MURRAY BRIDGE cereal and livestock farmer Michelle Thiele and her husband Kym have not seen broomrape on their property since it was found during a district-wide survey in 1998.
One hundred hectares of their land were quarantined after a total of 12 broomrape plants were found - parasitising cape weed - in two paddocks on their 2,630-hectare property.
Mrs Thiele believes the keys to preventing emergence of branched broomrape include growing crops that do not host the parasite and keeping broadleafed weeds, many of which are potential hosts, to an absolute minimum.
They have achieved this by switching from a crop- pasture rotation to continuous cereal cropping on their affected paddocks. They are also using more Group B herbicides because they will kill broomrape as well as controlling broad leafed weeds.
"We were heading towards continuous cropping. Discovery of broomrape just gave us another reason to do it," Mrs Thiele said. " However, the fact that broomrape has not emerged in our paddocks for four years indicates management tools are now available to counter the weed."
Conditions of quarantine
Farmers in the broomrape quarantine area can still sell grain, subject to conditions laid down in the Code of Practice for farming within the quarantine area.
The Code of Practice, which details procedures relating to all produce, machinery and livestock in the quarantine area, is designed to contain branched broom rape - the tirst step towards eradication of the parasite.
All grain paddocks in the quarantine area are physically inspected prior to harvest and grain can be moved out of infested paddocks or the quarantine area only with prior written authority from an authorised broomrape in spector.
Vehicles must be washed down and decontaminated before they can leave an infested paddock or the quarantine area. Grain from an infested paddock must be despatched directly to an end use that destroys broom rape seed.
Grain from crops in which the parasite is not found can be sold on the open market, subject to the movement protocols designed to prevent broom rape seed being spread in dust on vehicles.