Take Home Messages
- New forage cereal varieties are emerging with higher biomass potential for grazing by livestock.
- Choose forage cereal varieties to plant as a stand-alone crop or in a multispecies mix with traits that can fill feed gaps such as plant growth patterns, forage quality, disease resistance, and suitability for grazing, hay or silage, and grain.
Aim
To demonstrate biomass production of a selection of new and existing forage cereal varieties at different times of the year.
Background
Managing feed for livestock across a season can be a challenge. Feed gaps occur in summer and autumn when stubbles are exhausted and the new season is yet to break, or rains have come but pastures need to regenerate and establish. Another key feed gap period, particularly in lower rainfall dryland areas, is in late spring before harvest begins when pastures have reached peak biomass, are grazed and then turn off (Frischke and Jolly, 2020).
Having a blend of pasture species is useful to spread grazing windows for livestock across the season. A mix can offer more quality feed with high digestibility at different times, that encourages feed intake and supports livestock nutrition (Lifetimewool, 2006). Cereal crops can be a valuable part of the diet, providing quick early feed for stock in winter, particularly when the crop can establish early. Over the past decade, seed companies have expanded their range of forage cereal varieties beyond the traditional grain types for this reason.
Paddock Details
Location: Mitiamo
Crop year rainfall (Nov–Oct): 470mm (decile 7)
GSR (Apr–Oct): 182mm (decile 4)
Soil type: 0–70cm clay, 70–100cm silty clay loam
Paddock history: Oaten hay (2023)
Trial Details
Treatments: Barley, wheat and oat varieties, see Table 1
Target plant density: 180 plants/m²
Seeding equipment: Knife points, press wheels, 30cm row spacing
Sowing date: 24 May 2024
Trial average dry matter yield: 2.44t DM/ha
Trial Inputs
Fertiliser: Granulock® Supreme Z + Flutriafol (400mL/100kg) @ 60kg/ha at sowing
Trial managed as per best practice for herbicides, insecticides and fungicides.
Method
A field demonstration was sown using a completely randomised design, replicated four times. Biomass cuts of crop were sampled on 23 July (data not shown), and one replication sampled at peak biomass on 25 September. Normalised Difference Vegetative Index (NDVI) data was collected using a drone to estimate relative biomass on the same dates.
Results & Interpretation
The site received 27mm on 11 May which enabled crops to establish well. However, below-average rainfall and several frost events during flowering, coupled with heavy soil texture, limited crop growth and grass control, and as a result crops were terminated at the point of flowering.
Biomass was low across all varieties, averaging 0.25t dry matter (DM)/ha at eight weeks on 23 July and 2.44t DM/ha on 25 September.
Early season biomass was greatest for barley varieties Newton and Planet, and Alfresco wheat, followed closely by Kracken barley and Koala oats (Table 1).
The season limited plant growth, particularly of longer maturity varieties, such that production differences had waned by September, although production for Marleigh oats was slightly higher (but not significantly) (Table 1).
Commercial Practice and On Farm Profitability
Hand feeding of stock was required during 2024, extending through the winter when pasture feed was limited through much of Victoria and South Australia. Although the trial and farm biomass production were lower than average, it continued to accumulate later in the season making crops still useful for stock. In instances where the season compromised grain production crops were cut for hay where there was sufficient biomass or grazed.
When choosing cereal crops to grow for fodder, talk with other growers and seed sellers to understand growth and production traits, such as what time of year they produce biomass for grazing, their ability to recover from grazing, their potential to make quality hay, and the amount and quality of grain production. Also consider the disease and pest resistance profile to minimise management costs and maximise utility for cropping rotations. This will help decide which varieties to grow to fill feed gaps, and what should be included in a multispecies pasture mix.
Nutrition provided by cereal crops
Use feed tests to measure exactly what a crop is providing as it matures or be guided by data from previous trials (Frischke, 2023) and adjust for the season. In general:
- Young cereal crops at GS30 have approximately 1.5t/ha biomass, and high protein (20–30 per cent), energy (12–14MJ/kg), lower NDF (35–45 per cent) and high digestibility (>80 per cent)
- By flowering, GS65 and early grain fill, crop biomass can range from 4t/ha to 12t/ha, but quality falls to maintenance levels (hay quality) with lower protein (8–9.5 per cent) and energy (8–9.5MJ/kg), higher NDF (55–70 per cent) and lower digestibility (50–60 per cent).
- Declining quality and palatability limits how much livestock can consume. There will be enough crop nutrition to support dry ewes and wethers, but it won’t support the needs of growing lambs; supplementing with another source of protein and energy may be needed to meet any nutritional shortfalls during this time. An undersown legume pasture, a legume grain feeder, or access to an adjacent paddock with legume content can top up their high protein and energy needs.
- Once cereal grain has set, feed value rises again. The best feed value is the grain component, and to a lesser extent leaves and fine chaff. Grain has very good protein (11–15 per cent) and energy (12–14MJ/kg), low NDF (10–30 per cent) and high digestibility (70–95 per cent). As sheep eat the standing crop, they will consume enough fibre in chaff and leaves to meet fibre requirements
Livestock nutrition and health on cereal crops
To manage health of livestock grazing cereal crops:
- Cereals contain low calcium (Ca), sodium and magnesium (Mg) and high potassium (K). Supplement young cereal crops with a loose mix of limestone:salt:Causmag at 2:2:1. Note: Legumes increase Ca and Mg content of a mixed species forage, but not enough to counteract the effects of high K from cereal (Newell et. al., 2020), therefore cereal/legume pasture mixes should also be supplemented.
- Crops grazed from late booting to maturity don’t need magnesium. Instead use a loose mix of limestone:salt at 1:1.
- Stay up to date with vaccinations to prevent pulpy kidney resulting from high water-soluble carbohydrates.
- Although nitrate poisoning is rare, avoid it by introducing stock slowly, later in the day when they have full bellies (can be filled with hay), and delay grazing after nitrogen applications.
Other considerations are outlined in ‘Value of standing crops for lamb production and soil protection’ (Frischke and Jolly, 2020).
New forage cereal variety notes
New forage cereal varieties included in this demonstration (C. Altmann, pers. comm., March 2024 and AGF Seeds, 2024):
- Newton barley: a two-row, medium winter (between EGA Wedgetail and DS Bennett) feed-quality barley with awns that requires winter vernalisation (cold-period) to move from a vegetative to reproductive state. Its auricles and awns often have strong anthocyanin (purple colour) expression that persists through the seed coat of grain. Newton does not have high grain yield and is unlikely to develop grain in regions with warm winter temperatures. Early growth is prostrate, but it has very high tillering ability, meaning it’s a highly competitive plant type against weeds. Newton has improved disease resistance over Urambie. Newton will hang on for a long time during winter, then bulk-up quickly in favourable springs or with access to irrigation, resulting in high total biomass production.
- Alfresco wheat: a two-row awnless spring forage wheat with slow maturity, suitable for grazing, hay, or silage, and has purple grain. Alfresco is densely tillered, has excellent grazing recovery and improved lodging resistance over tall straw oats, and useful rust resistance, making it an alternative to forage oats.
- Marleigh oats: a mid-late spring forage oat, with excellent early vigour, fast biomass production, and sound recovery post grazing. Marleigh fills the autumn/ winter feed gap ahead of other winter cereals, can be sown in a mix, and should be grazed early. Marleigh stems bend, therefore, it is not suitable for hay.
- Kracken barley: a two-row awnless spring forage barley. Kracken is fast establishing autumn-winter fodder crop, superseding Moby with better disease resistance and biomass, and a slightly longer maturity. Sown from autumn to late winter for quick production, this variety can be grazed several times in a season and is suitable for hay. Can be used to provide weed control and soil preparation before renovating with perennial pasture. Note that early plantings are susceptible to heat stress which can lead to early grain development, so avoid sowing when soil temperature is greater than 22°C.
Growing and managing the grazing of high-quality forage, and providing supplements (grain or other quality feeds) to meet the protein and energy needs of reproducing and growing livestock, improves rumen efficiency and livestock production and can help to reduce methane emissions (Agriculture Victoria, 2024).
References
AGF Seeds. 2024, AGF Seeds Seed Guide – 2024. <https://agfseeds.com.au/wp-content/uploads/2024/05/AGF-Seedss-Seed-Guide-2024.pdf>
Agriculture Victoria, 2024, Livestock methane and nitrogen emissions. <https://agriculture.vic.gov.au/climate-and-weather/understanding-carbon-and-emissions/livestock-methane-and-nitrogenemissions>
Frischke A. and Jolly S., 2020, 2021 BCG Season Research Results, ‘Value of standing crops for lamb production and soil protection’, pp 162–168. <https://www.bcg.org.au/research-article/value-of-standing-crops-for-lamb-production-and-soil-protection/>
Frischke A., 2023, 2022 BCG Season Research Results, ‘Managing standing crops for production, livestock nutrition and soil cover’, pp 124–130. <https://www.bcg.org.au/research-article/managing-standing-crops-for-production-livestock-nutrition-and-soil-cover-2022/>
Lifetimewool, 2006, Pasture quality and quantity. http://www.lifetimewool.com.au/tools/pastures.html
Newell M., Holman B., Refshauge G., Shanley A., Hopkins, D., and Hayes C., 2020, Small Ruminant Research, ‘The effect of a perennial wheat and lucerne biculture diet on feed intake, growth rate and carcass characteristics of Australian lambs’, 192, pp 1–8. <https://www.sciencedirect.com/science/article/pii/S092144882030184X?via%3Dihub>
Acknowledgements
This demonstration received funding from the Australian Government’s Future Drought Fund.
BCG sincerely thanks Ash Gould for generously hosting the trial site at Mitiamo and for support throughout the project.
Thank you to Craig Altmann, AGF Seeds, for providing the demonstration seed and sharing insight about varieties.
