FINDING a lucky four-leaf clover might not be so lucky for graziers using the old clover varieties – it might just be holding livestock back from reaching their full potential.
Some of the tried-and-true sub clover varieties have been about since the 1960s, but new research suggests graziers might be better off looking at modern pastures now on the market.
Evaluations from the National Annual Pasture Legume Improve-ment Program indicate some of the newer sub clovers have outperformed many of the traditional pasture stands such as Tikkala, Seaton Park, Woogenellup and Dalkeith.
Former NSW Department of Primary Industries (DPI) extension adviser Frank McRae said farmers and graziers wanting to provide high quality feed for their stock through winter and spring and rebuild hay and silage stores were advised to consider sub clovers such as Riverina, Coolamon, Izmir and Urana.
Mr McRae spent almost 30 years with the DPI before recently taking up a position as product development manager with AusWest Seeds in Forbes.
He recommended farmers and graziers placed as much importance on their pastures as their crops when it came to variety selection and paddock preparation.
“In cropping rotations a good sub clover based pasture is valuable because it produces feed and can be cut for hay or silage,” he said.
“Sub clover is also the ideal companion species with lucerne and a well grown pasture gives producers the option of extending the pasture phase before returning to cropping.
“Meanwhile, the pasture legumes are fixing nitrogen for the cropping phase.”
Mr McRae said the newer Coolamon sub clover was ideal for sowing with Riverina in hay or grazing pasture mixes.
Coolamon fits well into the southern slopes of NSW.
It’s a mid-season variety that takes about 140 days to mature at Wagga Wagga.
“Farmers love Woogenellup because it is upright and showy, but it is highly susceptible to clover scorch,” Mr McRae said.
However, he said Coolamon was a better option than the older Woogenellup sub clover because it had excellent resistance to clover scorch and produced 17 per cent more hard seed and 8pc more winter feed than Woogenellup.
“It also produced 22pc more spring feed than Seaton Park,” he said.
A short season variety which flowered within 110 days of sowing, such as Izmir, was an improved option in western areas such as Condobolin and Lake Cargelligo
“Suitable for 350 millimetres to 500mm rainfall zones, Izmir flowers early in the short growing season and produces high levels of hard seed so it persists better and provides a larger seed bank,” he said.
“Our trials showed Izmir gave 10pc more winter production and 7pc more spring production than Nungarin, providing extra feed when it was needed most.”
In a mixed pasture paddock the variety has performed well with a barrel medic.
Another early season variety, Urana, outperformed traditional varieties such as Seaton Park for hard seed production and Dalkeith for dry matter.
DPI trials found Urana produced 40 pc more hard seed than Seaton Park and had better resistance to redlegged earth mite to give better seedling growth.
“In the trials, the dry matter production from Urana was impressive compared with Dalkeith, so Urana is a good choice in a pasture mix for a wide range of cropping and pasture situations,” Mr McRae said.
Providing feed and seed at Forbes
Sown at the rate of five- to six-kilograms a hectare into a clean seedbed, a good sub clover-based pasture not only provides excellent feed for stock, but it will also set seed during the following three years as well as rebuilding soil nitrogen levels at a lower cost than fertiliser.
This is according to former NSW Department of Primary Industries extension adviser Frank McRae, Forbes.
“At these higher sowing rates, sub clover pasture costs about the same to establish as a single post-emergent herbicide spray,” he said.
Newer sub clover Riverina has been described as an excellent mid-season variety for a pasture mix suited to temperate irrigated areas, as well as rice growing and dryland regions.
“When you examine its performance in terms of disease resistance and dry matter production, Riverina is routinely under-estimated,” said Mr McRae (pictured).
An early to mid-season variety for higher rainfall or irrigated zones, in trials Riverina has proven to have the best combination of resistances to Phytophthora root rot, pythium and clover scorch – the three most common diseases in sub clovers.
He said a major improvement found in Riverina was its high level of resistance to the three known virulent strains of Phytophthora clandestine, which was considered to be the most serious disease of sub clover in irrigated pastures in south eastern Australia.
“Clover scorch is more prevalent in wetter springs in southern NSW and Riverina’s improved resistance to the eastern strain of scorch shines, compared with older, better-known varieties like Trikkala and Seaton Park,” Mr McRae said.
“Trials in southern NSW were conducted at Temora, Grogan, Quandialla and Yanco from 1983 to 1993 and chosen because they are commonly waterlogged in winter.”
Riverina also topped Trikkala and Gosse for hard seed levels and dry matter production, while it is equally suited to dryland or irrigated production across a wide range of different soil types.