Beware the rising threat of Sterile Brome in cereal crops

Teagasc has said that Sterile Brome is becoming a particular problem in Irish cereal crops.

Control and management of the weed will require a combined reliance on integrated pest management (IPM) techniques and the targeted use of chemical treatments.

Ongoing trials at Teagasc indicate that herbicides, on their own, do not deliver the control of Sterile Brome that cereal growers would want.

“It’s a case of knowing the lifecycle of the weed,” said Teagasc’s Jimmy Staples.

Sterile Brome is a late summer / autumn germinating weed. So pushing back sowing dates would be strongly advised in fields where the weed is a problem.

“That targeted use of pre-emergent and post-emergent herbicides should then be considered.”

Winter wheat

Staples was speaking at this week’s Teagasc winter crops agronomy webinar.

Cork-based advisor Michael McCarthy also spoke at the event. Where winter wheat is concerned, he strongly advised that growers should walk crops now with a keen focus on identifying those weeds that are present.

He said:

There are plenty of herbicide control options that are available, when it comes to tackling broadleaf weeds, but the presence of Sterile Brome changes everything.

Recent Teagasc trials have confirmed that cocksfoot strips will stop the march of Sterile Brome in its tracks. Again, on the brighter side, ongoing trials at Teagasc Oak Park confirm that there are effective herbicide options now available when it comes to controlling wild oat.

The use of these products should be tailored to deal with the scale of the specific wild oat challenge that exists on individual farms.

According to Teagasc, Ireland’s winter wheat area has recovered with the acreage sown out last autumn back to what would be considered normal levels.

But the difficult planting conditions that did prevail have led to many crops losing a lot of vigour over the following months.

Thin crops

How to best manage these thin crops was a topic discussed in some detail at the webinar.

Kildare-based advisor Ivan Whitten stressed the benefits of providing the newly-germinating plants with sufficient P in order to stimulate strong root growth.

“There was also an issue last year with a lack of vigour in some of the seed planted out. This could have been accounted for by the very wet conditions that prevailed during the previous harvest,” he said.

“Pest issues post-establishment were also an issue.”

Looking ahead, Whitten said that thin crops of wheat must be encouraged to tiller in order to maximise their yield potential.

This can be achieved by the split application of a growth regulator in tandem with a suitably tailored fertiliser programme.

He cited the application of two bags of 11:7:25 per acre in mid-February, followed by the same again at the beginning of March. The use of a compound fertiliser in this way will encourage root and general plant growth.