Journal of New Zealand Grasslands

The impact of a forage plant breeder – the story of Herrick Sydney (Syd) Easton (1946 - 2023)

2023-05-24T04:51:54+00:00

Herrick Sydney (Syd) Easton was a forage plant breeder for 46 years. He bred at least 11 forage cultivars, in ryegrass, tall fescue and lucerne that were successfully licensed and commercialised, and he was a key part of the team that developed the successful Epichloë fungal endophyte products ‘Endosafe’, AR1, AR37, and ‘MaxP’ (‘MaxQ’ in USA). Syd’s development of measurement techniques and documentation of genetic variation for potentially valuable novel traits has been detailed in 130 refereed and significant publications, and he was an inventor or co-inventor of 13 patents and/or Plant Variety Rights. Syd made an important contribution in the understanding of endophyte-ryegrass interactions. Through his innovation and leadership, he led the multi-disciplinary AgResearch endophyte research programme, coordinating and writing the first successful funding application that consolidated the team. Coming from a farming family Syd connected with farmers and understood the value of highly supportive farmers and agricultural professionals who were able to critique, understand the value of and use the technologies and knowledge delivered from the science research he was involved with. Like many others in the agricultural research profession, he gained immense satisfaction from seeing technologies resulting from his research being used on New Zealand farms.

Yield and growth rates of pastures grown in the Bay of Plenty region over 35 years

2022-04-28T04:17:51+00:00

Bay of Plenty district, and particularly the Rotorua Lakes area, has a diverse terrain and soil types which influence pasture production. Regular measurement of pasture production enables short term decision making on a farm scale and is invaluable for catchment,
district and regional long term management strategies. Thomas (Tom) M. Gee, was a retired farmer with more than 18 years of field trial experience with MAF Field Research Division. He collected data from more than 30 farms after he retired. Data from other sites in the district were collected in the early 1970s by MAF technicians stationed in Whakatane and Tauranga and later by AgResearch staff and a farm consultant based in Rotorua. Tom Gee’s mission was to use these measurements to provide farmers with rates of growth (ROG) data to inform them about their farm. The Gee farm (Fairbank) of 200 ha was originally leased from Ngati Whakaue Tribal Lands in 1916 and then purchased before much of it was sold back to the Incorporation in 1970. Tom retired in 1989 but kept meticulously recording pasture growth rates on different farms up to ~ 2007. Some field notes were lost, but datasets with gaps are still useful to assist monthly growth rates calculations. His valuable and extensive (almost 25 years) on farm field records have been retrieved, compiled, assembled, and digitised, to be saved electronically, and entered into the AgYields National Database hosted at Lincoln University. Part of this legacy dataset has been summarised and dry matter yields and growth rates calculated, consistent with
previous methods, to provide a quantified description of mean monthly pasture growth rates across the Bay of Plenty region, in New Zealand.

Implications of changing birth and slaughter dates of finishing sheep and beef cattle on greenhouse gas emissions

2023-07-18T01:06:32+00:00

Significant variables in the calculation of greenhouse gas (GHG) emissions are estimates of birth date and slaughter date, as these alter the amount of time on-farm and hence feed used for animals destined for slaughter. Analysis of Beef + Lamb New Zealand Economic Service farm survey data calculated average birth and slaughter dates for both finishing sheep and beef cattle at a regional scale, from 1990-2019. Data were then used to calculate the potential GHG emissions related to lambs and slaughter cattle, and changes over time, and were compared to current national inventory calculations. There was no significant change in sheep
mating date over the 30-year period, with a median lambing date of 10 September. Beef cattle mating date became later over the 30-year period. These resulted in calving dates of 20 September for the 1990-2000 period, and 25 September for the 2010-2019 period.
The proportions of lambs slaughtered by February (early) or October (late), categories used by the National Inventory, have shifted from 84 and 16% respectively in 1990 to 78 and 22% recently. The ages at slaughter of 1–2-year-old heifers and steers were approximately 24 and 35 days younger in 2019 than in 1993 (528 vs 552 days of age at slaughter for heifers and 520 vs 555 days of age at slaughter for steers). The changing proportion of lambs slaughtered early and late had a small effect on total emissions. Later birth dates and earlier slaughter dates have reduced the individual emissions from 1–2-year-old cattle, but individual emissions from older
cattle and bulls have changed little over the 27-year period examined.

Genetic modification – benefits and risks for New Zealand grassland production systems

2023-06-28T03:16:01+00:00

Fundamentally plant breeding is about expanding and exploiting the genetic potential of plants (Stoskopf et al. 2019). Over time this has included amongst others phenotypic selection, mutagenesis, genetic modification (GM) and now gene editing (Bowerman et al. 2023). In many crop species genetic modification has been a valuable option for delivering improved economic and environmental outcomes. However, while genetic modification has been extensively used in crops for 25 years it has rarely been a technology used to advance trait expression in forage and grassland species. Worldwide, GM technologies have been adopted at a faster rate than any other recent crop technology (Raman 2017; Scheitrum et al. 2020). Despite the large government investment into GM technologies for use in grass and forage plants it has not used outside of containment in New Zealand (Caradus 2008).

The aim here is to review why New Zealand has been so reluctant to use GM technologies as another means of providing solutions for the pastoral sector. Traits manipulated using a range of genetic modification techniques that might have application and benefit in grassland systems will be reviewed, and regulatory concerns that need to be considered when adopting GM forage and pasture plants will be discussed. Interestingly, 70 to 90% of GM crop production globally is used for animal feed (Flachowsky et al. 2012; Ritchie and Roser 2021). So if animals across the world, including those in USA, China and Europe are being fed GM crops (Baulcombe et al. 2014) why would New Zealand be concerned about using GM pasture plants? Although over a decade old, a useful summary of views from a variety of stakeholders is provided by the New Zealand Institute of Agricultural & Horticultural Science (AgScience 2010).

Are observed rates of productivity compared to model predictions indicating negative climate impacts in perennial plants?

2023-07-27T22:25:32+00:00

Understanding the apparent discrepancy between observed and modelled primary production is explored in this paper using long-term pasture and radiata pine (Pinus radiata) growth data sets and relevant biophysical models. To better understand the historical trends on primary production from pastoral agriculture and forestry, annual net herbage accumulation (NHA) and total volume yield was modelled (APSIM and PPM88) and compared with long-term pasture and forestry data sets from key regions in New Zealand.

Ballantrae and Poukawa (Southern and Central Hawke’s Bay) showed declining trends in NHA (observed and modelled), over the last 20 years. In contrast, Woodlands and Waikato have shown no changes or a slightly increase in NHA despite large changes in management practices and nutrient inputs, particularly at the Waikato site. In Kaingaroa Forest in the central North Island empirical models have overestimated tree growth and volume production in recent years relative to observations. The minimal changes or decline in vegetation growth challenge the prevailing notion of expected increases in vegetation growth under future climate scenarios.

Predicting facial eczema risks in a changing New Zealand climate

2023-06-26T01:22:45+00:00

Facial eczema is a major concern for New Zealand farmers due to its economic impact and animal welfare implications. The disease occurs when animals ingest sporidesmin, a mycotoxin produced by spores of the fungus Pseudopithomyces chartarum. Spore production is related to weather conditions; thus the incidence and severity of facial eczema varies between years, with the
disease commonly occurring from late summer through autumn in the North Island. We developed a simple model to estimate climatic suitability for P. chartarum sporulation and ran it using climate data for 2008-2021 to compare its estimates with spore counts from the same years. Model climatic suitability estimates had significant linear correlations with an index of exposure to spores derived from spore counts at both national and local scales. Model results were also consistent with a documented outbreak of facial eczema. Using predicted future climate data from the Hadley Centre Global Environment Model version 2 and two emissions
scenarios, the model suggested climatic suitability for P. chartarum sporulation will increase with time in many New Zealand regions, particularly in the southern North Island and eastern parts of the South Island. However, it could remain relatively static in some other areas, thus the degree of change in climatic suitability for P. chartarum sporulation is predicted to vary between New Zealand regions.

Condition of the soil resource and provision of ecosystem services from a Brazilian Oxidic soil under conventional and integrated livestock-based systems

2023-07-23T20:38:34+00:00

Integrated crop-livestock-forest systems promote soil health and deliver more ecosystem services (ES) compared to conventional livestock systems, although most studies on the subject poorly describe the soil component of these systems. This preliminary study
assessed the condition of the soil resource and its role in the provision of ecosystem services from a Brazilian Oxidic soil under conventional and integrated livestock-based systems. Five systems were studied from pasture only to partial and fully integrated croplivestock-forest systems. All are located on one of the Brazilian Agricultural Research Corporation (Embrapa) Research Farms. Data for the quantification of the soil resource and ES for each of these livestockbased systems were retrieved from previous studies
and used to quantify soil health, the provision of food and fibre and climate regulation, as well as report their impacts on receiving environment. Soil organic carbon content, a key component of soil health, was higher in the most integrated system. Soil-based grass yields were lower in integrated systems due to competition for resources from the trees or space taken by crops but had the highest overall provision of food and fibre. Carbon sequestration by trees in the integrated systems offsets enteric methane emissions from beef production, and this ES contributes to mitigating climate change. Future studies should include analysis of all the natural
resources and a wider range of soil-based ecosystem services, along with impacts on receiving environments
to provide a more complete picture of the performance of integrated livestock-based systems.

Challenges and opportunities for conducting on-farm research

2023-07-17T05:05:34+00:00

Availability of research farms owned by research institutions is declining due to their high operational cost, asset value, and limited distribution. The goals of this paper are to review their role and value in pastoral science and to identify challenges and opportunities for on-farm research. Research and commercial farms as trial sites may be mutually exclusive, complementary, or substitutes. Research farms are essential where science requires expensive facilities and/or rigorous control to maintain ethics and quality commitments. They can also provide information independent of scientific and commercial bias. Commercial farms provide access to more diversity, help scientists understand benefits and identify and resolve on-farm issues, and build industry credibility. Since the number of research farms is unlikely to increase, several lessons are important. Delivery, ethical, and science quality risks can accrue when the full cost of working with commercial farms is not considered or work most suited to a research farm is conducted in a commercial setting. Improved integration with farms owned by educational institutions; private trusts; regional and national government; and commercial companies offers opportunities for efficiency improvements. When working with commercial farmers, clear communication, flexible protocols, frequent oversight, and mutual respect are essential to maintain science quality. Paying farmers under a contractual agreement appears pragmatic. The value of opportunities to build farmer and researcher capability in the context of field experiments on research and commercial farms is identified.

Understanding pathways of digital technology development to improve farm sustainability and resilience.

2023-08-08T01:43:13+00:00

We explored potential pathways of digital technologies to improve both resilience and sustainability outcomes in grazing systems by investigating the development requirements of virtual herding technologies. We used a Lead User group familiar with virtual herding technology to examine the question “after virtual herding has been successfully adopted, what will the future look like”? This group included agribusiness, industry, corporate farm management, farmers, and science. A brainstorming approach generated ideas. A horizontal prototype was built by clustering ideas into themes of the technology itself, requirements of people, applications, and outcomes, allocated to short-, medium-, and long-term timeframes. Steps required for technology development included: production of a minimum viable product, integration of sensors, and the addition of landscape digitisation. The requirements/impacts on people identified training and awareness, development of skills and labour requirements, and the changing roles of people in the landscape as a progression of change. Applications included productivity, environmental protection, landscape development and enterprise change. A range of requirements were identified within each of these steps and categories. The development of a vision of future technology use provides insight into the complexity of developing digital technologies for sheep and beef farming applications.

Developing a multiagent framework to explore the implications of fencing waterways using virtual fencing on New Zealand hill country farms.

2023-05-31T04:51:45+00:00

Hill country farms in New Zealand are faced with having to exclude cattle from waterways to limit their negative impact on water quality. Virtual fencing technology offers the potential to control the access of each animal to its physical environment and, meet the requirement of excluding stock from waterways. Understanding farmer willingness to uptake virtual fencing technology requires exploring farm system changes that would occur when moving from using conventional fences to virtual fencing. This paper describes the investigation of a multiagent framework to explore potential futures that may be created by the application of virtual fencing technology. Compared to conventional fencing, virtual fencing of beef cattle on hill and steep land is a financially viable option to exclude cattle from waterways. Compared to no fencing of waterways, virtual fencing reduced farm annual profitability by 9% and 17% for rolling and steep farms respectively, whereas conventional fencing reduced profitability by 14% and 93% respectively, severely reducing the profit of steep hill country farms. The results from this study used industry sheep and beef production, farm size and
stock number averages and therefore are preliminary and indicative only.

Obstacles and opportunities for automation in sheep and beef farming

2023-05-31T04:47:44+00:00

Automation of tasks on farm has had limited uptake in tools such as auto-weighing and auto-drafting. To develop an understanding of the range of digital tools and the potential to automate tasks in the sheep and beef industry, workshops with end-users were held in the North and South Islands of New Zealand. Current digital technology use on sheep and beef farms included 26 applications representing the categories of communications, administration, monitoring, automated tasks, decision support, prediction, and proof of placement. Obstacles included the amount of time required to either set up or support the technology once in operation. Interoperability and the transfer of information between applications and along the value chain were major obstacles to generating value from combining digital technologies. Automation of data flows along the value chain would provide a significant step forward in the uptake of digital technologies. Digital solutions to aid automation need to be interoperable, with data able to be passed between software solutions, and between users to reduce compliance time and increase accuracy of data handling. The technologies need to be appropriate to be adopted on large scales in an automated way to capture labour-saving benefits. Automation solutions need to translate data into a decision-making form to allow easy interpretation and application of data.

Factors influencing pastoral farmers' land-use change decisions in response to environmental regulations in the Selwyn District, Canterbury

2023-06-05T21:28:14+00:00

In recent years, the pressure placed on New Zealand farmers to reduce their environmental impact and convert to more sustainable land-uses has significantly increased in response to public and political concerns. This has seen an increase in the amount and complexity of environmental regulations, particularly for farmers in the Selwyn District, Canterbury. Increasing environmental regulations has contributed to an unintended side effect of a declining relationship quality between farmers and regulatory authorities.

This study provides a new way for regulatory authorities to understand which factors influence pastoral farmers’ land-use change decisions and how these factors interact in response to environmental regulations. A total of nine pastoral farmers operating in the Selwyn District were interviewed to obtain data on how they made land-use change decisions and the impact of environmental regulations on these. Specifically, the data involved the collection of Q-sort scores, centrality scores, and the creation of causal maps.

This study found that financial factors were the most important to pastoral farmers when making land-use change decisions. However, these financial factors were strongly connected to farmers’ sense of certainty around policy and practice. Many farmers felt unsure about the impact of current and future policy and practice changes on their farms. Subsequently, they felt hesitant to make land-use change decisions without the confidence that it will remain a financially and strategically viable choice for the longer term.

This study also found that farmers had high intrinsic values surrounding environmental stewardship. Contrarily, environmental regulations drive land-use change decisions in an extrinsic form to farmers. This difference is concerning because if farmers become too focused on only doing what is required to meet regulations, it risks taking away the common-sense approach farmers already have. Overall, without improvements in the communication between regulatory authorities and farmers, the future may see increased focus by farmers on ticking boxes and less on strategically thinking about what is best for the environment.

In summary, improved understanding by regulatory authorities and actions resulting from this will greatly contribute to positive environmental outcomes being reached in an efficient manner. To encourage sustainable land-use change, regulatory authorities need to give increased thought on how future regulations are created and implemented long-term. Farmers will feel more confident to transition to more sustainable land-uses with increased certainty around policy and practice and regulations that are introduced to them in a way that better understands their role as environmental stewards.

Pukekauri farm – snapshots from a sustainability journey

2023-06-28T02:54:40+00:00

Pukekauri Farm is a 295 ha mixed livestock hill country property in the western Bay of Plenty. Over the last 20+ years the owners have been on a development journey with a focus on the multiple dimensions of sustainability – economic, environmental, and social. This paper seeks to document that journey, with supporting resource, production, financial and environmental data to quantify progress. Some of the most useful tools have included high quality forage crops, deferred grazing, sheep genetics, accounting software and paddock-scale soil and water resource maps. Key lessons include the value of knowledge networks and modelling tools, the power of a farm plan for optimising land use and management, the importance of both profitability and grants to underwrite development investment, and the emergence of secondary benefits from decisions focused on system-wide improvement. Over 20 years, despite a
reduction in grazed area of 20%, meat production has increased by 16%, EBITR/ha has increased by 6%, modelled net greenhouse gas emissions have declined by 60% and modelled N leaching has declined by 29%. Overall, the farm is easier to manage and more pleasant to dwell in.

Māori cultural values and soil fertility management – an exploratory study

2023-08-01T04:18:22+00:00

Collectively owned Māori farming entities work much of the remaining Māori freehold land in Aotearoa New Zealand (~5% of total) and the majority of these are registered in the Māori Land Court. The effective and sustainable management of these farms is vital to
landowners (e.g., whānau/hapū/iwi) whose prosperity is dependent on the wealth and strength of connection generated from this land (whenua), which is also a source of wellbeing. There are some distinct features of the institutional factors of Māori farms that impact on how they are managed. For example, because Māori land can never be sold (Te Ture Whenua Māori Act 1993), realising capital gain is not an option for Māori farmers. Māori farm managers hence focus on cashflow and profit within the farming operations, which can sometimes put pressure on important yet discretionary investment expenditures, such as fertiliser costs (Cottrell 2016). However, as nutrients are taken off farms through animal products, soil fertility management is fundamental to the replenishing of nutrients on farms to maintain productivity and profitability (Haynes and Williams 1993). Consequently, fertiliser costs take up a significant proportion of farm expenditure for most New ealand farms, impacting on their profitability (Hedley 2015). The retention and control of Māori land remains a top priority for Māori land managers, with whom the continuous provision of return through productivity or profitability is seen as essential for landowners (e.g., whānau), and the long-term sustainable management
and delivery of services is largely driven by cultural values. So, where does the balance lie between ongoing provision and potentially discretionary expenditure? The present research set out to explore the nuances behind such a question.

Deep insertion of lime into acid organic soils

2023-06-28T03:13:08+00:00

Organic (peat) soils are inherently acid in their natural state with soil pH levels that decline from 4.5 – 5.0 in the surface layer of 0 – 75 mm to 4.0 - 4.5 at a depth of 400 mm. Traditionally lime has been surfaceapplied and incorporated into the lower soil layers by
cultivation. An alternative method of inserting 3 - 4 t/ha of lime down to 400 mm soil depth was tested on a developing Waikato deep Moanatuatua Organic soil. When two-thirds of the lime was placed within the 300 - 400 mm layer and one-third within the 200 - 300 mm layer in summer 2021, soil pH in the 200 - 300 mm layer decreased from 5.6 in 2021 to 5.3 in 2023 and significantly increased from 4.2 to 4.9 in the 300 – 400 mm layer over the same time period. Reversing the ratio of the lime rate into the two layers resulted in a
significant increase in soil pH from 4.5 to 5.3 in the 200 – 300 mm layer and a non-significant increase from 4.2 to 4.6 in the 300 – 400 mm layer. Generally, there were corresponding decreases in soil exchangeable aluminium (Al) concentration in those layers. The ratio
of lime insertion rate had no significant effect on rooting depth between years. There was a moderate correlation between soil pH and exchangeable Al when measured at depths of 0 – 400 mm. These interim results indicate that the deep insertion of lime into an acid Organic soil was effective in increasing soil pH and reducing soil Al concentration in the lower soil layers in the two years after the lime was inserted.

An assessment of the agronomic effectiveness of N‐(n‐butyl) thiophosphoric triamide (nBTPT) - treated urea on the production of clover-based pastures, pastures, grasses and crops.

2023-08-31T03:10:22+00:00

Approximately 50% of the world’s population depends on nitrogen (N) fertiliser to secure a sustainable food supply. Improving the efficiency of nitrogen fertiliser – the nitrogen use efficiency (NUE) - is a major goal both nationally and internationally, driven by the need to reduce the environmental footprint of farming. One of the technologies developed for this purpose is the addition of the urease inhibitor, N-(n-butyl) thiophosphoric triamide (nBTPT), to urea, to reduce the volatilisation of ammonia from the soil. In this paper we report the results from field trials, recorded in the national and international literature, comparing the effects of nBTPT treated urea, relative to untreated urea, on plant dry matter (DM) yields (cloverbased pasture, grasses and arable crops) from 45 studies summarizing the results on a site × year × crop basis. For the aggregated data (n = 348) the marginal yield results were normally distributed around a mean of about 3% (95% confidence interval 0.9), with a range from -23% to +32%. The results for the various subsets (based on different crop types) of data were very similar. The size of the effect of nBTPT was related to the rate of N application.

Variation in kale and fodder beet yield and quality over winter affects nutrient supply to non-lactating dairy cows at the Southern Dairy Hub

2023-06-02T05:08:48+00:00

Estimating crop quality and quantity is important for feed budgeting and nutritional balancing of diets for winter grazing. Commonly, farmers measure crop dry matter (DM) yield in autumn, but few complete quality tests. We assessed the DM yield and quality of
late spring sown kale and fodder beet (FB) from early autumn to late winter over five years at the Southern Dairy Hub, Southland, New Zealand. Yield and quality parameters were analysed over time since sowing, using polynomial data fitting. We hypothesised that
crop yields would remain stable during winter grazing, but that the supply of nutrients would vary, driven by a decline in the leaf proportion. Overall, crops showed rapid growth prior to winter but stable yields during winter grazing, but there was year to year variation in apparent growth trends and yields. The proportion of FB bulb increased over winter relative to the total crop yield for all cultivars and years. Fodder beet leaf was numerically higher in multiple nutrient concentrations (crude protein, Ca, Mg, P, S) compared to the bulb. For both crops, nutrients had only small fluctuations in concentration over time. Completing yield assessments in late autumn would give farmers a useful baseline yield indication for winter. Crop quality tests are recommended to identify any nutritional deficiencies that need addressing to ensure good animal health and performance.

Fodder beet: know what you are feeding for a nutritionally balanced diet for dairy cattle

2023-05-26T01:26:39+00:00

Fodder beet’s (FB) high soluble sugar and low crude protein content provide environmental benefits but also nutritional challenges, making it a unique crop in New Zealand dairy systems. Knowledge of dietary nutrient content is important to inform both mineral
supplementation and type of supplementary feed to offer. This will help ensure nutritional requirements for dairy cows are met, maximising the likelihood of positive outcomes for animal health and production. A database containing 694 samples of FB leaf and
bulb tissue was compiled from monitor farm data, research projects, and cultivar evaluation trials with the objective of determining the variability in nutritional content. Descriptive statistics were used to highlight the range and variability in FB leaf and bulb nutritional composition between regions and cultivars. Our results reinforce that FB bulbs (which usually make up 70- 90% of the crop DM) are typically low in crude protein, fibre, phosphorus, calcium, and sulphur, but are high in soluble sugars. The variation in nutrient content between cultivars, and within cultivars both between and within regions shown in this study highlights the importance of paddock-specific feed analyses, and the limitations of textbook values, particularly whole crop values which do not differentiate between bulb and the more nutritionally valuable leaf.

Plantain (Plantago lanceolata L.) content within plantain/ perennial ryegrass (Lolium perenne L.) pastures may be limited by livestock treading damage

2023-05-31T04:54:43+00:00

TThere is evidence that plantain (Plantago lanceolata L.) persistence within perennial ryegrass (Lolium perenne L.) dominant dairy pastures is usually poor. One factor potentially limiting plantain content and persistence is treading damage, caused by cows grazing
pasture while the soil moisture content is high. The impact of treading damage on plantain regrowth and survival was investigated in two field experiments at Massey University, Palmerston North. In a small-plot study, cow treading damage was simulated on separate
plantain and perennial ryegrass pastures using a novel treading device. Subsequently, a larger-scale experiment investigated the impact of treading damage by grazing dairy cows on plantain regrowth and survival within a mixed plantain/perennial ryegrass pasture. Damage by the treading device, in late spring, immediately reduced the growth rate of both plantain and perennial ryegrass
pastures by 30%, however neither plantain content nor density were reduced. In experiment 2, treading damage reduced the growth rate of the mixed pasture by 50% in early spring but it recovered during late spring. Plantain content and density were both initially reduced by the treading damage treatment but recovered to pretreading levels by autumn. These results suggest that treading damage from cows may be an important cause of reduced plantain content in dairy pastures during spring, however there was no evidence that treading damage reduced plantain persistence.

Legume yield and persistence when sown in grass and herb pasture mixes in Lees Valley, South Island High Country

2023-08-01T04:26:57+00:00

Four experiments were established to identify suitable companion species for legumes grown in the intermontane Basin of the Lees Valley, North Canterbury (400 m a.s.l.). This location experiences long cold winters, has soils of low pH and high aluminium, with low water holding capacity and severe summer soil moisture deficits.

In Year 1, the ryegrass mixtures yielded 4550±290 kg DM/ha more (P<0.05) than the timothy mixtures (3440 kg DM/ha) and the dryland mixture total yield was 4370 kg. The average white clover yield of 1800±210 kg DM/ha was not different among all treatments and represented 43% of total DM, compared with only 8% for sub clover.

Total yield in Year 2 was higher (P<0.05) in the dryland- and ryegrass-based mixtures (~4400±330 kg DM/ha) than timothy (2650 kg). White clover yield across the mixtures was 930±90 kg DM/ha and 29% of the total DM. Sub clover did not re-establish.

White clover yields peaked in October-November of both years with growth rates of ~16 kg DM/ha/d. The start of the summer dry period, from late September onwards, resulted in a decline in white clover spring growth rates and lower yields.

In the Caucasian-herbs experiment, yield in Years 1 and 2 were 2700±250 and 2830±230 kg DM/ha/yr respectively. In both years Caucasian clover yields were lower when grown in herb-based mixtures compared with a monoculture (Year 1: ~400 versus 1800±270 kg DM/ha, Year 2: 920 versus 1750±210 kg DM/ha). The herb content of the mixtures declined over time.

Yield and persistence of legume monocultures grown in the Lees Valley, South Island High Country

2023-05-23T09:25:20+00:00

Six legume monocultures were established in the Lees Valley, North Canterbury (400 m a.s.l.), which has long cold winters. The stony soils have low pH, high aluminium concentration, and low water holding capacity, which can lead to severe summer soil moisture
deficits. The aim was to identify legumes that would survive and persist in this environment and, therefore, increase the available nitrogen in the pastoral system. Legume populations of 88±12 seedlings/m2 were established and ranged from 45 (sub clover) to 197
seedlings/m2 (Caucasian clover). The highest yields were from ‘Pawera’ red clover at 2.5 and 2.9 t DM/ha in Years 2 and 3, ‘Demand’ white clover produced 1.7 and 2.6 t DM/ha, and ‘Endura’ Caucasian 1.8 and 1.7 t DM/ha. ‘Kaituna’ lucerne yields were low at 0.7 and 1.4 t DM/ha. Caucasian clover was the most persistent legume. A visual assessment in Year 5 found Caucasian was the only legume still dominating its plot (69%) with the lowest area of bare ground (11%). ‘Leura’ subterranean and ‘Bolta’ balansa annual clovers survived for four years but accumulated annual yields were low (<1.0 t DM/ha/yr), and the presence of unsown species was high (>50%). While red and white clover provided the highest yields for two years, Caucasian clover was the most persistent species and is
therefore a legume recommended for this environment.

Hill Country Futures - Resilient farmers and resilient forages for the future

2023-08-01T04:40:19+00:00

A thriving hill country farming sector is crucial for New Zealand’s economy and its regions. However, it faces numerous challenges, such as increased regulations, and changing societal expectations. To ensure the longterm success and well-being of farmers, farm systems, the environment, and rural communities, support is essential for building lasting resilience. To address some of these challenges, the Hill Country Futures Partnership programme was initiated, receiving $8.1 million funding over five years. This programme, cofunded by Beef + Lamb New Zealand (B+LNZ), the Ministry of Business, Innovation and Employment, PGG Wrightson Seeds, and RAGT New Zealand, concluded in 2023. During the programme, the farming community were actively engaged, and a collaborative research approach was employed involving B+LNZ, farmers, universities, Crown Research Institutes, and consulting agencies. The programme consisted of interconnected workstreams with a focus on resilient farmers and future-oriented forages. It generated a wide range of resources, including easily accessible extension materials, tools, and scientific publications, covering social, environmental, and technical aspects to support New Zealand’s hill country farming systems. And it showed how a collaborative approach, inclusive of researchers and farmers with diverse backgrounds and expertise, can help create a more resilient hill
country future.

Predicitng yield of irrigated red clover (Trifolium pratense L.) pastures in response to temperature.

2023-08-06T21:04:52+00:00

Two datasets from red clover monoculture pastures grown in Lincoln, New Zealand, were analysed to generate coefficients to predict red clover yield. The mean annual production of established red clover was 17.0±0.48 t DM/ha, with a maximum mean growth rate of 125±9.36 kg DM/ha/day (spring Year 2). In the establishment year irrigated red clover grew at a constant rate of 7.30±0.14 kg DM/ha/°Cd (Tb = 3 °C) throughout the year. In contrast, there was a splitline linear response in Years 2 and 3, which differed between years and decreased after the second week of January. Specifically, the growth rate in Phase 1 was 7.70±0.38 kg DM/ha/°Cd in Year 2, which was 16% higher than the 6.60±0.28 kg DM/ha/oCd in Year 3. The difference probably reflected increased competition from weed grasses as red clover content declined from >95% to ~75% of total annual yield. After January, red clover grew at 3.05±0.35 kg DM/ha/°Cd, in both years. This lower rate occurred in the mid-January-July period, and probably reflected a change in partitioning of assimilate to red clover roots in response to a decreasing photoperiod. The coefficients reported here for red clover need to be validated from other datasets. However, they provide easily transferable coefficients that can be used to estimate red clover yield under nonlimiting conditions for other locations. These could be integrated into feed budgeting software to assist onfarm decision making.

Five-year old diversified pasture delivers greater lamb liveweight gain than a standard perennial ryegrass-white clover pasture

2023-05-31T04:21:33+00:00

This study investigated liveweight gain of lambs grazing five-year-old pasture of either Italian ryegrass, red clover and plantain (Diversified) or perennial ryegrass and white clover (Standard). Coopworth lambs were born to either diversified or standard pasture and reared there until weaning in December (early summer). Liveweight gain (LWG) from tailing to weaning was 23% higher in lambs on diversified pasture (0.335 kg LWG/lamb/day) compared to those on standard pasture (0.272 kg LWG/lamb/day). From summer to autumn (December to May), liveweight, pasture mass, botanical composition and nutritive quality was measured as weaned lambs progressed through rotationally grazed paddocks of either diversified or standard pasture. Similar lamb liveweight gain between
pasture types was observed over summer and autumn, with both groups averaging 0.187 kg LWG/lamb/day. From December to May, dry matter intakes (DMI) and feed conversion efficiencies (FCE) were similar between lambs grazing on either diversified or standard
pasture. Average final lamb liveweight off diversified pasture was 4.2 kg higher than off standard pasture. The higher pre-weaning liveweight gain and subsequent greater weaning liveweight off diversified pasture was maintained throughout the summer and autumn.

Drought impacts African black beetle feeding on perennial ryegrass

2023-06-19T03:36:10+00:00

interactions between plants, herbivorous insects and fungal Epichloë endophytes. However, water availability fluctuates, a phenomenon intensified by climate change, challenging the success of New
Zealand’s pastoral industry. The impacts of climatic changes, such as intensifying drought, on pastoral insect pests have received little attention. In a no-choice bioassay, African black beetle (ABB) were fed semi-synthetic diets containing freeze-dried foliage material from drought-exposed and well-watered perennial ryegrass containing endophyte strains AR37 or NZCT, or with material free of endophyte (Nil). Diet consumption, beetle weight change, fungal alkaloid concentrations, phytohormones, and NRI (nitrogen reflectance index) concentrations were measured and compared. Except for AR37, ABB consumed more diets containing drought-exposed rather than well-watered material, with a 61% increase in Nil and a 50% increase in diets containing NZCT, though these effects were not accompanied by corresponding ABB weight changes. Here, we discuss the implications of these results on ABB damage in New Zealand pastures in the context of increasing drought and illustrate how spatial patterns of ABB damage could change over the next 75 years. Areas that do not currently have high populations of ABB such as Manawatū-Whanganui, Wairarapa and Marlborough will become increasingly vulnerable to damage.

Pasture growth curve impacts the economic merit of extended lactation: a simulation study

2023-08-16T20:32:45+00:00

Voluntarily increasing the calving interval beyond 12-months (extended lactation; EL) has possible benefits in reducing labour requirements, herd replacement rate, and surplus calf numbers. With limited information on feed balance and economic effects with EL, reductions in profitability were hypothesised. A MS Excel spreadsheet model was developed to compare calving systems: spring calving annually (Base), two herds between spring and autumn calving with 18-month calving intervals (EL18), or two herds calving in alternating springs with 24-month intervals (EL24). Weekly feed balances using pasture growth curves for four regions (Northland, Waikato, Canterbury, Southland) and partial budget analysis informed estimations of supplement costs and net income (NI). The EL24 system had lower supplement costs (-$240 /ha) and higher NI (+$439 /ha) than the Base system for Northland only. The EL18 system
always had the highest annual milk production and total revenue, but highest supplement costs and lowest NI in the four regions. Replacement, calving, and mating costs were lower for EL systems than Base; however, costs for milking and repairs and maintenance were higher. This preliminary study indicates there is merit in investigating EL systems, particularly for Northland. Further data from EL systems are needed to increase confidence in the system’s potential.

Farm-level cost-effectiveness analysis of in-paddock feeding of methane inhibitors in pasture-based dairy

2023-06-08T02:22:48+00:00

Various approaches have been proposed to reduce methane emissions from ruminant livestock systems. While methane-inhibiting feed-additives are not yet commercially available in New Zealand, it has been reported that they can reduce enteric methane emissions by 30-90% when fed to ruminant livestock regularly and precisely in total mixed ration systems. This study aims to determine the primary economic performance drivers of using In-Paddock Smart-Feeders (IPSF) for delivering methane inhibitors in pasture-based dairy to understand the conditions in which they are viable. A farm-level financial model is developed, drawing on the Economic Farm Survey produced by DairyNZ. Both a scenario and sensitivity analysis are conducted on the cost-effectiveness of the approach for methane mitigation. The main finding is that the largest cost associated with the approach is the cost of additional
supplement, which would acts as a carrier for the methane inhibitor. Therefore, the quantity of additional supplement used prior to adoption is a key determinant of viability. There is a large range in breakeven methane prices depending on the value of assumptions
used. More certainty in these assumptions is required to fully understand the potential use of IPSFs to deliver methane-inhibiting feed-additives in-paddock.

Grazing management practices on Waikato and Canterbury dairy farms diverging in bulk milk urea content

2023-06-26T02:23:40+00:00

New Zealand dairy farmers have little realtime information on surplus nitrogen (N) in their herd’s diet to help manage farm-scale N loss. By understanding the influence of management on bulk milk urea (BMU), farmers could potentially use milk components to identify changes in dietary N surplus. Our study examined the relationships between grazing management and BMU concentration on 38 dairy farms selected for low or high BMU in Canterbury and Waikato. Measurements included pre- and post-grazing herbage mass, perennial ryegrass leaf stage at grazing, and botanical and chemical composition (crude protein (CP) and metabolisable energy (ME) content) of herbage on four occasions over a year. Herds with Low BMU tended to graze pastures with a greater pre-grazing herbage mass (+153 kg DM/ha), a more advanced leaf stage (+0.13 number of leaves), and longer grazing intervals (+11 days). Consistent with this, herbage on Low BMU farms had lower CP (-2.7%) compared with High BMU farms. We identified grazing management differences between Low and High BMU groups, which could be linked to reductions in N surplus in the herd’s diet through the lower CP% of pasture offered. Future work should determine the importance of this in relation to other farm management factors such as
supplement and N fertiliser use.

Co-benefits and trade-offs of water quality mitigation measures on greenhouse gas emissions from New Zealand dairy systems

2023-07-17T05:16:39+00:00

As part of government climate change policy, New Zealand dairy farmers will be encouraged to reduce their greenhouse gas (GHG) emissions through a proposed pricing mechanism. With integrated farm plans on the horizon, farmers need information on how mitigations for water quality will impact GHG emissions. Using a typology approach that captured the main production attributes and drivers of nitrogen (N) and phosphorus (P) losses to water we assessed the impact of 12 current N and P contaminant mitigations on GHG co-benefits or trade-offs. Four of the mitigations had a co-benefit effect, with most of these being N mitigation measures.
Trade-offs were detected for two water quality mitigations (stand-off pads and deferring effluent application), resulting in an increase in estimated GHG emissions. The remaining six water quality mitigations tested, either had a minimal impact, or had both a tradeoff
and co-benefit. Our data provides pastoral farmers and rural professionals with information to guide initial conversations on options to reduce losses to water and air for developing integrated farm plans

Stacking nitrogen leaching mitigations in a Canterbury dairy system whilst minimising profitability losses.

2023-07-04T05:40:23+00:00

The aim of this project was to model combinations (“stacks”) of cost-effective nitrogen (N) leaching mitigations within a dairy system that could reduce N leaching by 40-60%, whilst minimising losses in profitability. A FARMAX and OverseerFM combination was used to model a baseline farm representing a typical Canterbury system, and seven sequentially “stacked” mitigated systems. The mitigations were combined and stacked in the following order based on mechanism(s) of action, practicality, and cost-effectiveness: 1) reduced synthetic N fertiliser input (from 190 to 100 kg N/ha/year); 2) including Italian ryegrass in the pasture sward; 3) including plantain in the pasture sward; 4) earlier calving and drying off (by 10 days); 5) wintering on pasture and baleage; 6) standing cows off-pasture;
7) using new-generation nitrification inhibitors. The most cost-effective stack combined mitigations 1 to 5. We estimated that N leaching was reduced by 57% relative to baseline, with an 8% reduction in operating profit. Greenhouse gas emissions were reduced by 8%. The largest single reduction in N leaching was from stack #5, and it coincided with no/little change in milk production pasture eaten and had no capital cost. A careful selection of complementary mitigations could achieve significant reductions in N leaching without compromising greenhouse gas emissions and, to any great extent, profitability.

Using leaf regrowth stage to define defoliation interval for diverse pastures of complementary species (Lolium perenne L., Bromus valdivianus Phil., Dactylis glomerata L. and Trifolium repens L.)

2023-06-19T03:20:27+00:00

Diverse pastures of complementary species (DPCS) comprise species that fulfil different agroecological niches, resulting in growth asynchrony and complementarity of functional roles. It is expected that DPCS have a greater capability to tolerate and perform
under increasingly extreme climate events, providing a potential alternative for New Zealand pastoral systems. In the present study, DPCS comprised Lolium perenne L., Bromus valdivianus Phil., Dactylis glomerata L., and Trifolium repens L. The leaf regrowth stage [LS; L. perenne (2.5-3.0LS), B. valdivianus (3.5-4.0LS) and D. glomerata (3.5-4.0LS)] is proposed to be an applicable method of defoliation management for DPCS due to a potential overlapping of the defoliation interval. The seasonal and annual herbage mass accumulation and botanical composition of DPCS and their respective single-grass and T. repens pastures under the LS criterion were assessed. The annual yield did not differ among pastures (average 20.26 t dry matter (DM) ha- 1). However, significant differences were found within seasons, with DPCS exhibiting asynchronous growth among species that reduced the seasonality of herbage
accumulation and invasion by volunteer species. Lolium perenne, B. valdivianus and D. glomerata were shown to be complementary grass species, presenting growth asynchrony and an overlapping defoliation interval that optimised production, indicating that defoliation based on LS criterion is a suitable management for DPCS.

Incorporating plantain into ryegrass-white clover mixed sward for an economically and environmentally sustainable dairy system: Year one of a farm system study

2023-06-14T22:28:15+00:00

The objective of this replicated farm system study was to investigate the effect of increasing proportion of plantain (Plantago lanceolata L. cv. Ecotain) in a perennial ryegrass/white clover (RGWC) mixed sward on farm productivity, profitability and environmental footprint over the 2021/22 production season. A total of 108 dairy cows were blocked into nine herds of 12 cows.
The herds were randomly allocated into one of three replicated pasture treatments sown with an increasing plantain seed rate: (i) RGWC with nil plantain (PL0); (ii) RGWC+3 kg/ha plantain seed rate (PL3) or (iii) RGWC+6 kg/ha plantain seed rate (PL6). Farmlet milk
and pasture production were measured, and data was used to estimate farm profitability and environmental footprint using FARMAX and OverseerEd software, respectively. Increasing plantain seed rate from 3 to 6 kg/ha increased sward content of plantain from
24% to 34% of DM in PL3 and PL6, respectively. Pasture production (average 12,988±473 kg DM/ha), total milksolids production (1,356±40 kg/ha) and farm profitability (4,347±354 NZ$/ha) were similar amongst treatments. Compared to PL0, estimated annual nitrogen leaching and nitrous oxide emissions were reduced by 21% and 30%, (P<0.001) and 4.3% and 6.0% (P<0.01) in PL3 and PL6, respectively. Results suggest that incorporation of plantain into dairy systems could be used as a strategy to reduce predicted
environmental footprint while maintaining profitability. However, these results need to be confirmed over multiple production seasons.

The case for expanding the range of subject specialists used in farm planning.

2023-06-19T03:18:35+00:00

We explored the merit of expanding the range of subject specialists used in farm planning. We document the outcomes for sheep and beef farmers to improve water quality and promote climate change awareness as part of the wider planning process in two community catchment groups (Hurunui District Landcare Group and King Country River Care group). We found that subject specialists added value. A land resource specialist contributed to greater precision and a more detailed description of the farms natural and built capital. This contributed to a more robust analysis and better targeting of the actions in the work programme. The terrestrial ecologist activated the link between the management of indigenous biodiversity and stream health, with resilience to future climate events. The carbon specialist created the link between tree planting and water quality outcomes because of where tree plantings were located on most farms. The carbon specialist also highlighted the option to register existing soil conservation plantings under the emissions
trading scheme, adding a revenue stream. With the subject specialist(s) as part of the wider farm team, environmental concerns are more likely to be integrated into the business plan with mitigation actions better tailored and targeted in the work programme.