Barley grass in a retained stubble system - farm demonstrations

The GRDC Stubble project aims to improve farm profitability while retaining stubble in farming systems on upper Eyre Peninsula (EP). Weed control in stubble retained systems is an issue with reduced herbicide efficacy due to higher stubble loads especially for pre-emergence herbicides. Current farming practices have also changed weed behaviour with later germinating barley grass genotypes now being present in many paddocks on Minnipa Agricultural Centre (MAC) (B Fleet, EPFS Summary 2011, p 177). As a part of the stubble project several MAC farm demonstrations were undertaken in 2014 to address barley grass weed issues including later germinating types and barley grass resistance to Group A herbicides within the farming system. An integrated approach to weed management aimed at lowering the weed seed bank can make use of diverse techniques such as cultivation, stubble burning, in-crop competition using higher sowing rates and possibly row orientation. The seed bank of crop weeds can be reduced within the break phase by hay making, or green or brown manuring. Other techniques used effectively in WA with ryegrass and wild radish have been narrow windrows and chaff carts, however little research has been done on the effectiveness of these approaches with barley grass because of its early shedding of seeds before harvest. Project: EPF00001 Maintaining profitability in retained stubble systems - upper Eyre Peninsula.