FAST-GROWING perennial legumes are being touted as both a ideal feed option for drought-affected cattle producers in the north and a longer term solution to high stocking rates in the subtropics.
Leucaena has been shown to substantially improve profitability in grass-only production systems.
There is widespread evidence that beef cattle operators in Queensland are using stocking rates for perennial pastures that are substantially higher than recommended guidelines.
Research indicates these decisions are motivated by financial benefits.
A study looking at steer turnover enterprises using buffel grass pastures in the subtropics points to a large economic benefit from increasing grazing pressure, even with assumptions of declining land condition.
The Queensland Department of Agriculture and Fisheries work found profitability was very sensitive to grazing pressure.
Just a five per cent increase from 30 to 35pc pasture utilisation could generate $17,000 extra profit per annum, research scientist Dr Maree Bowen reported at a recent animal production conference at Wagga Wagga.
At the same time, society is placing considerable pressure on producers to reduce grazing pressure from beef cattle across Queensland’s pastoral lands.
Dr Bowen said the analysis demonstrated a large economic advantage from increasing grazing pressure above 30 per cent utilisation for buffel grass pastures, even with assumptions of declining land condition and animal performance.
For instance, producing slaughter steers under a 50pc pasture-utilisation regime with a continuous decline in land condition, and hence productivity, was $21 772 a year more profitable from the tenth year on than was a 30pc pasture utilisation strategy.
The latter is widely recommended as closer to a long-term, safe utilisation rate.
There was strong financial incentive to use high stocking rates over the medium term but very high grazing pressures where land condition decline resulted was unlikely to be sustainable in the long term, Dr Bowen said.
“Hence we need alternative strategies to improve profitability of beef businesses in regions such as Central Queensland,” she said.
“Other than phosphorus supplementation for breeders, the standout strategy is introducing perennial legumes into pastures.”
Planting sufficient leucaena to feed all steers from weaning to feed-on weights can generate up to $46,000 extra profit per year over 30 years, subsequent research found.
Purchasing additional breeders in order to utilise all the leucaena from day one further increases the profit.
“While perennial legumes are a potential solution to high stocking rates, there are potential negative consequences of implementing the system too quickly, such as increased financial risk and long payback periods, hence a staged investment process is recommended,” Dr Bowen said.
Drought fodder crop
Leucaena will take centre stage at a conference hosted by the University of Queensland at the end of October.
Associate Professor Max Shelton, from UQ’s School of Agriculture and Food Sciences, said leucaena legume offered a profitable and environmentally-sustainable option for cattle producers in dry, tropical regions.
“Leucaena addresses the main problem with achieving high quality range-fed beef in the tropics - it supplies high quality protein when cattle need it most - in the dry season, or during a drought such as we’re having now,” he said.
“There are substantial establishment costs, but it’s a profitable long-term investment with few risks, so in trying times like this, it’s an amazing fodder crop.”
Leucaena has been widely adopted in northern Australia and other tropical countries in the past 20 years, and has been the subject of considerable research.
This long-term data has helped address environmental concerns about the widespread use of the legume in farming.
“Many environmentalists view the legume as a potential weed threat, as there’s already a lot of weed leucaena along coastal Queensland,” Associate Professor Shelton said.
“The evidence shows that it didn’t come from graziers’ paddocks; nonetheless, this conference will reinforce farmers’ strategies to mitigate weed spread, including the promotion of a code of practice by landholders who’ve had extensive experience with leucaena.
“In fact, there are environmental benefits, as leucaena is very effective at reducing methane emissions and sequestering carbon.
“That’s just another reason why planting leucaena is the most productive, profitable and sustainable long term strategy for pasture improvement for the northern Australian beef industry.”