Weedwatch Tips to keep you parthenium-free

Parthenium weed rosette.

NSW graingrowers — and their Queensland counterparts so far problem-free — are being urged to be even more vigilant in the battle to control parthenium weed (Parthenium hysterophorus).

Recently completed research — supported by growers through the GRDC — indicates parthenium has the potential to become a major national problem for the grains industry. (See related story, right.)

First emerging as a serious weed in central Queensland, parthenium's spread into cropping areas has prompted a range of preventive measures, most notably cleaning of machinery at state borders.

John Fisher, NSW Agriculture's Program Manager Weeds, says while measures are well in place to contain parthenium's spread, ongoing grower vigilance is vital.

Mr Fisher says headers have been the most common source of on-farm infection with parthenium, but tighter border requirements for cleaning and inspections in the last two seasons have reduced the risk from them.

However, he says, it is critical for growers to know where harvesters, or other machinery moving onto their properties, have been and to insist — particularly if plant has come out of Queensland — on seeing the certificate of border inspection.

Other potential sources of parthenium infection are hay and other produce, seeds being found, for instance, in sunflower hulls brought in as stockfeed during drought. Buy certified seed or inquire and follow normal hygiene practices.

Growers should inquire as to the original source of hay and/or produce and, in any suspect cases, note where the material was fed out for later inspection.

As a notifiable noxious weed in NSW, parthenium outbreaks had to be brought to the attention of local weeds committees within three days of discovery. Local councils would provide advice and assistance with control.

"Parthenium can be controlled if people keep on the ball," Mr Fisher said. "But it sets seed so quickly — perhaps in less than three months — that inspections have to be frequent."

Program 3.3.1

Contact: Dr Steve Adkins 07 3365 2072

Region North