Ground Cover Supplement : GC Supplement - Grain and Graze
22 Fodders and mixed farming by chris guppy MANY GROWERS CHOOSE not to graze the fertile cracking clay soils of northern New South Wales due to concerns about the impact of livestock trampling on the soil. However, recent Grain & Graze research in the northern region shows that as long as at least two wetting/drying cycles are completed before sowing, swelling soils can self-repair to minimise subsequent grain yield loss. The results suggest damage from livestock trampling on cracking clays is not as high as first thought, with by david Watson WINTER CROP YIELDS following a lucerne phase are highest when the lucerne is completely removed in spring rather than autumn, according to Grain & Graze research in the high- rainfall zone of south-west Victoria. In total, 10 lucerne trials were carried out between 2010 and 2012 on a six-year- old stand of Grasslands Kaituna lucerne. Average lucerne plant densities were 47 plants per square metre, with the stand previously having been grazed and cut. The research tested a range of chemical and cultural options for removing the lucerne stand. Cultivation was ineffective as a means of lucerne removal. In a single-disc cultivation in mid-January, 99 per cent of plants survived, while 83 per cent survived the same treatment at the start of May. to shed light on the interactions between grazing damage and subsequent crop yield. Earlier research indicated that cattle grazing the cracking soils before sowing wheat resulted in compaction of the clods relative to the ungrazed control. But by the time of sowing, the wet summer had uniformly refilled the soil profile in both grazed and ungrazed plots. □ grdc research code dAQ00162 more information: Dr Chris Guppy, University of New England, 02 6773 3567, firstname.lastname@example.org CRACKING CLAYS SELF-REPAIR TO MINIMISE COMPACTION grain & graze 2 research indicates the impact of grazing fertile cracking clay soils on compaction and subsequent crop yields is not as high as first thought SPRING LUCERNE REMOVAL BEST FOR MAXIMUM YIELDS grain & graze research in the high-rainfall zone of south-west victoria has investigated the best methods and timing for lucerne removal and their impact on subsequent crop yields Up to 80 per cent of lucerne plants survived either a two or three- disc cultivation in mid-January. The most effective herbicide treatment was Grazon® Extra (triclopyr, picloram and aminopyralid) and glyphosate 450 applied in the spring, which removed 98 per cent of lucerne plants. However, Grazon® Extra has a four-month plant- back period for wheat, barley and canola. All other herbicide treatments using mixes of products available to growers failed to control lucerne effectively, even when combined with cultivation. Successful lucerne removal using herbicide requires: ¢ plants to be actively growing and translocating from shoot to roots at the time of herbicide application -- usually about two to three weeks after defoliation; the soils' self-mulching properties enabling repair of soil structure before planting of following crops. yields of grazed and ungrazed clay soil plots were similar, despite evidence of trampling damage in the soil post-grazing. The Grain & Graze research sought to investigate the effects of cattle trampling on subsequent grain yield on two four- hectare paddocks at the McMaster Research Station, Warialda, NSW. New techniques in cattle tracking and measurement of soil porosity were trialled TA BLE 1 Yield differences between spring and autumn lucerne removal at Inverleigh, Victoria. Treatment in trial at Inverleigh, Victoria 2011 barley yield (t/ha) 2012 canola yield (t/ha) Continuous crop 3.4 2.7 Spring 2010 removal of lucerne before 2011 crop 3.7 2.6 Autumn 2011 removal of lucerne before crop that year 2.7 2.9 SOURCE: DAVID WATSON AGVISE SERVICES PHOTO: DAVID WATSON Grain & Graze research in the high-rainfall zone of south-west Victoria has investigated the best methods and timing for lucerne removal and their impact on subsequent crop yields.
GC Supplement - Climate forecasting
GC Supplement - Managed environment facilities