Ground Cover North : Ground Cover 049 April-May 2004 - North
High water-use farming systems – mopping up with perennials FEATURE / NEWS 29 APRIL 2004 MACHINERY & TECHNOLOGY By DAVID EAST On-farm ingenuity, rather than a big capital outlay, has been the key to Swan Reach growers Adrian and Colin Stoeckel switching to no-till cropping. The South Australian father and son team modifed their existing seeding equipment, which, according to Colin Stoeckel, did not require a lot of change. With their modifed seeder, the Stoeckels’ have virtually developed their own no-till (direct drill) system. The use of knife points and soil incorporated herbicides has allowed them to no-till their crops, plus improve their ability to manage a worsening brome grass problem. Adrian and Colin Stoeckel began no-till cropping on their 9300 hectares in SA’s Murray Mallee region in the 2002 drought year. “As it turned out, being a drought year, it was a pretty smart move in more ways than one,” Colin Stoeckel says. “It had a signifcant impact on protecting our farm from severe soil erosion.” Early in the season they bought a Horwood Bagshaw Scaribar and had it reconfgured for 300 millimetre (12 inch) row spacings. It was hooked up to a Horwood Bagshaw three-bin, 11 cubic-metre air cart equipped with electric drive and variable rate application Colin says modifying the seeding bar, which already had suffcient tine breakout and provided a choice of tine spacing options, was not a diffcult task. “When we decided to reconfgure it we settled on Primary Sales PR87 points and AIS fertiliser boots and our own made-up seeding boots. “We then thought about the pre- emergent weed control and couldn’t see why this had to be a second and/or separate operation. So we bought a Silvan Dosatron chemical injection unit and mounted it to the mainframe seeding bar, plumbed the machine with a row of spray jets across its full width and ftted a 3000 litre fresh water tank on the machine drawbar. “This tank is reflled from a nurse tank in about fve minutes, while we refll the seeder bin which takes about eight minutes.” Colin says both refll operations occurred simultaneously so there was no lost time. The improved brome grass control came from the direct injection system and narrow points. “Basically, our system gives us weed control and allows us to plant the seed in one pass,” he says. For the back of the machine, Colin says he and his father bought Manutec presswheels. “We made up our own carry frames for stagger attaching the wheels, one in front and one behind, to create what is essentially a walking presswheel arrangement. “Because our country comprises a fair amount of sand in some areas and stone in other places, we elected to take the seeding tubes off the tines and mount/attach them in front of the presswheels set-up. “With our seeding depth now controlled by the presswheels, we can till deep in the sandy soils and shallow in the stony country.” With the air cart and the spray system for the pre-emergent spray both being variable rate controlled (VRC), the Stoeckels are now able to make full use of the GPS guidance system they bought six years earlier. “This has proven to be a great asset in as much that we can accurately seed and spray chemicals at night as well as during the day, all in the one pass,” Colin says. Adrian and Colin Stoeckel pull their no-till seeding plant with a 300 kW Case-IH STX 450 tractor. They also have the option to use a stubble dumper behind their harvester for better weed control if necessary. “Our entire 2003 crop was sown with our no-till system, and while some of the wheat was affected by frost, we did have the best germination ever on our shallow stony country,” Colin says. Since converting to no-till using knife points, presswheels and direct injection herbicide application, in conjunction with their own particular on-farm modifed machine set- up, Adrian and Colin Stoeckel say they have achieved better crop germination and superior brome grass control, and introduced a greater versatility into their crop planting program, which has reduced their tractor hours dramatically. Colin Stoeckel said the change to no-till farming cost the family about $15,000. Coming out of a serious drought, there is an irony in the notion that our farming systems are unable to use all the available soil moisture. But it is the leakage of this surplus moisture into the groundwater system that contributes to Australia’s dryland salinity problems. A research project funded through the CRC for Plant-based Management of Dryland Salinity and the GRDC is exploring ways that perennials, capable of ‘mopping up’ surplus soil moisture, can be successfully introduced into annual cropping systems. The high water-use farming systems project is evaluating lucerne and other perennial pastures as productive components of crop and livestock systems. CRC researchers are conducting feld studies to determine the compatibility of perennials within both phase and inter-cropping systems (sometimes referred to as over-cropping or companion cropping) and simulation modelling to indicate where and how perennials might be successfully introduced into annual plant-based farming systems. Where conditions permit, the perennial of choice is often lucerne, with its ability to create a zone of dry soil below the normal rooting depth of annual crops. This acts as a buffer against water leakage from the soil to groundwater. Lucerne’s rapid and productive response to summer rainfall makes a further contribution towards maintaining that buffer. An option being explored by the CRC researchers, particularly for higher rainfall regions, involves direct drilling annual crops into existing lucerne (or other perennial pasture) stands. This inter-cropping takes advantage of the perennial’s ability to use out-of-season water, but without the costs and technical risks associated with removal and re-establishment of the perennial species. “This is still pioneering research for Australian conditions,” says project leader Mr Roy Latta, from the Department of Primary Industries Victoria, at Walpeup in the Victorian Mallee. “But already there are signs that inter-cropping could provide farmers with a tool for controlling leakage during the cropping phase, while at the same time offering the fexibility to move in or out of cropping or pasture. “The key challenge facing the research team is how to manage simultaneously two competing demands – the moisture needs of the crop to ensure maximum yield and that of the perennial species to ensure its survival. Farmers know that no season is ‘typical’, and they will not have the confdence to adopt a new system until they have seen it tested over several years against a range of climatic conditions.” The researchers have used the Agricultural Production System Simulator over 14 sites in southern and western Australia, for various inter-cropping management options. This CRC project involves collaboration with and support from CSIRO, Department of Primary Industries Victoria, NSW Agriculture, University of Adelaide and Department of Agriculture WA. For more information: Roy Latta, 03 5091 7246 email@example.com Making no-till a handy move Home-grown: Adrian and Colin Stoeckel have put a lot of development into their Horwood Bagshaw Scaribar no-till seeding system. Pioneer: Roy Latta checks progress of a feld trial. KEY POINTS OF RESEARCH SO FAR n Competition for water is signifcant, with wheat reaching only 65 percent of potential monoculture yields in wetter areas. n Lucerne production in inter-cropping varies between 65 and 80 percent of potential across the sites. n While at frst glance there might appear to be a yield penalty for the wheat crop following lucerne, there is an overall gain from the lucerne and wheat combined. n There appears to be value in suppression of lucerne to reduce its use of soil water before planting wheat. n Higher rates of nitrogen application in wetter regions increases the wheat yield. n It is important to capitalise on the ‘break of season’, as delays in sowing result in considerable wheat yield penalties.
Ground Cover 050 June-July 2004 - North
Ground Cover 048 February-March 2004 - North