Reining in FTR with cultivation and competition
Central Queensland farmer and grazier Rhys Daniels invokes the power of cultivation and crop competition against weeds like feathertop Rhodes grass in his family’s farming system.
Rhys and his parents Larry and Nancy, farm 2500 ha of alluvial black soils at Theresa Downs, north of Emerald on Queensland’s Central Highlands. About ten years ago, the Daniels family faced a severe blow-out in feathertop Rhodes (FTR) grass after spring rain caused a mass germination to flourish in sorghum stubble.
“The paddock was so bad that the new agronomist thought it was a pasture, not a cropping paddock!” says Rhys.“We knew we had to try something different, so we started with a series of knockdown products in the fallow. After the feathertop started to die, we went through with the multi-planter and pre-fertilised. That ripped up the grass, and we used a Gyral cultivator to plant wheat once the haloxyfop residues had degraded.”
Rhys finds chlorsulfuron provides useful long-term activity over their wide range of weeds in the wheat phase.
Having seen the benefit of full-disturbance planting, the Daniels have since made this standard practice for their wheat and mungbean crops. They also ramp up the crop competition using narrow rows (22 cm) in both these crops, which has resulted in excellent control of weeds across the farm. The cultivation also provides excellent seed to soil contact which promotes better establishment and a more consistent and even strike.
Like most others in the district, the Daniels embraced no-till farming in the 1990s and saw the benefits, so the decision to cultivate again was not taken lightly.
“Strategic use of cultivation has proven to be a very useful weed control tactic for us, and doing it at planting minimises the risk of erosion because we have cover growing again within ten days,” says Rhys. “We rarely have any establishment problems and usually see a benefit to the crop through mixing of stratified nutrients in the topsoil after several years of no-till.”
Generally, a paddock would only be cultivated once in four years or so, depending on the weed pressure. Since introducing this regime, the Daniels have not had a problem managing feathertop Rhodes grass. Their response to this difficult weed is an excellent example of the multi-pronged WeedSmart Big 6 approach having success in the field.
In the northern cropping region, researchers have observed FTR grass (Chloris virgata) germinating almost all year round, at temperatures ranging from 15/5° to 35/25°C (day/night temperatures).
Research has also shown that although burying the seed lengthens the period that the seed remains viable, if the seedbank is completely buried to a depth of 5 cm or more and left undisturbed for more than 18 months, strategic cultivation is an effective control tactic to rundown the FTR seed bank.
FTR is also known to be sensitive to crop competition so every effort that is made to grow a competitive crop, including cover cropping, will help manage the FTR seed bank.
Other resources
- Run down the summer grass seedbank in mungbeans
- What can I do to control large FTR grass in fallow
- Giving summer legumes the competitive edge
- FTR grass demands attention to stop seed set
- Creating stiff competition for summer weeds
- GRDC manual: Integrated weed control for feathertop Rhodes grass 2020 update
