Chipping away weeds

By Country News

A new mechanical weeding machine is quickly attracting keen interest from grain growers.

The prototype has been designed using a cultivator bar where tines are raised above the ground in a standby position, ready to chip the weeds out of the ground the moment they are detected with weed-sensing technology.

Funded in part by the Grains Research and Development Corporation, the groundbreaking technology will allow growers to control weeds in summer and winter fallows with greater flexibility for use in situations that restrict the use of herbicide application, such as wind, heat, surface temperature inversions and herbicide resistance.

‘‘Its ability to handle a vast range of weeds, at varying growth stages, is likely to reduce the number of ‘passes’ required to manage fallow weeds, compared with current herbicide practices,’’ University of Western Australia’s School of Engineering agricultural engineer Andrew Guzzomi said.

‘‘This will help to mitigate its slower travel speed and narrower coverage, when compared with spray equipment.

‘‘Another benefit is that the mechanical weeding machine’s periodic tilling action, that is appropriate for use in low-density weed population situations, will allow it to be coupled to low horsepower tractors.’’

Dr Guzzomi said the ‘‘rapid response’’ tine system was designed to chip out weeds at densities of one plant per 10 square metres, while travelling at 10 kilometres per hour.

University of Sydney director of weed research Michael Walsh said the machine had effectively killed summer and winter annual weeds that had been targeted in field testing, regardless of the growth stage of the weeds.

‘‘It is highly effective on both broadleaf and grass weeds, and soil disturbance is potentially low,’’ Dr Walsh said.

‘‘With a significantly reduced need for follow-up herbicide use, the system is an efficient tactic suitable for inclusion in an integrated weed management system.’’

The efficacy of the technology relies on accurate weed detection, with optical detection systems incorporated into the six-metre prototype before moving into commercialisation.