Case study: Ian Leulf– control of fleabane in a retained stubble system.
Property owners: Ian and Georgie Leulf.
Property size: 3600 ha
Enterprises: Wheat, barley and fat lambs.
Soil and pH: Sandy to clay loam with a pH of 4.9.
Overview:
The Leulfs run a controlled farming system as well breeding 900 cross-bred ewes. They follow a three year rotation of wheat, barley and fallow and have implemented a controlled traffic system for four years.
They try to keep the sheep off the stubble as much as possible and have separate cropping and livestock areas.
Fleabane control:
Fleabane first became an issue for the Leulfs in the summer of 2011. After harvest that year it was all through their cropping country and in Ian’s words, “it was big, it was ugly and it was difficult to control.”
The first year their control wasn’t great, being concerned with large amounts of double knock chemical on advice from agronomists. But by the second year a lot had been learned and they were much more successful in keeping on top of it, with in-crop management now manageable.
Cultivation wasn’t initially used to control the weed but rather to clean up paddocks during fallow in preparation for the following crop. However cultivation in conjunction with chemical application is now a tool used in the control of young fleabane.
However as Ian stresses, cultivation is not purely for fleabane control but rather as a part of their normal cropping program where new fallow is cultivated approximately once every six years.
Pre-emergent chemicals seem to be providing good control although there hasn’t been as wet a summer since 2010 to completely verify these results. If fleabane is present in emerging crops a double knock is applied as early as possible.
Avadex and Lontrel are two of the main chemicals Ian is using at this stage in fleabane control during the cropping season and during summer fallow control Glyphosate and Surpass are used.
Grazing:
Grazing is not an ultimate control method as livestock are not kept long enough on the paddocks for effective control; however they can be a useful too in cleaning up larger plants and removing stubble for easier sowing and better chemical application.
Key issues for fleabane control:
Be aware of any emerging problem early. Be prepared to control in-crop if necessary and use all tools available; chemical, cultivation and grazing.
Fleabane isn’t the concern it was back in 2011 as control of the weed is now more understood.