Plan Ahead for Tropical Perennial Grasses

AUSTRALIA - Now is a good time to start planning ahead if you’re considering sowing tropical perennial grasses to take advantage of their high summer growth potential, advises Meat and Livestock Australia.

22 March 2012

2 minute read

Oceania

Successfully integrating these pastures into your grazing system requires careful planning. Factor in issues such as sowing time, competition and varying management requirements that may arise when sowing mixtures of different species.

Up to two years ‘lead time’ is necessary to control summer-growing annual grasses. With some thought and planning this ‘lead time’ can be incorporated into a cropping or grazing programme, reducing the time that a paddock is out of production.

Interest in tropical perennial grasses in northern New South Wales has grown during the past 10 years, with an estimated 250,000 of tropical perennial grasses being sown in the past three year.

Inverell district agronomist, Bob McGufficke, said this has greatly improved the pasture feedbase in the area, providing increased options for producers during the warmer months.

"Tropical perennial grasses are drought tolerant and can produce up to 20t/ha of dry matter (DM) in a growing season (120kg DM/ha per day)," he wrote in a recent case study for Future Farm CRC.

"They also have a role in providing persistent perennial species in the landscape and year-round high levels of groundcover if well managed. Water use efficiencies are high compared with native perennial grasses. In trials in the Tamworth region, premier digit grass produced almost 30kg DM/ha for each millimetre of water used.

"Given adequate moisture, tropical perennial grasses respond to increased nitrogen and, as a rule of thumb, can produce an additional 100kg DM/ha in the growing season for every kg/ha of nitrogen applied.

"Due to their rapid growth, one of the biggest challenges is to maintain high feed quality. This can be achieved through good plant nutrition and appropriate grazing management strategies.

"Plant nutrition can be improved with fertiliser to raise soil phosphorus, sulphur and nitrogen to a productive level for tropical perennial grasses, and replace these nutrients (particularly nitrogen) when required. Well-managed legumes can also supply much of the nitrogen required by these grasses," he said.