THE jury is still out on whether a capital outlay of around $300 per hectare to establish leucaena on shallow forest country soil will be a long term winner but initial plantings have buoyed Stuart Barrett’s enthusiasm for further investment.
Thangool district cattle producer Stuart Barrett hosted a June 3 field day to review a Producer Demonstration Site (PDS) trial, co-funded by Meat and Livestock Australia and the Department of Employment, Economic Development and Innovation (DEEDI).
The trial investigated potential production benefits and the economics of deep-ripping forest loam and deep brigalow clay soils prior to planting leucaena-based pasture.
DEEDI senior pasture agronomist Stuart Buck and Fitzroy Basin Association field officer Joe O’Reagain co-ordinated the discussion and paddock trial inspection by 50 people.
Mr Barrett, a fifth generation cattle producer who has taken control of the family’s 6885ha breeding property, Drumburle and an 810ha brigalow country finishing block, Lawgi Station, is a firm advocate for pre-plant deep ripping to establish leucaena.
That was the catalyst for a PDS to investigate deep-ripped versus non-ripped leucaena plantings on the two soil types where plant establishment was compared and biomass growth was cut and assessed at six and 12-month intervals.
It was a trial supported by fellow members of the CQ BEEF Biloela Group, one of many nutrition, grazing, breeding and business management FutureBeef projects being co-ordinated state-wide to improve the profitability and sustainability of the Queensland beef industry.
Mr Barrett runs a 600 head Droughtmaster-base breeding herd turning off 18-24 month steer and heifer progeny to an established paddock sale clientele of grass finishers and feedlotters. The predominantly buffel grass pastures on the Lawgi Plateau holding also turn off about 100 head of steers for the premium export market.
A relatively new convert to leucaena, Mr Barrett said his primary management objective was to boost weaner liveweight gain by extending seasonal pasture nutrition well into autumn by providing access to high protein leucaena legume supplementation.
In the seven-month pre-plant preparations, Mr Barrett took advantage of Drumburle’s extensive machinery plant including a 5-tine Yeoman plough to cultivate 3m strips into existing pasture in July 2008.
With an objective to plant 1m twin rows at 6m centres, the strips were again cultivated with Yeoman sweeps followed by offset discs.
A boom spray application of 1.2 litres/ha of glyphosate and 0.4L/ha of 2,4D controlled grass and weed regrowth within the strips and the Barrett’s Caterpillar D5 equipped with two rippers put in the rip lines to 60-70cm deep in November.
In the non-ripped treatment, the strips were scarified and harrowed.
“For the late January 2009 planting operation, I hired a specialist disc-opener planter and chose to plant Cunningham variety leucaena at a rate of 3kg/ha,” Mr Barrett said.
A simple seed viability test showed 90 per cent germination and the scarified seed bought for $12/kg was treated with Lorsban powder for soil insect control.
For additional insect control, beetle bait (Lorsban/grain) was spread at 40kg/ha and glyphosate and Spinnaker herbicide was applied in a band over the row.
Soil moisture tests showed the ripped lines retained higher moisture than the non-ripped and plant emergence was 13 plants/m (ripped) to 10 plants/m (unripped).
Mr Barrett said severe May frosts followed by a prolonged dry winter-spring slowed the leucaena establishment.
“We probably had a 20pc plant loss to kangaroos, wallabies, rabbits and insects and endured a 15-month frustrating wait for the leucaena to reach 2m high before it could be lightly grazed,” he said.
Stuart Buck said the trial showed that the leucaena in the deep-ripped lines got away to a good start with biomass at six months recording 418kg dry matter (DM)/ha compared with 240kg DM for the un-ripped rows.
“It was interesting to note that at 12 months, the deep ripped plantings at 1090kg DM/ha had no advantage of the un-ripped leucaena that produced 956kg – a negligible 134kg/ha difference,” Mr Buck said.
“In the 80ha trial paddock at Drumburle where 16ha of leucaena was planted, it was lightly grazed in spring to encourage branching by stocking with 60 cows and calves for three weeks.
“That was followed up with another three weeks grazing in May using 300 weaners.”
Mr Barrett said the protein hungry weaners had cleaned up the leucaena leaf material and done well.
“There is still an excellent body of inter-row pasture in the paddock – mainly black spear, native blue grass interspersed with introduced buffel grass, Seca stylo and Siratro legumes.
“These improved pasture species were introduced 10 years ago when the paddocks were ripped with the Cat D5 fitted with a seed box,” Mr Barrett said.
“With conservative spelling and a build-up of soil nitrogen from the leucaena, I expect to achieve the industry forecast of 125kg of beef/ha which translates to upwards of $180/ha based on a $1.50/kg liveweight market.
“That will provide a return on investment after just two years for a pasture asset with a useful life expectancy of 30 years,” he said.
Mr Barrett said he would now continue his leucaena expansion program building on the 60ha established in the past three years.
“From the PDS leucaena establishment costs where ripping was $311/ha compared with non-ripping at $291/ha, I will maintain the practice of pre-plant ripping to give the leucaena a little more early vigour to sustain pest pressure and early frosts,” he said.
CQ BEEF Biloela Group is now planning an MLA-funded NLIS (National Livestock Identification System) open field day in mid-July to review a PDS trial using NLIS technology and associated equipment for herd data recording. This field day will be held at Gavin and Megan Muller’s property, Gavyna, Biloela.
Email a friend