoral systems, particularly through yield, persistence, and improved adaptation to abiotic stress. Keywords Breeding, abiotic stress, Australasia, genotype × environment, Trifolium repens
Around 70 percent (guesstimate) of New Zealand’s sheep and beef population is farmed on uncultivatable hill country. There are large areas where individual farms have less than ten percent available for cultivation. Wairere is such a property. Originally the southern end of the “seventy mile bush”, the soils are poor, derived from sandstone and clay, with pHs of 4.9–5.2 and phosphorus (P) levels of 1–2. Following initial land clearing there were several rounds of reversion to Manuka until the mid 1960s when my father John embarked on a programme which included large inputs of lime, at 5 t/hectare, super at 1 t/hectare, and DAP at 100 kg/hectare, all flown on in the first 28 months. This programme took from 1965 to 1982. I personally spent nine months cutting scrub—more recently I have been a shareholder in a manuka honey company planting scrub, how things go round! This programme was accompanied by subdivision and provision of stock water by the construction of dams. There were invasions of porina and manuka beetle following development, and porina control is still required on a regular basis. Wairere has run performance recorded sheep since 1967, based on a registered Romney stud started by my grandfather in 1929. We winter around 9500 sheep and 340 cattle on 1070 effective hectares. The 5300 ewes wean 145 percent average; the 2000 ewe hoggets (all in lamb) wean around 1700 lambs. All hoggets have been mated for the past 50 years; the 1800–2000 ram hoggets are culled lightly in late winter, and taken through to private sale in November; the 300 cows (replacements bought in) calve from mid October, with most wearers sold in April.
Plant breeders aim to develop cultivars of perennial ryegrass Lolium perenne L., (PRG) that better support New Zealand farmers through improved genetic potential for key traits such as seasonal dry matter yield. Hybrid vigour (heterosis) may be one way plant breeders can increase dry matter yields, and potentially lift the long term rate of genetic gain. We report evaluation of PRG full-sibling progeny for heterosis expressed under grazing. Parents were randomly sampled from sixteen cultivars, and for each cultivar combination within mid-season and late season classes, six pair crosses were made. In 2013, replicated single row trials of parent cultivar samples and progeny were sown at two sites near Palmerston North. For 2 years, prior to each grazing, growth score (GS) data were recorded to estimate dry matter yield of each plot. Progeny GS relative to parent average GS (mid-parent heterosis, MPH), and better parent GS (high-parent heterosis, HPH) were calculated on the basis of the mean GS over years and sites. Significant (P<0.05) line effects were detected, as were site, season, and year interactions. For the medium flowering date progeny, MPH and HPH GS ranged from -19 to 23% and -22 to18%, respectively. For the late flowering date progeny MPH and HPH for GS ranged from -9 to 25% and -15 to 21%, respectively. Some progeny exhibited significant (P<0.05) MPH and HPH. The five progeny with highest MPH values ranged from 14 to 23% and 10 to 25% for crosses within medium and late flowering classes, respectively. The same top progeny exhibited HPH ranging from 12 to 18% and 7 to 21% among medium and late flowering classes, respectively. A moderate, significant (P<0.05) negative correlation was observed between high GS of the better parent and the progeny’s level of HPH. However there were notable exceptions to the trend. The GS of the best progeny entry was significantly (P<0.05) higher than the GS of the best parent entry, indicating the potential of hybrid vigour to lift the yield barrier in PRG. Investigation is needed of the genetic, wider biological, and economic context under which a hybrid breeding system may be justified.
Since this oration is in the name of Sir Bruce Levy, I took the time to Google his biography and found it in the Te Ara Encyclopedia of New Zealand. Many of us are aware of his role as the Father of New Zealand Grasslands with his message of fertiliser, improved pasture cultivars and the efficient cycling of nutrients through grazing. But what interested me was his extension technique with farmers. This was described as akin to a sergeant major (Sir Bruce) dressing down the latest group of raw recruits (the farmers). It was clearly suitable for those times. Interestingly, Sir Bruce Levy, in taking his research findings out directly to farmers, was emulated by other notable scientists such as McMeekan and Brougham.
Decision Support Tools (DSTs) and models are becoming increasingly important to make informed decisions. The aim of this review was to understand how the scientific assumptions behind related pasture-based DSTs used in New Zealand interrelate. Using modelled feed intake of grazing sheep as a case study, we reviewed the metabolisable energy (ME) assumptions of relevant New Zealand models. Although the DSTs were largely dependent on a common model, there were some discrepancies between them. We raise two concerns: 1. In New Zealand, pasture-based livestock models to predict ME intake are highly dependent on equations developed in Australia, not validated in New Zealand. 2. The minor discrepancies between models make collaboration difficult – this is particularly pertinent to farmer-targeted DSTs. Closer collaboration between DST companies and research institutions is required to agree on consistent, robust equations aligned with the latest scientific knowledge.
This paper quantifies the effect of inoculation and lime on lucerne growth and nitrogen fixation over the establishment and following season. The field experiment at Ashley Dene, in Canterbury, had an initial soil pH of 5.2 and moderate exchangeable aluminium content (4.2 mg/kg). The 15N natural abundance (δ15N) method was used to quantify nitrogen fixation. The pH of the top-soil was increased to ca. 5.5 and the Al content was decreased to 2.0 and 1.3 mg/kg soil by the application of 1 and 2 t lime/ha, respectively. In Year 0 the dry matter yield increased from 3 to 4 t DM/ha with the addition of 2 t lime/ha. The nitrogen content of lucerne plants was 2.2% (w/w), and was unaffected by inoculant or lime in Year 0. Similarly, the δ15N was 0.81‰ and unaffected by inoculant or lime. In Year 1, the N percentage of inoculated lucerne plants was 4.2% (w/w) compared with 3.6% in uninoculated plants. The δ15N value was 0.81‰ in uninoculated plants compared with -0.23‰ in inoculated lucerne plants. The inoculated lucerne yielded 7.8 t DM/ha compared with 2.4 t DM/ha when uninoculated. The calculated proportion of legume N derived from atmospheric N2 (%Ndfa) estimated that 70% of the nitrogen content in the inoculated lucerne shoots was derived from nitrogen-fixation in Year 1. There was no effect of lime on lucerne DM, or δ15N values in Year 1. This suggests lucerne rhizobia tolerated moderate levels of Al in acidic soils. The application of lime and inoculant are therefore recommended for lucerne, particularly in areas where there is no history of lucerne. The available soil N was sufficient to meet crop demand in the establishing year. Lucerne was then reliant on biological nitrogen fixation for yield in Year 1 which suggests lucerne preferentially used soil available N in Year 0, before commencing N fixation. Keywords: Aluminium, lucerne, lime, Medicago sativa L., nitrogen fixation.
Hyperspectral sensing using ground-based equipment has been demonstrated to be successful in determining pasture nutrient content (N, P, K, S) and parameters such as dry matter content and metabolisable energy. This technology needed to be up-scaled so that large areas could be rapidly covered with adequate spatial resolution. This paper describes work which demonstrates a progression from hyperspectral sensing to hyperspectral imaging which utilises the visible, near infrared and short wave infrared parts of the electromagnetic spectrum. Large scale calibration and validation field trials were conducted at the same time as hyperspectral imaging was completed. These trials demonstrate the feasibility of producing information, in detailed map form, on pasture nutrient concentration and other parameters to inform fertiliser placement decisions as well as other farm management tasks. The technique effectively produces a forage analysis for every square meter of any farm. Keywords: hyperspectral imaging, precision agriculture.
The link between dairy farm systems and cost of environmental compliance is not always clear. A survey of Waikato dairy farmers was conducted to establish the real (non-modelled) cost of compliance with environmental regulation in the region. Quantitative and qualitative data were gathered to improve understanding of compliance costs and implementation issues for a range of Waikato farm systems. The average oneoff capital cost of compliance determined through a survey approach was $1.02 per kg milksolids, $1490 per hectare and $403 per cow. Costs experienced by Waikato farmers have exceeded average economic farm surplus for the region in the past 5 years. As regulation increases there are efficiencies to be gained through implementing farm infrastructure and farm management practice to best match farm system intensity. Keywords: Dairy, compliance, farm systems, nitrogen, Waikato
2014: Only a month ago it was Election Year. In the run up to the election we started to debate what is important to New Zealand; sadly that moment has long since passed. Will we ever have the great national debate that we sorely need? where does New Zealand pitch itself on the world stage and how we ensure that is possible? Sustainability in all its facets.
Spatial variation in pasture yield within a single paddock can be high. Measuring this variation has many potential benefits. For instance, cost-effective targeted treatments could be applied to low yielding areas resulting in increased pasture yield at a paddock scale with minimal cost. Understanding pasture yield variation requires tools that can measure it, and practical methodologies to guide how and when to use these tools to obtain useful data. The study reported here aimed to develop measurement protocols for using the C-Dax pasture meter to map yields of rotationally grazed pastures. The general principles should be applicable to other measurement tools. The pattern of pasture yield varies throughout the year. Because growing conditions change with the seasons, areas of a paddock that perform well in summer may perform poorly in winter, and vice-versa. Time of year is therefore an important consideration for measurement purposes. The recommended protocol developed from this project to estimate the spatial variation in annual yield on a paddock is to: • map 1 month following peak pasture growth rates; • drive at up to 50 m run spacings, but close enough to cover all features of interest; and • map as close to the grazing event as possible within the final third of the regrowth period. Keywords: Yield mapping, pasture, precision agriculture, pasture height, dairy, spatial management
The potential animal performance and greenhouse gas (GHG) abatement benefits from pastures and wide-spaced poplars on a typical lower-North Island sheep and beef farm operation were explored using farm-scale models. The analysis included reductions in understory pasture production, increased ewe reproductive performance (i.e., lambing and weaning percentage) with additional tree shelter and increased dry matter intake from poplar foliage. The pasture-tree systems demonstrated reductions in sheep stocking rates and total meat production, but increases in ewe efficiency and emissions intensity, reflecting a shift in feed energy use from maintenance to production. Inclusion of ewe fecundity and supplementary feed benefits largely overcame reductions in stocking rate and meat production due to pasture shading. An integrated assessment of the multiple benefits of pasture-tree systems should be incorporated in future farming scenario testing, strengthening our knowledge on the impacts of these systems compared with pastureonly systems. Keywords: pasture-tree systems, animal performance, greenhouse gas emissions.
Persistence of herbage yield is an important productivity trait of grass species and cultivars in New Zealand pastures. However, relatively little is known about genetic variation in this trait, principally because few studies comparing yield have continued beyond 3 years. This paper reports results from a comparison of 25 perennial ryegrass cultivars representing a wide range of functional types and genetic backgrounds conducted under sheep grazing in a summer-dry environment. Dry matter (DM) yield was measured for the first 3 years after sowing, then again in years seven and eight post-sowing, and in year ten post-sowing. Endophyte DNA fingerprinting conducted mid-way through year seven confirmed that, with one exception, ryegrass populations remained true-to-type in the cultivars sown with novel endophyte strains. The cultivar effect on DM yield was statistically significant in all measurement periods. Differences in yields among cultivars in years seven and eight were significantly and positively correlated with yield differences in years one to three (r=0.685 to 0.831 depending on which year contrasts were used). Thus, high-performing cultivars in the early years of the trial were also generally highperforming cultivars in years seven and eight, and vice-versa, indicating a high degree of yield stability in perennial ryegrass cultivars. Yield differences did not appear to be related to differences in cultivar heading date, ploidy, endophyte status, or genetic background. The relationship between yield in year ten and yields in years one to three was much weaker (r=0.392) than the relationship in years seven and eight. Possible reasons for this are discussed. Keywords: Perennial ryegrass; traits; persistence
Efficient effluent management allows capturing of nutrient benefits while reducing potential environmental impact. In New Zealand research has focussed on ponds and land disposal, whereas digesters are being implemented overseas. When biogas produced by anaerobic digestion is collected, it can be used to produce heat and electricity; this has been done in some countries trying to increase their renewable energy profile (e.g., France), but the cost is not always offset by the benefits. Analysis of policies concerning power supply in France and New Zealand revealed very large differences between the two countries, which, in combination with differences in population density, availability of co-digestion products and dairy shed effluent type, means that the establishment of biodigesters is unlikely in New Zealand unless there are changes in policy to encourage greater renewable energy via implementation assistance. Keywords: Biodigester, co-digestion, energy
How does the pasture cover at the beginning of lambing and the grazing strategy used in early spring influence the ability of a hill country sheep and beef farm to finish lambs? The results from an intensive pasture-mowing trial investigating three defoliation intensities (Lax, Moderate and Intense) starting from two herbage masses (1200 or 1500 kg DM/ha) during early spring were used to provide data on potential pasture consumption and feed quality from lambing to weaning for a breeding ewe flock. Using simulation modelling, this pasture data was used to estimate the potential lamb and ewe liveweight changes from birth to weaning at each of three different stocking rates (4.5, 8 and 10.5 twin-bearing ewes/ha) that closely represented the three defoliation intensities originally studied in a mowing trial. The impacts of these early-spring herbage masses and grazing intensities/ stocking rates on subsequent feed requirements and potential lamb finishing during the later summer and autumn period in four contrasting geo-climatic regions of New Zealand were then further investigated using simulation modelling. Variations in ewe and lamb weaning weights were evident and reflected the amount of pasture available through the different grazing management approaches. For all four geoclimatic regions studied, the Intense grazing, high stocking rate strategy generally produced the greatest gross revenue per ha from lamb sales out of the three grazing strategies investigated, though not significantly greater than the moderate stocking rate in summer dry environments. However, under Intense grazing, a high pasture cover (1500 kg DM/ha), in comparison to a low pasture cover (1200 kg DM/ha) at the start of ewe lactation further improved the gross revenue received from lamb sales, especially in the Canterbury and Waikato environments but less so in the Hawke’s Bay and Southland environments. These variations demonstrate how iterations based on the same starting properties impact on weaning weight of lambs and post-weaning pasture growth and/or feed quality. Keywords: emergence, feed supply, geo-climatic regions, iteration, lactation, lamb weaning weight, pasture quality.
Paddock selection is an important component of grazing management and is based on either some estimate of pasture mass (cover) or the interval since last grazing for each paddock. Obtaining estimates of cover to guide grazing management can be a time consuming task. A value proposition could assist farmers in deciding whether to invest resources in obtaining such information. A farm-scale simulation exercise was designed to estimate the effect of three levels of knowledge of individual paddock cover on profitability: 1) “perfect knowledge”, where cover per paddock is known with perfect accuracy, 2) “imperfect knowledge”, where cover per paddock is estimated with an average error of 15%, 3) “low knowledge”, where cover is not known, and paddocks are selected based on longest time since last grazing. Grazing management based on imperfect knowledge increased farm operating profit by approximately $385/ha compared with low knowledge, while perfect knowledge added a further $140/ha. The main driver of these results is the level of accuracy in daily feed allocation, which increases with improving knowledge of pasture availability. This allows feed supply and demand to be better matched, resulting in less incidence of under- and over-feeding, higher milk production, and more optimal post-grazing residuals to maximise pasture regrowth. Keywords: modelling, paddock selection, pasture cover
This will be considered under the topic headings that were submitted.
The development process from floral bud formation to seed maturity of four top flowering annual clovers was quantified from a field experiment across 10 sowing dates at Lincoln University, Canterbury, New Zealand. For each species, a numeric reproductive scale was created as a field guide to document morphological changes as the bud progresses through reproductive development. The duration from bud visible to open flower was 341 °C days for ‘Cefalu’ arrowleaf, 215 °C days for ‘Bolta’ balansa, 196 °C days for ‘Prima’ gland and 186 °C days for ‘Mihi’ Persian clover. The inflorescence then required a further 274-689 °C days, 185 °C days , 256 °C days and 425 °C days for each respective species to reach physiological maturity. This was indicated when 50% of seeds had turned red/brown for ‘Cefalu’ arrowleaf, 100% pods turned yellow for ‘Bolta’ balansa, 100% of seeds were yellow and hard for ‘Prima’ gland, and pods turned brown with the first sign of colour change in seeds for ‘Mihi’ Persian clover. These results can be used to facilitate on farm decision making in relation to grazing management or seed set for subsequent regeneration. Keywords: floral development chart, harvest maturity, peak flowering, pollination, seed filling, thermal time, Trifolium vesiculosum, T. michelianum, T. glanduliferum, T. resupinatum
Throughout 2014, the Manawatu-Wanganui Regional Council and DairyNZ worked with 10 farm consultants assisting dairy farmers preparing farm plans for the regional OnePlan and reducing their risks of contaminating local waterways. Twenty-three farm plans that had been produced with the support of five farm consultants were examined. Starting with average annual leaching losses of 23–71 kgN/ha, these plans included a range of mitigation practices to achieve reductions in nitrate losses of 5–15%. Although they had been developed independently, similar practices were bundled together in the plans to match the needs of each farmer’s circumstances and particular farming systems. This work suggests that although a short list of mitigation practices may be able to be selected for application on farms, the impact of those practices upon each farm business will each need to be determined in order to reliably enhance farm sustainability and viability across a catchment. Keywords: consultancy, OnePlan, consents, farming systems
New Australian-bred cultivars of subterranean (sub) clover with high levels of hardseededness are being promoted in New Zealand based on their superior performance in Australia. These new cultivars may not be suited to cooler New Zealand conditions. The “soft” seeded sub clover ‘Denmark’ dominated the hardseeded cultivar ‘Rosabrook’ in the second year of a dryland grazing experiment near Lincoln (630 mm mean annual rainfall), but in autumn of the third year the ‘Rosabrook’ population recovered to contribute 30% of total sub clover plants. A second field experiment, sown in March 2014 at Lincoln University, compared 10 sub clover cultivars sown with cocksfoot. ‘Antas’, ‘Narrikup’ and ‘Woogenellup’ were most productive at the September 2014 harvest. ‘Antas’, ‘Woogenellup’ and ‘Leura’ had the highest dry matter yields at the November 2014 harvest. In autumn 2015 ‘Narrikup’ re-established most seedlings and ‘Antas’ the least. Until we have better knowledge of the production and persistence of “new” sub clover cultivars under New Zealand conditions, farmers are urged to sow binary mixtures (50:50) of a “new” plus an “older” cultivar. Keywords: cocksfoot, Dactylis glomerata, grazing experiment, hardseededness, re-establishment, Trifolium subterraneum
High-sugar perennial ryegrass cultivars (HSG) selected for higher concentrations of water-soluble carbohydrate may enhance animal production and reduce emissions of methane and nitrogen. Assessing the effects on economic output and environmental footprint is most robust when related to production per unit of land. Average daily gain (ADG) and liveweight gain per hectare (LWG/ha) of sheep grazing a high-sugar perennial ryegrass cultivar, a diploid perennial ryegrass and a tetraploid perennial ryegrass were compared during measurement periods conducted in spring (84 days duration), autumn (99 days) and late springsummer (160 days). Continuous variable stocking was used, and stocking rate adjusted to maintain a target sward surface height of 6 cm. Average daily gain was higher (P=0.003) on the HSG than on either control in late spring-summer and higher on the tetraploid control than on the HSG or the diploid control in autumn (P=0.04), but the higher ADGs did not translate to significantly higher LWG/ha. These results can inform farmers on cultivar choice and support analysis of methane and nitrogen emissions on an intensity basis for inventory and regulatory purposes. Key words: water-soluble carbohydrate, perennial ryegrasses, high-sugar ryegrass, average daily gain, liveweight gain
In the northern half of Northland, perennial ryegrassbased pastures have exhibited poor persistence. Nineteen tall fescue and ryegrass pastures in the region infected with either MaxP or AR37 fungal endophytes, respectively, had high levels of endophyte-infected tillers and low levels of contamination from wild endophytes. On surveyed farms, MaxP-infected tall fescue pastures had good contents of sown grass, which were higher than sown grass contents in AR37-infected ryegrass pastures, but on two far-north monitor farms these temperate grasses failed to compete with summer active C4 grasses such as kikuyu and carpet grass. For tall fescue and perennial ryegrass to form productive pastures in this region, sown seed should have high levels of viable endophyte, soil fertility should be adequate for good grass and legume growth, and pastures should be well managed. Summer droughts may still be too severe in some years for these temperate grasses to persist in the face of C4 grass competition. Keywords: Endophyte, Epichloë, Neotyphodium, Lolium perenne, Festuca arundinacea, soil fertility
The effect of perennial ryegrass sowing date on dry matter (DM) yield and endophyte presence in the resultant pasture was investigated in 2014. ‘Trojan’ perennial ryegrass with NEA2 endophyte was sown on three separate occasions (20 February, 20 March and 27 April 2014) into a Kaipaki peat loam soil in a replicated plot trial on a dairy farm near Cambridge, Waikato. The first two sowings were in dry conditions and neither showed any sign of germination until after 45 mm of rainfall on 4 April (43 days and 15 days after sowing, respectively). Endophyte infection in established plots was measured on 17 December 2014. Yield was also measured from sowing until no difference was seen between treatments, in October 2014. Percentage endophyte infection was not affected by sowing date. Establishment was significantly faster in the February and March sowings, prior to rain, and these produced ca. 2 t DM/ha more than the April sowing giving an estimated total profit advantage of $646/ha. Keywords: endophyte, Epichloë festucae var. lolii (formerly Neotyphodium lolii), perennial ryegrass, Lolium, seed storage, sowing date, NEA2
Experiments in the laboratory, glasshouse and in the field assessed the chemical and agronomic characteristics of four polymer-coated urea products manufactured to different specifications, by altering the number and chemical nature of the coatings. (The chemical and physical nature of the coatings and the coating process are the property of the New Zealand distributor, Eko 360 Ltd.) They are claimed to be controlled release nitrogen (N) fertilisers. The N release characteristics of the experimental products were measured, relative to water soluble urea, in the laboratory in the absence of soil. These results confirmed that the N release rates were consistent with the distributor’s specifications and were slower than urea. A glasshouse experiment was designed to use N uptake by ryegrass as a proxy for the N release rate in a soil. These results confirmed those from the laboratory, indicating that soil had little effect on the relative N release characteristics of the fertilisers. The experimental product with the slowest release rate was selected for evaluation in the field. In three field experiments the effect the experimental product, applied once at two rates, on pasture production was compared with the same rates of N applied once as urea, over 5–6 months. The experimental product tested increased N use efficiency (NUE, kg DM/kg N applied) by between 5–50% depending on the site and rate of N application. Thus it is concluded that the products are as claimed – contolled release N fertilisers, relative to urea – and that this characteristic is expressed under field conditions. Proof-of-concept was therefore established. Keywords: fertiliser, nitrogen, nitrogen use efficiency, pasture, SmartFertTM, urea
Three on-farm sites where plantain was sown with legumes and/or perennial ryegrass were monitored for 2 years post-sowing. On two cultivated sites in Hawke’s Bay, newly sown plantain/clover pastures produced 20% and 22% more dry matter, respectively, than newly sown ryegrass/clover or established pastures. On an uncultivatable site in coastal Wairarapa, aerially oversowing of plantain and clover resulted in 282% more dry matter than resident pasture on north faces. Plantain pastures had higher clover contents and lambs had faster growth rates and higher dressing-out percentages than lambs finished on traditional ryegrass/clover pastures. Plantain and a mix of annual and perennial clovers offer a promising alternative to ryegrass-based systems in dryland. As with lucerne, plantain and erect annual clovers need to be rotationally grazed to prevent damage to the crown and growing points. The success of these alternative forages in dryland farming systems will depend on farmer willingness to embrace new grazing management techniques. Keywords: forages, plantain, arrowleaf clover, Persian clover, balansa clover, white clover, red clover oversowing, live weight gain.
The New Zealand dairy industry has increased significantly in size in over the last two decades. One of the drivers that has made this intensification possible is the use of maize silage as a feed supplement. Growing maize on farm imposes production and opportunity costs on the farm business. Opportunity cost was calculated using data from DairyNZ as the profit foregone due to not milking from the maize-growing hectares. Opportunity cost was added to Pioneer’s calculated cost of maize silage production to represent the cost that is incurred for each hectare of maize silage that is planted on farm. The true cost of maize silage grown on farm at differing milksolid (MS) payout levels and farm systems was estimated. The findings indicate the economic appropriateness of growing maize silage on farm depends upon the farm system, the value of MS and the cost to purchase maize silage in a given year. Keywords: Maize, milksolid payout, opportunity cost
Wai’ra’rapa – The place Maori called “Land of Glistening Waters”. Wairarapa is a region of big skies, wide valleys rolling hill country and rugged coastline. It has a total land area of 8423 square kilometres. The region is named after Lake Wairarapa, which situated at the bottom of the Wairarapa Plain, North of Palliser Bay. Wairarapa is located on the South Eastern Corner of the North Island bounded by the Pacific Ocean in the East, Tararua district in the North and the Tararua Ranges in the west.
The challenge of maximising the value of an onfarm investment is dependent on two factors: first, ensuring the full potential of the investment is realised by adjusting current practices to capture the gains; and second, the challenge of isolating, quantifying and valuing the contribution that investment makes to the whole farm business. A new generation farm optimisation model (INFORM) addresses both these issues. Two distinctly different on-farm investments, planting of a forestry block and sowing a multi-year forage crop, both on a hill country sheep and beef operation, are presented to illustrate the capability the model has for first optimising the investment and then using this information to conduct a farm system capital investment investigation. The investment analysis includes consideration of the capital requirements, and also calculates the maximum amount that can be spent on each of the investments to add value to the current business. Keywords: farm system analysis, investment, NPV, optimisation, INFORM
Recent work which genotypically characterised rhizobia of native, crop and weed legumes in New Zealand and examined their cross-nodulation ability is reviewed and related to earlier work with focus on New Zealand pasture systems. The New Zealand native legumes were exclusively effectively nodulated by novel strains of Mesorhizobium which did not nodulate crop or weed legumes. Clovers, lucerne, Lotus and grain legumes were effectively nodulated by different genera, species and biovars of rhizobia primarily originating from inoculum. Rhizobial symbionts of white clover have established over wide areas in New Zealand. Weed legumes are effectively nodulated by different genera/ species of rhizobia depending on species. Bradyrhizobia that cross-nodulate lupins, gorse, European broom and tagasaste are widespread in New Zealand. Keywords: Bradyrhizobium, Burkholderia, Ensifer, Mesorhizobium, Rhizobium
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