As seen in Farm Weekly, 11/04/2024

Irwin Hunter & Co's annual Tetraploid and Diploid ryegrass varieties provide optimal production required throughout one growing season and can be used for grazing, silage or hay.

Tetraploid ryegrasses

IH Seeds leading Tetraploid varieties - Abundant; Amazon T; Astound.

Tetraploid ryegrasses are usually found to have dark green foliage and high water content, and they are considered to be very palatable pastures for livestock.

They tend to have larger and taller tillers, larger seed heads and wider, dark, rich green leaves.

This means they have a more reduced tiller density than the Diploid ryegrass cultivars.

As a result, they are very well-suited when mixed with clovers, as they provide a better opportunity for more clover establishment and, therefore, enhance the quality of the pasture, too.

With four sets of chromosomes, Tetraploid ryegrass has approximately double the carbohydrate, sugar, and water content than diploids and are suited to annual pasture systems.

The careful management of grazing and/or your cutting periods will influence production levels, and following with adequate nitrogen applications is important.

Tetraploids are suited to well-managed grazing, leaving a residual after grazing of 5-7cm in areas with moist or irrigated conditions.

Grazing rotations last 21-30 days, and sowing rates range between 25-35 kg/ha.

Abundant

Abundant is adaptable to seasonal growing conditions and variability.

It gives farmers confidence in good feed levels as it continues to produce high levels of foliage in the early establishment, rain permitting, through to the end of the growing season in mid-to-late spring, when other varieties may decline in feed value.

Abundant can produce higher levels of dry matter, an important index in Milk Production Potential (MMP).

Amazon T

Amazon T is well suited to Western Australian conditions and is best for areas with 450+ millimetres of rainfall.

Its recommended seeding rate is 25-35 kg/ha.

A fast emergence annual ryegrass with good rust resistance, producing much of its dry matter in winter/spring making it an ideal choice for double cropping with different summer crops.

Amazon T has a higher level of nutrient efficiency in poor soils and is more tolerable to higher temperatures due to higher levels of water-soluble carbohydrates, which help extend the ryegrass production season.

Diploid ryegrasses

IH Seeds leading Diploid varieties - Dargo; Safeguard; Finefeed.

Diploid ryegrasses tend to have more tillers per plant, generally with smaller and thinner leaves.

Although both Diploids and Tetraploids contain similar protein levels, they have lower water content per cell and a greater dry matter per kilogram of pasture than the tetraploid varieties.

Diploids are often considered more suitable on farms where overgrazing and pugging may occur during the year.

They can be grazed right back and recover quickly from hard grazing or in systems with higher stocking rates and are less likely to lodge when they grow over 15cm.

A diploid is a good choice for farms that focus less on a precise grazing management system.

Diploids are generally suited to drier, unpredictable seasonal conditions, shorter grazing intervals of 14-25 days, closer grazing (leave a residual of 2-5cm) and recommended sowing rates of 15-30kg/ha.

Dargo

Dargo is a consistent performer that can grow well in shorter growing seasons; Dargo is an annual ryegrass with high winter and early spring yields, has a good rust tolerance and is adaptable to a wide range of soils with rainfall of 400mm+.

It is very responsive to nitrogen applications, which should be applied with potash applications after the first and subsequent grazing where moisture allows.

Seeding rates range from 10kg/ha in 400mm rainfall areas to 25kg/ha in 550mm rainfall areas.

To improve tiller density, lightly graze at 6-8cm high or when grazing animals cannot easily pull the plant out.

It provides high-quality forage throughout the growing season and is suited to grazing, silage, and hay.

Safeguard

Safeguard is a variety known for its unique resistance against Annual Ryegrass Toxicity (ARGT) a toxic bacterium that infects ryegrass as pasture, hay or grain and affects livestock when consumed.

Safeguard should be sown before the break to align its flowering with Wimmera ryegrass.

This aids the plant's ability to cross-pollinate and produce seeds that are ARGT resistant, producing an ARGT resistant pasture the following year.

Combining the two

A mix of Tetraploid and Diploid ryegrass could achieve a more balanced pasture, retaining good dry matter production and an improved balance of quality feed.

Irwin Hunter & Co's Western Annual Mix combines Abundant and Dargo, providing the excellent attributes of both varieties, allowing it to be used for grazing, silage, and hay.

Contact your local farm supplier or Irwin Hunter & Co regarding their extensive range of pasture seed and mixes.