Populations of the highly competitive weed brome grass have been reported as spreading in western Victoria and now is the time for grain growers to be scouting crops to check for late germinations.
A new Agriculture Victoria factsheet has been released which details the ways in which growers can manage this challenging weed.
Speaking at Agriculture Victoria-led workshops in the Wimmera earlier this year (2020), Dr Sam Kleemann weeds scientist from Plant Science Consulting said some brome grass plants had evolved the ability to germinate later in the season, sidestepping farmers’ attempts to control them in autumn.
”If undetected, this late germination could quickly undo all the previous management and expenditure that growers put into controlling brome grass during autumn,” Dr Kleemann said.
“Brome grass is opportunistic. For example, if the weed seeds germinate in a crop in August and receive late spring or early summer rain, they can produce seed after harvest.”
Growers should be checking crops in spring for late brome grass germination and where possible, controlling the weed to prevent viable seed from forming.
“It only takes 100 plants per square metre to reduce wheat yields by 30 to 50 per cent,” he said.
Agriculture Victoria Land Management Extension Officer, Heather Drendel, observed a significant increase in the number of brome grass infested paddocks in the Wimmera in spring last year (2019).
“Farmers have difficulties controlling brome grass with pre-emergent herbicides last year (2019) due to seasonal conditions. Brome grass takes up to three years of concerted effort to control,” she said.
Western Victoria has the highest incidence of brome grass in south -eastern Australia and appears to be spreading into higher rainfall areas.It is predicted to cost growers in the Victorian Wimmera Mallee and neighbouring South Australian communities more than $11 million in reduced cereal yield, alone.
The new factsheet can be found at agriculture.vic.gov.au/managingbromegrass
Source: Agriculture Victoria