Carrots cannot even be used for processing as all the sugars have been stripped by the parasite and they are fit only for stock fodder. Broomrape seeds are small, like dust, and last for many years in the soil. A single Orobanche plant can produce up to 500,000 seeds, with dormancy of 10 years or more being common. Once they have flowered, broomrapes will produce seeds even after they have been pulled out. Control The only way to control pest broomrapes is soil fumigation with methyl bromide being the most effective.
Some herbicides control pest broomrapes but they develop herbicide resistance.
They have also overcome Orobanche resistance bred into crops. For severe infestations the only viable option may be to switch to non-host crops such as orchard crops or vines. All Orobanche are AQIS prohibited imports but the seeds could enter the country undetected. The seeds can be spread by contaminated soil, produce, machinery, livestock or clothing. If these parasites become established, even in small areas, all Australian export markets could be affected as many of our trading partners prohibit all Orobanche .