Short-term ryegrasses have been an important source of winter feed for farmers for many years, particularly in the coastal and southern regions of Australia. However, some agronomists believe ryegrass is under-utilised in other areas.
Gavin Milne – a technical manager for S&W Seed Company Australia, has been conducting research and advising farmers and agronomists on the use of ryegrass in Australia for over 30 years.
“In the past few years we have tested the performance of short-term ryegrasses in non-traditional regions, and farmers are impressed with how they can boost winter carrying capacity and liveweight gain in cattle and sheep.
“Traditionally, farmers in regions like the southern downs of Queensland and slopes of NSW don’t plant a lot of ryegrass, generally relying on forage oats for winter production. One reason for this is that agronomists are aware that ryegrass is a temperate species that doesn’t grow or survive well in hot weather.
“Therefore, perennial ryegrass is not successful in these climates because plants die during the first summer. However, the temperate nature of annual ryegrass does not limit its use in hot climates because it is planted in autumn and thrives in the mild to warm temperatures over winter and spring.”
So what are the advantages of short-term ryegrasses? “Annual and Italian ryegrasses evolved in nature by setting seed in late spring before dying and then regenerating from that seed in autumn,” Mr Milne said.
“These ryegrasses developed vigorous winter growth so they could compete with other plants, set seed again and survive. Plant breeders have improved on this, creating varieties with even faster establishment and growth, and a range of dates when they set seed in spring.”
Mr Milne said farmers sow the ryegrass seed in autumn, start grazing in about 6–8 weeks, and can then graze every 3–4 weeks through winter and spring. This feed is very valuable on properties where most of the farm is usually covered in pastures that don’t grow well in winter and spring, including sub-tropical and unimproved pastures.
“The high feed value of ryegrass, with ideal levels of energy and protein for liveweight gain and milk production, is also a huge benefit. As a result of this technique, I’ve had many farmers tell me they are amazed with the amount of animal production they get from such a small establishment cost,” Mr Milne said.
“Annual ryegrass pastures die out naturally in spring, fitting into a pasture or cropping rotation with summer crops planted in spring or waiting for sub-tropical pastures to regenerate. Italian ryegrasses can keep growing through the first summer, but only in the cooler regions like the NSW tablelands, southern Victoria, and Tasmania. With good rainfall they can last for 2–3 years.
“Both species (Italian and annual) can also be made into hay or silage, providing high quality supplements in the bale or stack. Mixing with legumes and herbs can boost feed value and provide the nitrogen fixation benefits from the legumes.”
Due to the significant role of annual and Italian ryegrass in Australian grazing and hay farms, S&W Seed Company is dedicated developing improved varieties to suit the diverse requirements of farmers. This has led to three new varieties being released in recent years.
“Loader is a new tetraploid annual ryegrass, selected for high production over winter and spring to maximise the benefits each time farmers plant a pasture,” Mr Milne said.
“It also has a late heading date, allowing more flexibility for farmers in spring with feed quality being maintained longer. The plants are capable of longer growth, enabling farmers to take advantage of mid-spring rainfall.
“We are pleased with its performance as it’s not been beaten in any independent trials we have entered it in. Farmers have been impressed with the growth and animal performance, and the extended production in spring.”
Maheno Italian ryegrass, another new release from S&W, is a tetraploid variety with high dry matter production and a mid-heading date of +18 days.
S&W’s new diploid Italian ryegrass, Sorrento, displays high tiller density, allowing it to tolerate intense grazing and wet soil conditions.
With improved pasture density in spring, Sorrento can maximise production in spring and early summer in hot climates and come back strongly in the second year in regions with moderate summer stressors.
With the release of these three short term ryegrasses by S&W, agronomists can choose the ideal variety to meet the diverse needs of farmers and regions.
Mr Milne said these new varieties integrate seamlessly into farm systems that are experienced in using the species, but there are also opportunities to use them in non-traditional regions to boost production on beef, sheep, and hay production.
