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Strategic tillage serves a salvage purpose for northern growers

Strategic tillage can be an unpalatable pill to swallow for northern grain growers who have embraced the environmental and operational benefits of minimum and zero till systems over the past 20 years.

However, it is rapidly becoming growers’ best option in the battle to control weeds, renovate rough and eroded farmland and tram tracks, manage stubble load issues, effectively incorporate nutrients and control stubble borne diseases.

Many of these issues surfaced following the prolonged wet seasons during 2010-2012, forcing growers to consider undertaking strategic tillage as a ‘salvage operation’.

A recent survey of northern growers conducted as part of the Grains Research and Development Corporation (GRDC) funded Strategic Tillage Project found that most respondents who had used strategic tillage to manage an issue had been satisfied with the level of control achieved.

Tillage grdc

The survey found that growers had mixed opinions on how a strategic tillage affected the yield of the following crop with 43% being unsure or saw no change, 37% saying yield increased and 20% identifying a yield decrease.

The project surveyed growers across the northern region to assess the impacts of a strategic tillage on soil chemical, physical and biological properties and crop productivity, and how it could it be incorporated in a farming system with minimal cost and maximum benefit.

Project leader and senior soil scientist (soil and nutrient management) with the Department of Science, Information Technology, Innovations and the Arts (DSITIA) Dr Yash Dang said strategic tillage could be effective as a “salvage measure” to combat particular issues such as hard-to-control or resistant weeds, or rough country due to wet harvests.

“Our experience suggests that farmers are able to overcome challenging issues with the use of a single strategic tillage and then able to revert back to their more preferred farming methods,” Dr Dang said.

If considering introducing a strategic tillage into a minimum or zero tillage operation, Dr Dang said it was critical that growers consider the implications of reduced stubble load to the entire farming system.

“Minimum and zero till practices were adopted primarily to farm and store moisture but when that stubble is removed, the risk of moisture loss and erosion is much greater,” he said.

“Once the decision to cultivate has been made, key factors to consider are soil moisture status, ground cover, chance of heavy rainfall, next crop in rotation, chance of follow up rainfall, soil health and effectiveness of a previous cultivation.”

This media release and other media products from GRDC are available here.

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