Winter Beef series: Is red clover silage a cost-saving option?

Rising fertiliser prices during the course of 2022 resulted in many beef farmers opting to try red clover swards as a means of producing cost-effective winter forage for the first time.

Red clover has the ability to fix in excess of 200kg/ha of nitrogen from the atmosphere annually.

Many beef farmers see red clover as a way of reducing their variable cost spend, while also potentially insulating their businesses from any further fertiliser price increases.

Cost benefit

In terms of cost, where red clover and perennial ryegrass swards (known as red clover swards) are managed under a three-cut system, the economic benefits in comparison to a typical two-cut perennial ryegrass only sward are about €3.30/bale in favour of the red clover sward, a modelling exercise conducted by Teagasc Grange has revealed.

The effect of fertiliser price was also examined, with the gap narrowing to €2.30/bale if a price reduction of 25% was witnessed.

Where better use of slurries produced on the farm are achieved and there is no need for the purchase of compound fertilisers, such as 0:7:30, this price difference stretches to €6.30/bale at modelled input costs.

This also takes into account that the slurry displaced from other areas of the farm may require some level of artificial fertiliser spend to counteract its use elsewhere.

In addition to the economic benefits, researchers at Teagasc Grange are aiming to establish the additional benefits from using a combination of clover and perennial ryegrasses as dedicated silage swards for beef enterprises.

Red clover yield

Due to the nature of the clover plant, and its upright growth habit, which often results in challenges in terms of persistency under grazing systems, a three-cut silage system is being examined as part of the research.

Red clover swards have been established over recent years and trials are currently ongoing to evaluate its performance as a winter feed source for dairy-beef weanlings and finishing animals.

Swards established in 2019 and 2020 Teagasc Grange produced dry matter yields of 19.3t/ha in 2022.

Previous research work has indicated that 15t/ha of dry matter annually are achievable over multiple years.

Red clover swards also have environmental benefits in terms of nitrogen fertiliser use efficiency.

These crops are not dependent on artificial nitrogen applications to produce a quality silage crop whereas perennial ryegrass only swards are.

Dr. Nicky Byrne

Along with this, researchers under the guidance of Dr. Nicky Byrne are also keen to examine the relationship between offering both dairy-beef weanlings and finishing stock red clover silage in terms of concentrate feed requirements, feed intake capacity, animal performance and carcass gain.

Dr. Nicky Byrne, the lead researcher on this project said: “Red clover has the potential to reduce fertiliser and feed inputs, yet can maintain or improve animal performance.

“When combined with a range of other management and animal breeding technologies, this can help boost the economic and environmental efficiency of dairy-beef systems.”

Grange silage test results

First-cut red clover silage was harvested in mid-May this year – a key timeframe for ensuring the production of a quality forage but also to allow light to reach the sward to optimise clover content in the subsequent second and third cuts.

This also served to create a sufficient time frame for the third cut to be completed by early September.

At the time of harvesting, the first-cut red clover sward had a clover content of 37% and was compared to the first-cut perennial ryegrass swards harvested on the research farm in terms of quality – albeit slightly lower in dry matter digestibility (DMD), as presented in table 1 below.

Table 1: Feed value of first and second cut silages harvested in Teagasc Grange as part of the clover study

Although the red clover silage had a lower crude protein content, this was attributed to the zero-nitrogen application, whereas the perennial ryegrass only silage had received 100units/ac of artificial nitrogen.

Red clover research

The aim of the study, which will see the research herd’s growing and finishing animals offered red clover or conventional silages ad-lib, is to establish how animals perform over the winter months and to examine the factors that result in animals performing better than would suggest from the crude feed values of the resulting silage.

Previous research activities have established that cattle offered red clover silages have a higher dry matter intake when compared to those offered grass-only silages, which resulted in additional weight gain over the winter period for weanlings and finishing steers.

It is hoped that the research work carried out at Teagasc Grange will identify the optimum management strategies to successfully grow stable yields of clover silage in Ireland.

If successful, the research could enable longer persistency of clover silage swards going forward, a challenge the crop has faced in uptake at farm level over the years, while also been beneficial in terms of diluting the costs associated with establishing the crop over a longer period of time.

In addition to this, it is hoped to further evaluate the factors influencing dry matter intake and animal performance potential.

One of the key areas the research trial is trying to evaluate is the protein quality available in red clover silages and what impact that has on animal performance and to see does the silage contain more protein which could be utilised for production in the animal.

Along with this, a focus will also be placed on the intakes of animals offered red clover silages, the level of animal performance obtainable and how efficient both weanlings and finishing stock convert either red clover in comparison to perennial ryegrass only swards in terms of liveweight and carcass gain.