More lucerne increases production and profit

Including a higher proportion of lucerne in the system (40% compared to 20%) resulted in reduced supplementary feeding costs in drought years and higher lamb production and gross margins in years with a wet spring/summer. The benefit from lucerne depends on the degree of flexibility in the livestock system.

Main findings

Higher lamb production with more lucerne

• In the dry years experienced at Wagga Wagga EverGraze Proof Site, there was no difference in lamb production between systems with 20% compared to 40% of pastures sown to lucerne.  In wet spring/summers the system with 40% lucerne allowed lambs to be retained longer resulting in 168 kg/ha more lamb produced compared to the 20% lucerne.

Reduced supplementary feeding costs with more lucerne

• Supplementary feed costs were reduced in drought years in the 40% lucerne system compared to 20% lucerne.

Higher gross margins with more lucerne

• Gross margins were slightly higher in most drought years in the 40% lucerne treatment, but were significantly higher (by $264/ha) in the years with wet spring/summers as a result of higher lamb production compared to the 20% lucerne system in those years.

Flexible enterprises capture the benefits

• Flexible animal enterprises enable extra feed to be profitably captured and are necessary for opportunistic use of lucerne.

Read more about this research

The opportunity

The grazing areas east of Wagga Wagga with average annual rainfall above 600mm are able to sustain a number of perennial pasture species. Perennial grass pastures extend the growing season compared to annual pastures, but are largely dormant over summer. Summer active perennial species such as lucerne can provide quality feed during summer/autumn in suitable paddocks. The longer period of green feed, in comparison to annual pastures, allows the use of later-lambing enterprises and creates potential for higher profits by finishing lambs on summer active pastures rather than relying on expensive grain feeding. Use of appropriate perennial pastures is known to increase profitability, and by reducing potential groundwater recharge, also minimises the impacts of salinity.

While the area suitable for growing lucerne is often limited to 20% or less of the pasture base on properties on the southern slopes of NSW and north-east Victoria, there are some areas where a significant portion of the pasture base could be sown to lucerne. The development of summer active perennial species that are more widely adapted than lucerne may also present a future opportunity. While some studies (Byrne et al.) have found the optimal area of lucerne to be up to 30% of farm area on mixed farming properties, there is a lack of information for predominantly grazing properties.

What was done?

As part of a larger grazing experiment at the Wagga Wagga EverGraze Proof Site (located between Wagga Wagga and Tarcutta, NSW), two rates of lucerne were compared using a September-lambing sheep system in a replicated grazing experiment between 2006 and 2010. The lucerne experiment aimed to determine if there are any benefits of having more than 20% of the farm sown down to a summer-active species.

Low Lucerne (20%)

The pasture base consisted of 20% lucerne (cv. Aurora, dormancy 6), 60% phalaris (Australian) and 20% summer dormant tall fescue (cv. Resolute) and summer active tall fescue (cv. Quantum) mix Figure 1). All cultivars were sown with mid-season flowering (Riverina and Coolamon) and late season flowering (cv. Goulburn) sub clover cultivars.  Half of the ewes were joined to Merino and half to terminal rams allowing higher lamb production than a winter lambing, but retaining the ability to breed replacement ewes. The system aimed to sell lambs at weaning so only ewes are carried over summer. High lamb production is achieved through high numbers, not high individual lamb weights.  Benchmarking and modelling data indicate this should be a profitable enterprise.

High Lucerne (40%)

The same animal system as Low Lucerne but with a pasture base consisting of 40% of the farm area sown to lucerne, 45% phalaris and 15% to tall fescue (the same cultivars of all pasture species were used in both the High and Low lucerne systems).  The High Lucerne system may provide an opportunity for finishing lambs or provide better nutrition for ewes if seasonal conditions allow. This system holds the same advantages over winter lambing systems but the higher lucerne content is thought to lead to increased profits and reduce the risks associated with seasonal variability and failed springs. Both systems used the same stocking rate (dry sheep equivalents) in July (time of most limiting feed) to enable a fair comparison.

Because the field experiment was conducted under either drought (2006-2009) or extremely wet (2010) conditions, the performance of the two systems may not represent performance well in a more normal run of years. Simulation modelling using the GrassGro® decision support tool was conducted to allow comparison of the two treatments over a 40 year time period.

What was found

Seasonal conditions

Over the course of the experiment the site experienced a series of drought years followed by a very wet year (Figure 2). Full details of climate for the site can be found on the climate page. The combination of drought years followed by a wet summer provided a good opportunity to test the two systems at the extremes of the district climate with modelling used to provide a longer term outlook.

Higher summer and autumn grazing on lucerne during the drought

During the drought years (2006-2009), the annual *DSE grazing days per hectare between 20 and 40% treatments was similar.  However, the lucerne in both the High Lucerne and Low Lucerne treatment were grazed more during the summer and autumn months than the phalaris and tall fescue (Figure 3).

*DSE grazing days is measured by multiplying the number of days in the paddock x number of head x DSE rating per head divided by the number of hectares of each pasture species. Note the time spent in containment areas is not represented on this graph.

Low spring grazing and high summer grazing on lucerne in the wet spring/summer

During the wet spring/summer of 2010-11, lucerne was growing and held its quality through the spring and summer period.  Because lambs were weaned in December, grazing of lucerne in spring was limited to save pasture for weaned lambs, while ewes lambed on phalaris and spent some time on fescue pastures.  The wet summer then allowed the lucerne to be utilised to retain and finish lambs well into the summer period (Figure 4).

Higher production and profit from more lucerne

In dry years there was no penalty to lamb production by increasing lucerne from 20% to 40% of the pasture base. In a year with the wet summer the High Lucerne allowed lambs to be retained for 62 extra days (11 April versus 8 Feb), resulting in 85% higher lamb production in 2010 (Table 1).

There was no difference in wool production or wool quality (fibre diameter, staple strength) between the High Lucerne and Low Lucerne.

Supplementary feed costs were reduced in drought years in the High Lucerne system compared to the Low Lucerne (Table 1), resulting in slightly higher gross margins in the High Lucerne treatment in those years. This was mostly due to a higher average time stock were removed from plots and fed in autumn in the 20% treatment (21 days) compared to the 40% treatment (17 days).

The High Lucerne treatment was better able to respond to the wet summer of 2010 producing more lamb and resulting in a gross margin $264/ha higher than the Low Lucerne system (Table 1).

The proportion of lucerne alone did not maximise gross margins. The flexible animal enterprise enabled the extra feed to be profitably captured. Improved lucerne production over summer/autumn 2010 was matched with a sheep enterprise, which had the capacity to utilise the extra feed (high numbers of lambs to grow out) and flexibility in sale age of lambs. The weaning weight of lambs was usually the same in both lucerne systems.  The extra 168 kg/ha of lamb produced in 2010 was due to the extra feed allowing the choice to delay sale of lambs past the normal time for that system.  For further details on the performance of the sheep systems with different lambing times, see Flexibility in livestock enterprises is important for risk management in variable climates.

Table 1. Lamb production, feeding costs and gross margins on 20% and 40% lucerne systems at the Wagga Wagga EverGraze Proof Site.

Treatment	2006	2007	2008	2009	2010
	Live weight of lambs sold(kg/ha)
High Lucerne (40%)	170	157	168	211	365
Low Lucerne (20%)	168	144	165	198	197
	Supplement fed (kg/ha)
High Lucerne (40%)	1429	686	1118	1106	274
Low Lucerne (20%)	1517	742	1317	1125	274
	Gross margin ($/ha)
High Lucerne (40%)	23	118	37	145	567
Low Lucerne (20%)	29	88	24	108	303

Modelling the systems over 40 years

Modelling over 40 years showed using 40% rather than 20% lucerne, with the same sheep management, increased gross margins by 12% for a Merino ewe producing crossbred lambs in September. However, the benefit of extra lucerne relies on managing sheep to make use of the extra feed. Table 2 shows that altering the sale age of September born lambs from 14 to 23 weeks increased gross margins by $39/ha. This, in combination with increasing the proportion of lucerne from 20% to 40% of the pasture base, results in a gross margin improvement of $80/ha. However, there was considerable risk (range in gross margin) in doing this. This variation could be reduced by selling lambs earlier in years of low summer pasture growth to avoid feeding costs. The modelling also shows that better matching feed supply with livestock demand (July vs September lambing) improves mean gross margins.

Table 2.  The effect of lambing time, lamb sale age, and proportion lucerne on simulated gross margins of a Merino x terminal system (1970-2010)

Lambing	Jul	Sep	Sep	Sep
Lucerne (%)	20	20	20	40
Lamb sale age (weeks)	23	14	23	23
Mean Gross margin ($/ha)	236	304	343	384
Range in gross margin ($/ha)	462	646	739	799

Modelling of different management showed that the benefit of 40% rather than 20% lucerne was higher in purchased rather than self-replacing flocks (Table 3), due to a larger number of sale lambs. If lambs were only kept if live lucerne was available, there was a large benefit ($21 to $48/ha) from a larger area of lucerne. However, if lambs could be grazed on other pasture areas, there was little or no benefit of more than 20% lucerne.

Modelling of different proportions of lucerne showed most of the benefit of lucerne was achieved with only 10% lucerne area. Maximum gross margins were usually achieved with 20-30% lucerne, while a lucerne area of 70% or more reduced gross margins due to lower autumn and winter growth rates relative to phalaris, increasing supplementary feeding. Lucerne was more likely to increase gross margins if the livestock system used had the capacity to utilise pasture outside the growing season of phalaris. This means systems with more sale lambs, born later in the year so with a greater potential to increase sale weight.

Table 3. The effect of ewe purchase and lucerne as a lamb sale trigger on simulated gross margins (1971-2011) of a September lambing system producing Merino and crossbred lambs

		20% lucerne	40% lucerne
No live lucerne triggers lamb sale	Purchased	292	340
	Self – replacing	282	303
Lamb sale not triggered by lucerne	Purchased	353	367
	Self – replacing	314	311

Putting the research into practice

The place, purpose and management of lucerne

While the results show that increasing the area of lucerne in a spring lambing system can increase production and improve profits, the area of land suitable for growing lucerne may be limited on many properties, and its performance will also depend on site and location. Lucerne is best established in arable soils that are well drained and are not acid. The EverGraze Action – Growing and Using Lucerne provides further information on how to establish and manage lucerne.

A detailed summary of the different ways lucerne can be used, its management requirements and animal health management is also provided in the Hamilton EverGraze research message Lucerne reduces risk, provides options for livestock and prevents salinity. For information on making decisions for establishment of pastures, see the EverGraze Exchange – Selecting pastures for place and purpose.

Capturing the benefits of lucerne

In order to realise benefits from an increased area of lucerne, the animal enterprise must be able to economically capture this feed and convert it into saleable products. This may be achieved by a spring lambing system as used in this experiment or by other enterprises such as Split Lambing or trading livestock. Flexibility is a key aspect of the animal enterprise to enable good seasons to be captured profitably and risks in poor seasons managed.

Research at the Wagga Wagga Proof Site also showed that ovulation rate of ewes, and the resulting marking percentage could be increased by around 10% by flushing ewes on lucerne during joining. The More lambs from flushing on green feed page presents these results together with a decision tool for examining the benefits of grazing the lucerne to finish lambs, grow out weaners or flush ewes under different circumstances.  Also see the case study Lucerne leads to more legs on the ground[k31] , where Chris Shannon from Bookham describes how flushing ewes on lucerne increased lambing percentages by 30% on his farm.

The optimum proportion of lucerne will vary

The experimental and modelling results reflect the anticipated results for an increase of lucerne area from 20% to 40% of the pasture base with a spring lambing system.  Higher levels of lucerne may reduce winter stocking rate such that the overall impact is negative. This upper level will vary depending on the environment and the system being run.  Therefore, care should be taken when interpreting these results.

Farmer experiences

EverGraze case studies from the southern NSW, northeast Victoria and the upper southwest Victoria regions highlight that lucerne and other summer active perennials can be integrated into farm systems and utilised profitably for a variety of different purposes depending on the preferred livestock system, and the proportion of  the farm suited to lucerne.

Lucerne for environmental benefits and finishing lambs

At the Wagga Wagga Proof Site, host producer David Strong describes how he has integrated lucerne, eucalypt trees and fence-line plantings of shrubs into his system to significantly reduce groundwater recharge levels.  The lucerne is an important component of the system for finishing lambs in his fine wool Merino enterprise where he joins a portion of the ewes to terminal sires.

Analysing the benefits of lucerne in Ararat

At the Mooneys Gap EverGraze Supporting Site near Ararat in Victoria, Rod Vearing and the Perennial Pasture Systems group tested and modelled the value of lucerne and phalaris compared to a phalaris only system as part of an EverGraze Supporting Site.  In this case study, members of the group point out the value of lucerne for adding flexibility and/or filling a summer quality gap in their systems.  The role of lucerne on each farm varied depending on their system, and included finishing lambs, cutting silage, flushing ewes and keeping weaners alive over summer. At the Supporting Site, Rod had a June lambing time and was using a low winter activity lucerne.  The modelling showed that the benefit from lucerne is compromised by the need for winter feed.  Rod may have needed to consider changes to his system to realise the benefit of integrating lucerne.

Building flexibility into the system

In Holbrook, Vicky and Tony Geddes describe how they have used a range of practices to increase flexibility in their self-replacing Merino enterprise which they run at high stocking rates on phalaris-based pastures.  They are steadily increasing the proportion of the farm sown to lucerne to make up 10-15% of the total farm area. They believe the figures for lucerne stack up better than sowing brassica crops each year.  Cropping is also used to fill the autumn/winter feed gap and prepare paddocks for pasture establishment, and trade cattle are brought in and out of the system depending on seasonal conditions.

Managing with less area suitable to lucerne

Also at Holbrook, Chris Mirams discusses how the Woomargama Station enterprises are set up to take advantage of the small area suited to lucerne, but minimise the need for high quality pastures by running less growing stock through the summer period.

At Euroa, Andrew Walta discusses how on his land which has high aluminium levels, chicory is used in place of lucerne to provide quality feed for early weaned calves.

Managing ground cover with lucerne

At Cooma in NSW, Henry Bridgewater explains how straight lucerne stands present issues with ground cover in his environment.  To combat this, Henry has successfully established lucerne in mixes with perennial grasses.

What it all means

Where suitable areas exist, there is an opportunity to improve enterprise profitability by increasing the area of the pasture base sown to lucerne above 20% in environments similar to those found east of Wagga Wagga. Such a shift is shown in this experiment to provide improved profits in good seasons and similar returns in poor seasons. To best capture any pasture investment, the feed demand of the animal enterprise needs to be well matched to the pasture supply with sufficient flexibility to profitably capture additional summer feed grown in good seasons while also managing dry years. The development of new summer active perennial species with a similar growth pattern to lucerne but with a broader range of adaptability would be of significant benefit to the grazing industries. The Future Farm Industries CRC is investigating options for new perennial legumes, which may have potential for meeting these needs.

Acknowledgements

EverGraze is a Future Farm Industries CRC research and delivery partnership. The Wagga Wagga EverGraze Proof Site team was led by Dr. Michael Friend at Charles Sturt University.  An enthusiastic Regional Advisory Group consisting of farmers, consultants, extension officers and Catchment Management Authority staff provided significant input into the direction, management and interpretation of outcomes to make them relevant to farmers.

Authors and contributors

Dr Susan Robertson, Charles Sturt University, Wagga Wagga, NSW

Dr Michael Friend, Charles Sturt University, Wagga Wagga, NSW

Kate Sargeant, formerly Agriculture Victoria, Benalla