A NEW saline-resistant pasture grass could ease summer stock feed problems and improve saline-affected land.
Reclaimer and Gulf Cut are two varieties of Rhodes grass bred for high salt tolerance, aggressive growth and improved grazing and hay production characteristics.
Originally developed by Selected Seeds, Queensland, Reclaimer was commercially released in WA last week through specialist pasture seed distributor Irwin Hunter.
Derived from the finer-leafed and stemmed Finecut variety, the major selling variety in the Middle East, Reclaimer and Gulf Cut remained productive in salt-affected soils.
Irwin Hunter &?Co business development manager Ray Candy said Reclaimer Rhodes grass would be suitable for areas predominantly east and south of Perth affected by groundwater salinity.
Mr Candy said trials had shown it could grow using water with half the salt content of seawater.
"We have significantly increasing areas becoming affected by salinity through a combination of removal of vegetation for farming purposes and cropping," Mr Candy said.
"Rising water tables in some areas are also bringing the salt content closer to surface."
All Rhodes grasses are semi-tropical grasses suited to spring and summer growth and need moisture over that period for optimal production.
"In a lot of areas affected by salinity, there is a rising water table and as long as that moisture is within 300mm to 400mm of the surface, Rhodes grass should be able to tap into this moisture and provide some vegetative production over the summer months," Mr Candy said.
He said general WA rainfall patterns showed an increase in summer moisture north of Perth of about 20 per cent of the annual rainfall.
"South and east of Perth, it's only a minor proportion of their average summer rainfall, maybe only 10pc, but it's the rising water tables in saline-affected areas that gives it the potential to be sown."
Selected Seeds managing director Phil Smith said the new varieties' high stem to leaf ratio made them ideal for hay production as well grazing.
"We've had an increase in dry matter yield over Katambora of about 20pc," Mr Smith said.
"So it's a dual purpose option."
Mr Smith said the protein content of the grasses would depend on available nutrients in the soil.
Katambora is the most commonly used type of Rhodes grass with Finecut and Topcut the two pre-dominant field varieties.
Mr Candy said the sub-tropical perennial grass was ideally suited to a rotational program.
"It offers a summer forage option that isn't readily available through other temperate species and gives farmers more choice in stock management programs as it can support a higher level of livestock production over those summer months," Mr Candy said.
"Grazing Rhodes grass over the summer months would be more cost efficient compared to feeding imported hay."
Mr Candy said it was important not to overgraze the grass.
"Set stocking is not an option," Mr Candy said.
"We recommend farmers sow it, lock the gate and keep livestock away from it for between eight and 10 months until it's established," Mr Candy said.
"We say put the livestock in at 20 to 25cm high and let them graze it down to about 10cm before removing them so you're leaving bulk residue and not grazing the stolons or runners down."
As with any permanent pasture, Mr Candy said the grass should be allowed to achieve some natural seed drop.
If a lot of summer moisture prevented hay-making, Mr Candy recommended grazing livestock on it before it went to seed.
Mr Candy said because the grass grew quickly, was robust and fairly persistent, it could also be used to suppress problem species and help hold soils together over summer.
The grass could be a potential replacement for Katambora in Irwin Hunter's &?Co's Northern Perennial mixture, but in areas with salinity issues, Reclaimer and Gulf Cut could be used on its own or with Finecut.
The recommended application rate is 6kg/ha in a mixture.
Once the water table was lowered and humus built up from the grass, Mr Smith said alternate plant species may be able to be introduced to add value to grazing country.
He said there was no chance of the introduced grass becoming a weed.
"Because it's a summer grass as opposed to a winter one, it's unlikely it would ever become a problem, because we don't get enough rain," Mr Smith said.
"But if it did, it would be a very desirable weed."
Reclaimer and Gulf Cut have been gradually released in Queensland over the last 12 months.
In WA, on-farm demonstration plot trials have been carried out at Quairading and Moora over the last two years.
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