2024 Pasture Variety Trials Results

Chad Hall, South Coastal Agencies

Introduction

2024 marked the fifth and final year of the ASHEEP & BEEF Pasture Variety Trials, a Meat & Livestock Australia (MLA) Producer Demonstration Site (PDS) project. As part of this initiative, South Coastal Agencies (SCA) collaborated with sheep and cattle producers to assess pasture performance across diverse management systems, soil types, and rainfall zones. The primary objective was to evaluate pasture productivity, stocking rate potential, and production costs, providing an economic analysis for each scenario. Pasture selection was guided by rainfall classification, with zones categorised as high (+550mm), medium (350mm), and low (<350mm).

The 2024 season proved to be one of the most challenging years in recent history for livestock producers in the Esperance region. Producers were forced to provide supplementary feed for most of the year, while sheep prices plummeted to record lows. To further compound the issue, destocking options were limited, as processors withdrew from the market and breeders showed little appetite for investment due to severe feed and water shortages and an end date to live export was officially announced. These harsh conditions were acknowledged and reflected in the PDS trial. While such adversity makes drawing clear conclusions more difficult, it provided valuable insights into which pasture varieties can persist and perform under extreme conditions.

Method

The ASHEEP & BEEF Pasture Variety Trials began in 2020, with years one and two being plot trials to determine suitable varieties for trial in larger commercial broad-acre trials conducted in years three, four, and five. These broadacre trials were to be planted by producers for the purpose of grazing under normal conditions and stocking rate and, by doing so, testing the varieties under pressure. At each location, three pasture grazing cages were constructed to facilitate livestock (sheep or cattle) grazing in the paddock while enabling continuous monitoring of pasture growth and nutritional value. Upon installing the cages, visual observations were recorded, encompassing aspects such as pasture composition, establishment, and the presence of noteworthy pests like mice, diamondback moths, and mites.

The break of the season was determined for each site by recording the date of the first opening rain, a rainfall event greater than 10mm in 24 hours. While in the 2022 demonstration sites, only ten and sixteen-week pasture cuts were taken for analysis, ASHEEP & BEEF and SCA determined that in subsequent years a third cut should be taken at twenty weeks where appropriate biomass was present to represent the entire season better and pinpoint peak biomass production throughout the year.

Pasture samples were extracted from a quadrant and sent for analysis. Each pasture sample underwent weighing to ascertain both wet weight and available biomass, allowing the determination of kilograms of dry matter per hectare (Kg/DM/Ha). The pasture cuts were uniformly trimmed from the same quadrant each time to simulate livestock grazing with subsequent regrowth closely monitored. Observations and notations were made regarding the presence of weeds, insects, diseases, and alterations in pasture composition.

Analysis

In 2024, the analysis of pasture performance placed greater emphasis on each variety's ability to overcome drought conditions, rather than solely comparing input costs or carrying capacity across rainfall zones as in previous years. With many sites experiencing severe moisture stress, the focus shifted toward evaluating which pastures could not only survive but continue to produce meaningful biomass under limited rainfall. Dry matter yields and pasture growth rates were assessed relative to the actual rainfall received, providing a clearer picture of water use efficiency and drought resilience. Nutritional quality, including crude protein and metabolizable energy, was also considered across the season to determine which pastures maintained feed value as conditions deteriorated. While the cost per DSE and nitrogen fixation were still calculated, they were used to support a broader understanding of how effectively each pasture could adapt and respond to extreme seasonal pressure, offering insight into their long-term reliability in a variable climate.

NIR Analysis

A Near-Infrared Reflectance Spectroscopy (NIR) analysis measures feed quality to ensure that the feed is adequate for the livestock grazing a pasture. Considerations that are used in this report are that a single DSE requires 8.3 megajoules (MJ) of metabolisable energy (ME) and at least 9% crude protein (CP) per kilogram of dry matter consumed to maintain condition (pregnant sheep and lambs require 15% CP). All figures used in this report are based on Dry Matter measurements. A description of all measurements has been included below.

Moisture and Dry Matter (DM%) – These two figures add up to 100% and are the inverse of each other. They are the percentage of moisture removed to the percentage of DM remaining.

Crude Protein (CP%) – The most used measure of proteins available from the feed source. CP% is calculated from the nitrogen content in the plant material.

Acid Detergent Fibre (ADF) – ADF measures less digestible fibres, cellulose, and lignin. This can be used to measure digestibility or how much of the DM is useful. The higher the ADF content, the lower the digestibility.

Neutral Detergent Fibre (NDF) – NDF is a prediction of all digestible and indigestible fibre contained by the feedstuffs. This encompasses all the ADF but includes the highly digestible fibres, hemicellulose, and pectin. Feeds with NDF levels that are too high will reduce dry matter intake, and too low will reduce roughage and digestibility.

Lignin – Lignin is a component of both NDF and ADF that is entirely indigestible. It acts to bind up nutrients that would otherwise be available to the animal. Lignin aids in plant stem rigidity by binding cells to the cell wall; the plant uses this mechanism to strengthen its stem in preparation for reproduction. Abiotic stresses to the plant, such as water, heat, and nutritional stress, will cause lignin biosynthesis, which can prematurely reduce the feed quality.

Metabolizable Energy (ME) – This is the measure of ME/kg of DM and is a simple calculation of gross energy minus energy losses in faeces, urine, and gases.

Pasture Growth Rates (PGR) – PGR is the amount of feed grown per hectare per day, measured in kilograms of DM/ha/day over a set period.

Total DM/Ha – All the dry matter measured over the period.

PGR AVE – The average pasture growth rate (kgDM/ha/day) over the period of measurements.

Total Digestible Nutrients (TDN) - A measure of the energy content in pasture, representing the total amount of digestible fibre, protein, carbohydrates, and fat. It’s expressed as a percentage of dry matter and indicates how much usable energy livestock can obtain from the feed.

Growing Season Rainfall – The rainfall collected from the 1st of January to the 1st of September; this was when the final pasture samples were taken.

2024 Project Results

Site: Gibson, Diaman2ti Bladder Clover

Leigh and Karina opted to trial Diaman2ti Bladder Clover in 2024, selecting the variety for its hard-seeded characteristics with the aim of achieving long-term pasture persistence and resilience in the event of a false break. Diaman2ti is well suited to low-to-medium rainfall zones and has an early to mid-maturity window, generally flowering between 90 to 100 days after germination. This early phenology was expected to improve its tolerance to dry finishes, aligning with the region’s typical rainfall pattern of late winter and early spring.

Diaman2ti had previously performed exceptionally well in the 2021 PDS plot trials, where it was recognised for both its visual appeal and strong biomass production. In comparison to older bladder clovers, which have often failed to persist beyond the first year, Diaman2ti was seen as a promising improvement in terms of both regeneration and productivity.

However, seasonal conditions were far from ideal. A dry start to the year led to patchy and sparse germination, resulting in poor establishment by the 10-week mark. This was reflected in the first pasture cut, which recorded only 523 kg/ha of dry matter. The stand remained immature, with a DM% of 15.7 and crude protein (CP) still high at 25.7%. The metabolizable energy (ME) was measured at 10.01 MJ/kg, and total digestible nutrients (TDN) came in at 63.8%, indicating a reasonable feed quality but very limited yield.

By the 16-week assessment, rainfall had improved, allowing the early-germinated plants to put on more growth and triggering a second wave of germination. Unfortunately, the staggered establishment led to significant weed competition, which further reduced overall pasture performance. At this stage, dry matter content increased to 16.7%, and the crude protein had dropped to 17.6% as the pasture began to mature. ADF and NDF levels rose to 27.5% and 29.1%, respectively, which is typical of plants moving beyond their most digestible growth phase. ME remained stable at 10.2 MJ/kg, and TDN lifted slightly to 64.9%. Importantly, DM yield had increased substantially to 3,117 kg/ha, with an average pasture growth rate of 44.53 kg DM/ha/day.

Despite this late-season recovery, the increasing weed burden ultimately forced a management decision to spray the pasture out to prevent further weed seed set. The remaining biomass was baled for summer feed in an effort to salvage some value from the paddock. A hay sample was collected and tested, showing a DM% of 90.4%, as expected for dry forage. Crude protein dropped further to 11.1%, while ADF and NDF increased to 33.3% and 51%, respectively, indicating reduced digestibility. ME also declined to 9.37 MJ/kg, with TDN falling to 60.4%.

While Diaman2ti showed good potential, especially in its ability to recover and produce dry matter later in the season, the trial highlighted several key risks. The dry start significantly hindered establishment, and the delayed germination left the pasture vulnerable to weed competition. Once moisture did arrive, the pasture was able to respond well, but forage quality declined with increasing plant maturity. The recovery came too late in the season for the pasture to be carried through, and weed management ultimately became the priority.

In conclusion, Diaman2ti Bladder Clover has potential for use in low-to-medium rainfall areas due to its hard-seeded traits and capacity to recover after dry conditions. However, its success is heavily dependent on early rainfall for even establishment. Future use may benefit from tighter weed control, possible sowing adjustments, and better early-season conditions to help the pasture reach its full potential.

Site: Cascade, RM4 Vetch

In the 2024 season, RM4 vetch was once again subjected to extreme early-season dryness, and it continued to demonstrate its reputation as a resilient and reliable pasture species. Known for its woody stem structure, small leaf area, and deep root system, RM4 vetch is particularly suited to challenging environments where moisture is limited. These physical characteristics support both persistence and productivity under seasonal stress, and this year’s results reaffirmed their adaptability and value to livestock systems.

Rainfall during the early part of the year was significantly below average, with only 57.5 mm recorded from January through to May. These conditions would typically limit germination and early plant development. However, rainfall improved in July (50 mm) and August (52.5 mm), providing the necessary moisture for pasture growth. By September, rainfall had dropped back to just 12 mm, effectively signalling the end of the growing season.

Despite the dry start and relatively short growing window, RM4 vetch still achieved a total dry matter yield of 4,026 kg DM/ha across three pasture cuts. These samples, taken at 10, 16, and 20 weeks after the break, revealed consistent and high nutritional value across the season.

At the 10-week cut, the crude protein content of the pasture peaked at 30.6%, with total digestible nutrients (TDN) at 70.3% and metabolisable energy (ME) measured at 11.22 MJ/kg. Although the dry matter percentage was relatively low (22.1%)—a reflection of high moisture content at this growth stage—the feed quality was excellent.

By 16 weeks, crude protein dropped slightly to 29.6%, but digestibility improved. TDN reached 72.1%, and ME climbed to its highest level at 11.55 MJ/kg. This mid-season period also marked the peak in biomass production, with 1,937 kg DM/ha recorded and a pasture growth rate of 27.67 kg DM/ha/day. These gains align closely with the more favourable rainfall received in July and August.

At 20 weeks, crude protein increased again to 31.8%, possibly due to the concentration of nutrients as the plant matured. However, TDN dropped slightly to 69.3%, and ME also declined, likely due to increasing fibre and moisture content. Dry matter accumulation fell to 1,034 kg/ha, reflecting the slowdown in growth due to declining soil moisture and reduced rainfall in September.

RM4 vetch’s performance this season highlights several important traits. Its capacity to accumulate more than 4,000 kg/ha of dry matter in a dry year speaks to its drought resilience and suitability for low-rainfall zones. The variety maintained excellent feed quality throughout the trial, with consistently high crude protein and digestibility levels, attributes not often seen in pasture species as they mature. Notably, the strongest growth coincided with periods of increased rainfall, showing that RM4 is capable of quickly taking advantage of improved conditions, even following a dry start.

Overall, RM4 vetch once again proved itself as a valuable pasture species in mixed farming systems, especially in regions with variable or limited rainfall. Its structural and physiological traits support establishment under pressure, while its ability to produce and maintain high-quality feed throughout the season makes it a reliable option for producers. This year’s results further reinforce its place as a dependable, high-performance legume in challenging conditions.

Site: Condingup, RM4 Vetch

Traditionally, this site has been more prone to waterlogging, with average annual rainfall typically around 550 mm. However, conditions in 2024 were significantly drier, with the site receiving only 365 mm across the entire year. From January through to September, just 283 mm of rainfall was recorded, reflecting a well-below-average season.

RM4 vetch was sown on the 19th of March, following a small break that provided just enough surface moisture for germination. From that point onward, the site experienced an extended dry spell, with limited rainfall until early June. Despite these challenging conditions, the 10-week biomass cuts, taken on the 10th of June, revealed that RM4 vetch had produced 1312 kg of dry matter per hectare, having received only 38.8 mm of rain since sowing. This result equates to a water use efficiency (WUE) of 33.8 kg DM/ha/mm of rainfall, a particularly strong outcome under low-rainfall conditions.

The ability of the crop to perform under such moisture-limited conditions can likely be attributed to a combination of contributing factors. These include some carryover of subsoil moisture from earlier in the year, the strong root establishment characteristics of the RM4 variety, and the use of a nutritional program that supported early development. In addition, moderate temperatures throughout autumn were favourable for biomass accumulation, and above-average solar radiation, averaging 12.6 MJ/day, supported photosynthesis and sustained growth despite minimal rainfall.

It is also hypothesised that RM4 vetch exhibits lower evapotranspiration (ETo) demand than other pasture species during early establishment. This may be attributed to RM4 vetch’s higher root-to-shoot ratio and relatively small initial leaf area, which enables the plant to prioritise root development and access moisture from deeper in the soil profile during early establishment. In contrast, species such as clover typically allocate more energy toward early leaf growth while maintaining a shallow root system. This growth pattern makes them more responsive to light rainfall events but also significantly more vulnerable to false breaks and early-season dry spells. During the early stages of the RM4 trial, ETo levels averaged 3.76 mm/day. This indicates that the atmosphere was placing a high evaporative demand on the system, effectively removing up to 3.76 mm of water per day from a fully watered crop. Under these conditions, RM4's ability to persist and grow is particularly notable.

Following rainfall in June, the pasture responded strongly. Subsequent biomass cuts at weeks 16 and 20 recorded yields of 2561 kg DM/ha and 2432 kg DM/ha, respectively. Over the measured period, RM4 vetch produced a total of 6305 kg of dry matter per hectare from 229 mm of rainfall, demonstrating a water use efficiency of 27.53 kg DM/ha/mm for the period.

The feed quality across all sampling points was high, with sufficient energy and protein levels to support all classes of livestock, including growing, finishing, and lactating animals. The combination of dry matter yield, drought resilience, and feed quality highlights RM4 vetch as a highly adaptable and productive option for mixed farming systems in low to medium rainfall environments.

Site: Condingup, RM4 Vetch & Dargo Ryegrass

This site was located in close proximity to the previously discussed Condingup trial and experienced very similar seasonal conditions. The key difference in this trial was the inclusion of Dargo ryegrass in the pasture mix, introduced to take advantage of early rainfall if it occurred.

Through earlier observations, we’ve learned that RM4 vetch performs exceptionally well in tough starts, largely due to its growth habit, which favours root development over leaf growth early on. This allows the plant to access deeper soil moisture and reduces vulnerability to evapotranspiration (ETo). However, this trait, while advantageous in dry seasons, does limit RM4's ability to generate large volumes of early feed when the season starts softly and moisture is more abundant.

In contrast, ryegrass is well known for its ability to rapidly produce biomass under favourable early-season conditions. Although it is more susceptible to false breaks and can suffer from reduced growth during dry spells post-germination, ryegrass will thrive and bulk up quickly when supported by consistent moisture (as seen in the table below). This makes it a strategic inclusion for early feed supply.

The vetch and ryegrass combination also offers an advantage in grazing systems. As previously discussed, vetch is less palatable than many other pasture species, meaning livestock tend to preferentially graze the ryegrass early. This selective grazing gives vetch the opportunity to establish undisturbed. Once established, RM4 vetch is capable of producing substantial dry matter in a relatively short timeframe, especially in late winter or spring.

In this particular trial, however, the ryegrass component did not get the opportunity to fully express its potential due to the season. This is evident when comparing the 10-week biomass cuts between this trial and the earlier RM4-only trial, where the differences in early-season yield are minimal.

While 2024 may not have been the year for ryegrass to truly perform, the mixed pasture still demonstrates several key benefits. It provides a balanced approach to early grazing, maintains strong feed quality, and offers drought resilience by combining two species with complementary growth patterns. Overall, this pasture system builds greater resilience through species diversity, making it a valuable strategy for variable rainfall environments.

Site: Cascade, Experimental Mix of Santorini Serradella, Arrow-leaf Clover, Megamax Panic Mix, Splenda Seteria Grass, Howlong Cocksfoot, Rasina Vetch, Ryecorn

This diverse pasture mix was sown as an exploratory trial to identify which varieties were best suited to the local environment, relying on natural selection to guide future pasture selection decisions. As such, it was not established with a focus on immediate return on investment, but rather to inform and improve broader program planning. Under the seasonal conditions experienced in 2024, the outcomes aligned closely with expectations. Ryecorn performed consistently across all soil types, Santorini established well on the sandier areas, and vetch thrived in the heavier soils.

Due to dry conditions throughout April and May, the decision was made to delay seeding until June 18th. By this time, moisture levels had started to improve, but both soil and air temperatures remained well below ideal for crop establishment. These cool conditions significantly slowed germination and early root development, potentially leading to reduced plant populations and heightened vulnerability to pests, frost, and weed pressure.

One of the key factors behind the slow start to pasture establishment was the reduced enzyme activity resulting from low soil temperatures. Enzymes play a vital role in driving the metabolic processes essential for germination, particularly the breakdown of stored starches and proteins within the seed into usable sugars and amino acids. These compounds fuel cell division, root initiation, and shoot emergence. In temperate pasture species such as clovers, ryegrasses, and cereals, optimal soil temperatures for these enzymatic reactions generally range from 10–15°C, with legumes often requiring the higher end of that range. When temperatures fall below this threshold, enzyme function slows considerably, leading to delayed energy release and sluggish radicle and shoot development. This results in staggered germination, uneven seedling emergence, and slower canopy formation, which increases the pasture’s vulnerability to weed pressure, pest damage, and moisture stress during the critical early stages of establishment.

While diverse pasture mixes offer many agronomic and ecological benefits, one of the key challenges is the limited in-crop weed control options. Management is largely restricted to strategic grazing and, in some cases, the use of a wick wiper, though this is only effective when weeds grow taller than the pasture species. This limitation became apparent at the 10-week assessment, where significant weed competition and aphid pressure were observed.

By 16 weeks, the pasture had begun to senesce, despite being sown later in the season. Stress factors, including insect pressure from budworm and aphids, were evident during biomass cuts, with visible damage to seed pods and flowering structures. Unfortunately, by the 20-week mark, there was very little pasture left to assess.

This season posed considerable challenges, particularly at this site. Despite the difficult conditions, the pasture did manage to produce some in-season biomass. However, due to insect damage, it is unlikely the pasture will persist into the following year.

Site: Grass Patch, Pallinup Oats & Morava Vetch

This pasture was sown in mid-June and remained ungrazed throughout the season. Oats were included in the vetch mix to boost early biomass and reduce the time to first grazing. Unfortunately, this site recorded the lowest rainfall of the entire trial, resulting in extremely challenging growing conditions.

At the 10-week assessment, biomass levels were too low to measure. However, by 16 weeks, the pasture had produced 7,597 kg of dry matter per hectare. Despite this yield, energy and crude protein levels were only marginally within acceptable ranges. Given the tough season and the heavy demand on supplementary feed in 2024, the pasture was ultimately cut for hay in an effort to replenish feed reserves. This hay will prove valuable during the upcoming summer.

Economic Analysis and Comparisons

In a year marked by extreme price volatility across the Western Australian livestock industry, managing the cost of production has become not just prudent, but essential. With tightening margins, producers must now assess every hectare and every dollar spent to ensure maximum economic return. Although a common mistake here is to pull back on inputs altogether, this can be detrimental to profitability, rather, we must consider our return on investment for every dollar spent on inputs to ensure that we are maximising profitability and managing risk.

The ASHEEP & BEEF Pasture Trials were established to provide valuable insight into how pasture systems performed under the seasonal pressures. With a focus on grazing efficiency, cost-effectiveness, and return on investment (ROI), this report aims to assist producers in identifying strategies that offer both resilience and profitability.

While these figures provide valuable insights, it is essential to consider the context and management strategies behind each outcome. In the case of the Diaman2ti bladder clover, the Wests established the pasture as a nursery crop and opted for a robust seeding rate of 10 kg/ha. This naturally increased the cost of production. However, under a more favourable season, this paddock had the potential to yield up to 500 kg/ha of pasture seed, with a market value of $13/kg, equating to a potential return of $6,500/ha, not including the early grazing opportunities that could have been realised.

Unfortunately, seasonal conditions limited the crop’s ability to meet its intended purpose. Recognising this, the Wests pivoted and made the decision to cut the pasture for hay later in the season. This move not only helped to reduce weed seed set for the following year but also allowed them to rebuild depleted hay reserves following a difficult summer.

A similar strategy was employed by the Vandenberghe’s, who also chose to cut their pasture for hay. Despite producing impressive biomass, the crop matured too late in the season to be effectively utilised as a grazing resource.

While these decisions fall outside the scope of the current economic analysis, they highlight the importance of adaptive management. When seasonal conditions disrupt the original plan, being able to shift direction can reduce risk and help protect long-term profitability.

Another important consideration is that the cost of establishing a pasture could potentially be amortised over three to five years, particularly if the pasture is set up to regenerate and self-establish in subsequent seasons. However, for the purposes of this analysis, we have focused on achieving a return on investment within the first year.

Pasture Performance & Persistence

Despite below-average rainfall in many trial locations, several pastures performed strongly in terms of biomass and grazing support. Notably, the Grass Patch trial (Oats + Morava) demonstrated excellent productivity and grazing efficiency, supporting over 31 DSE/ha, indicating strong persistence and effective utilisation of late-season rainfall.

The Cascade Pasture Mix site recorded lower DSE/ha outcomes and higher cost per unit of grazing. These results should not be viewed as failures, but rather as reflections of how seasonal conditions, establishment timing, and soil type can significantly influence pasture performance. One of the inherent advantages of using a diverse pasture mix is that, over time, natural selection tends to favour the species and varieties best suited to the specific environment. These better-adapted species are more likely to persist and thrive, while those less compatible gradually decline in dominance. This strategy has helped the Pengilly’s have confidence in selecting varieties for their broader pasture program in the future.

Additionally, many pasture species, particularly hard-seeded legumes, have the ability to remain dormant in the soil seedbank until seasonal conditions become favourable for germination. This trait offers a form of biological insurance, allowing the pasture to express its full potential across multiple years.

It’s important to acknowledge that pasture variety selection always involves a degree of uncertainty. Without knowing what the season will deliver, growers are often required to make informed decisions based on long-term goals, local experience, and a willingness to take calculated risks.

The two charts, Cost per DSE Day ($) and DSE per 100 mm of Growing Season Rainfall (GSR), highlight key differences in how effectively each pasture system converted inputs and rainfall into usable grazing. These measures provide a more practical lens on profitability than total yield or biomass alone, focusing instead on the cost of maintaining livestock and the efficiency of rainfall use.

Cost per DSE Day

Cost per DSE day is a particularly useful metric for benchmarking pasture systems against the alternative cost of supplementary feeding. In most commercial scenarios, feeding pellets to maintain a DSE typically costs between $0.80 and $1.20 per day, depending on ration quality and freight.

By comparison, the Grass Patch (Oats + Morava) trial delivered exceptional grazing value at just $0.04 per DSE day, demonstrating how strategic pasture systems can deliver comparable animal maintenance at a fraction of the cost. Even allowing for variability in utilisation or grazing efficiency, this represents an extremely cost-effective system.

Other strong performers included the Gibson (Diaman2ti) and Condingup RM4 vetch trials, which maintained DSE day costs of $0.19 and $0.13, respectively. These represent highly competitive alternatives to hand feeding, especially when considering reduced labour and delivery costs.

At the higher end, the Cascade Pasture Mix trial recorded a cost of $0.54 per DSE day, bringing it closer to the range of manufactured feed. While still potentially viable in a well-integrated system, the margin for error is narrower and demands better grazing utilisation to justify the higher cost base.

DSE per 100 mm of GSR

When viewed through the lens of water use efficiency, the Grass Patch trial again stood out, producing over 9 DSE per 100 mm of growing season rainfall. This not only reflects exceptional rainfall-to-feed conversion but also highlights the value of systems that respond well to seasonal opportunities.

Other trials, including Gibson, Condingup RM4, and RM4 + Dargo returned between 3 and 4 DSE/100 mm, indicating solid efficiency across more moderate rainfall conditions. By contrast, the Cascade Pasture Mix and Cascade RM4 vetch trials sat at the lower end of the spectrum, with rainfall use less effectively translated into grazing output.

These results reinforce the value of measuring both economic and resource efficiency when evaluating pasture systems. While biomass yield remains a helpful indicator, it is the cost per grazing day and grazing return per mm of rainfall that most directly influence profitability.

The standout performance of the Oats + Morava mix at Grass Patch highlights how well-matched pasture systems can deliver exceptional returns when grazing pressure, input efficiency, and pasture responsiveness align. On the other hand, higher-cost systems such as the multi-species mix may require refinement to ensure their inputs are delivering sufficient grazing return in real-world conditions.

Comparing pasture-based grazing to the cost of feeding pellets clearly demonstrates the economic leverage good pastures can provide. Even moderate-performing systems significantly undercut the cost of hand-feeding livestock, especially during tight seasons or in systems aiming to preserve capital.

Summary

Over a five-year period, the ASHEEP & BEEF Pasture Variety Trials PDS have delivered a significant study into the adaptability, productivity, and resilience of over 30 pasture varieties sown across the Esperance region. South Coastal Agencies (SCA), in collaboration with local sheep and cattle producers and supported by Meat & Livestock Australia (MLA), oversaw these trials across a variety of soil types, rainfall zones, and management systems. The trials were intentionally designed to begin with two years of plot-scale work, managed by South East Agronomy Research, to identify pasture varieties with potential for broader application. From years three to five, the focus shifted to commercial-scale broadacre paddocks, allowing for a more accurate assessment of those selected varieties under real-world grazing pressure and seasonal conditions.

The trials coincided with a period of extreme seasonal variability, from very wet years such as 2022 to one of the driest in recent memory in 2024. This unique timeframe provided the opportunity to evaluate both the risks and rewards of a wide range of pasture options in both favourable and highly adverse conditions.

Seasonal Context and Trial Methodology

Seasonal conditions varied dramatically over the course of the project. The 2022 season was marked by well-above-average rainfall, resulting in early breaks and strong biomass performance. In contrast, 2024 was one of the driest seasons recorded across much of the trial area, with delayed breaks, low rainfall totals, and limited follow-up moisture. Such variability enabled detailed evaluation of pasture establishment, persistence, and feed value under stress.

Each site was fitted with three grazing cages to simulate grazing pressure while enabling pasture cuts at 10, 16, and 20 weeks from the break of season. Samples were sent for biomass and nutritional analysis, with results used to calculate DSE (dry sheep equivalent) capacity, water use efficiency (WUE), and feed quality. Soil testing was also undertaken to assess constraints and inform nutrient programs. A strong emphasis was placed on understanding both above-ground performance and below-ground resilience, especially in relation to how pastures respond to moisture limitations and grazing intervals.

Root vs Shoot: Understanding Growth Dynamics

One of the key agronomic insights reinforced across the trial years was the contrasting growth habits between pasture species that prioritise early shoot growth versus those that favour root development. RM4 vetch consistently demonstrated a high root-to-shoot ratio, allocating early energy toward root establishment rather than canopy expansion. This trait proved particularly advantageous in seasons with limited early rainfall, as deeper root systems enabled the plant to access subsoil moisture during dry periods. In contrast, shallow-rooted species such as clovers and ryegrasses often allocated more energy to leaf development, making them more responsive to early showers but also more susceptible to false breaks and moisture stress.

This root vs shoot dynamic had clear implications for both establishment success and the timing of feed availability. RM4 vetch, though slower to produce early feed, emerged as a standout performer for total season biomass and persistence under dry conditions.

Pasture Wedge and Deferred Grazing

The trials reinforced the importance of establishing a strong pasture wedge—particularly in mixed farming systems where rotational grazing and feed budgeting are critical. Deferring grazing until a pasture has reached a minimum of 1000–1400 kg DM/ha proved essential to avoid uprooting plants and ensure rapid regrowth post-grazing. The “pluck test” was used to assess root anchorage, with stock only introduced once plants resisted pulling and leaf material broke cleanly. This simple test provided growers with an easy field-based method to ensure pastures had established well enough to withstand grazing without compromising regrowth potential.

In seasons with tight feed availability, early grazing of cereals such as Planet barley or Illabo wheat provided a valuable opportunity to defer grazing on slower-establishing pastures. Cereal crops were shown to deliver high ME and CP early in the season, allowing pasture paddocks time to build bulk and reach appropriate grazing thresholds.

Seed Set and Management in Aerial-Seeded Pastures

For pasture systems aiming to persist beyond a single season, careful management of seed set—particularly in aerial-seeded legumes such as vetch, balansa clover, and medic—was critical. In several trial paddocks, overgrazing during reproductive phases resulted in reduced seed production and diminished re-establishment in the following year. To mitigate this, stocking rates needed to be reduced or adjusted during flowering and seed fill to allow for adequate set. In some cases, pasture topping with a registered herbicide was employed to prevent weed seed set while freezing feed quality in place.

Cobra balansa clover, in particular, stood out for its dense seed production, short flowering window, and high hard-seed content, making it a reliable option for areas aiming for long-term self-regeneration. However, results showed that grazing pressure during reproductive stages must be closely managed to ensure persistence.

Varietal Performance: Risk and Reward

Across the three-year review period, RM4 vetch emerged as the most reliable and resilient variety, performing well in both high- and low-rainfall seasons. Its deep-rooted, drought-tolerant architecture allowed it to produce over 6,300 kg DM/ha in the dry 2024 season, while maintaining consistently high feed quality across all sampling intervals.

Diaman2ti bladder clover, while promising in structure and suited for regeneration in false break environments, struggled to establish under the dry early conditions of 2024. Once established, it produced good biomass; however, late-season weed competition and declining nutritional value reduced its overall impact. Its hard-seeded traits still hold potential for long-term systems, particularly when coupled with early weed control.

Ryegrasses, while beneficial for early feed under wet starts, underperformed in dry years. Tetila and Dargo ryegrass both failed to take advantage of their typical early growth advantage due to poor establishment conditions in 2024. However, their inclusion in mixes with slower-developing species like vetch proved to be a good risk management strategy in seasons with greater early rainfall.

Leafmore forage brassica demonstrated rapid early growth and good feed value when managed intensively. However, its high nutrient demand and susceptibility to insect damage late in the season limited its application as a stand-alone species in low-input systems.

The ASHEEP & BEEF Pasture Variety Trials commercial-scale demonstration sites, conducted from 2022 to 2024, have demonstrated the critical role of species selection, grazing management, and timing in determining pasture system performance. Resilient varieties like RM4 vetch have proven their worth in tough seasons, providing a combination of high feed value, nitrogen fixation, and biomass yield under limited moisture. At the same time, other species, such as Diaman2ti bladder clover and Balansa clover, have shown potential for regeneration and long-term persistence when properly managed.

The results underline the importance of matching pasture systems to rainfall zones, grazing expectations, and operational flexibility. Diverse pastures, carefully managed for seed set and grazing timing, provide a more robust feed base and can contribute significantly to whole-farm resilience. Future work should continue to refine these systems, particularly in light of increasing climate variability.