home news forum careers events suppliers solutions markets expos directories catalogs resources advertise contacts
 
Solution Page

Solutions
Solutions sources
Topics A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
  Species
 

Australia - Slow, hot burn will put heat on weed seeds


Australia
April 7, 2014

http://www.coxinall.com.au/wp-content/uploads/2014/04/Michael-Walsh_Slow-hot-burn-will-put-heat-on-weed-seeds.jpg
AHRI researcher Michael Walsh says windrow burning that sustains a ‘hot’ burn with temperatures exceeding 400oC is a key to achieving effective ryegrass and wild radish control.

Research conducted over several years has shown that 99 per cent of annual ryegrass and wild radish weed seeds are destroyed in effective narrow windrow burning.

Australian Herbicide Resistance Initiative (AHRI) researcher Michael Walsh said studies supported by the Grains Research and Development Corporation (GRDC) had shown that a sustained ‘hot’ burn where temperatures exceeded 400oC was a key to success.

Narrow windrow burning is conducted by farmers in autumn before seeding and involves burning 500mm to 600mm wide windrows of straw and chaff, in order to kill weed seeds.

Controlling weeds is a particularly big issue for Western Australian grain growers this year as seasonal conditions in 2013 have resulted in high weed seed burdens in many paddocks.

During harvest, up to 88 per cent of annual ryegrass seed production and almost all wild radish seed production (99 per cent) can be collected and placed in a narrow windrow.

In the following autumn, a successful windrow burn will destroy 99 per cent of these annual ryegrass and wild radish weed seeds.

Dr Walsh said burning during a light breeze could help achieve a slow fire which remained hot over a longer period of time and burnt the windrow right to the soil surface.

“The hotter and longer the burn, the greater the chance of getting a complete weed seed kill,” he said.

“Studies have shown that temperatures exceeding 400oC for at least 10 seconds will kill annual ryegrass seeds on the soil surface, and that wild radish seeds will be destroyed if this temperature is sustained for at least 30 seconds.

“We also have learnt that canola stubbles burn the hottest, followed by pulse and then cereal stubbles.

“In fact, canola and pulse stubbles are those you should focus on most when windrow burning – especially if you are implementing this practice for the first time – to achieve very good weed seed destruction.

“It’s a bonus if you can get narrow windrow burning to work effectively in cereal stubbles.”

Dr Walsh said burning canola and pulse narrow windrows was also easier and safer than burning cereal windrows.

“There is not a lot of crop material left outside canola and pulse windrows, so the fire risk associated with burning windrows in these crops is a lot lower when compared with cereals.”

GRDC ‘how to’ YouTube videos about windrow burning and other integrated weed management (IWM) practices are available at www.grdc.com.au/IWM-videos.

Multimedia resources about sustainable IWM practices are also available at www.ahri.uwa.edu.au and www.weedsmart.org.au.


More solutions from:
    . GRDC (Grains Research & Development Corporation)
    . Australian Herbicide Resistance Initiative (AHRI)


Website: http://www.grdc.com.au

Published: April 7, 2014


Copyright @ 1992-2024 SeedQuest - All rights reserved