As Published in ‘Grower’ Magazine February 2010.
Like many farmers who have adopted precision agriculture, Tim Macfarlane is using GPS to control his machinery. This gives savings in time, fuel, labour, machinery and other input costs.
Tim farms Holton Farm near Kaiapoi. He grows sweetcorn and pumpkin for the fresh market and seed crops including cabbage, clover, ryegrass and radish. Peas, wheat and barley are grown for feed.
The first steps into precision agriculture came to the farm in the 1990s. A hired hand-held GPS was used to map paddock boundaries. Knowing true paddock sizes allowed for accurate ordering of seed and chemicals.
Now, GPS guides the tractor providing for more efficient cultivation, planting, fertilising and inter row cultivation. It controls his spray boom too, switching nozzles on and off, section by section at exactly the right time. Spraying is more precise and less overlapping of herbicide applications reduces chemical waste and yield reduction.
Leica RTK GPS is now used for all high accuracy guidance, with corrections coming from an on-site base station. This gives season to season accuracy of better than 2 cm. Farm operations are routinely logged with GPS and transferred into an integrated farm mapping and management program.
New technology keeps coming to Holton
GPS and auto steering is allowing a shift towards Controlled Traffic Farming (CTF) which Tim thinks will increase yields by reducing overall compaction. CTF is also expected to provide other efficiencies. “As we grow in confidence with Precision Ag, endless possibilities are opening up to us,” says Tim.
GPS allows various types of captured data to be precisely located and mapped on the farm. EM38 soil conductivity sensing is being used to map relative water holding capacity across the farm. Greenseeker crop sensors are capturing differences in greenness across paddocks, helping decisions about weed control. Yield maps are clearly showing how much crop was harvested from each part of a paddock.
EM38 scanning and mapping was conducted in 2009. The intention is to gain understanding of soil depth, quality and water holding capacity. This information will be used to plan rotations and decide whether to irrigate more of the property.
EM38 mapping also helps determine location and depth of old, forgotten drains, identifying areas where inversion and ripping might be practical.
Weeds and technology
Weed challenges are now focusing Tim’s attention on GPS based weed management practices. These offer alternative options for control and can increase efficiency in the use of chemical, fuel and other inputs.
Tim wants systems that allow him to determine weed type and density using sensing and GPS mapping tools. Once the target is well understood, chemical rates and application methods can easily be varied. Already, GPS controlled boom switching is reducing overlap, providing accurate record keeping and proof of placement, and easy recording of chemical trial data.
When chemical tools are unavailable, the improved accuracy of RTK allows very efficient mechanical weeding. The accuracy lets Tim go later with the final inter row weeding pass and go closer to the planted crop. And RTK inter row weeding means less hand weeding in radish, sweetcorn, cabbage and pumpkin row crops.
The future of technology at Holton
Technology is giving gains at Holton. Tim says, “As we learn more about technology, we learn more about our farm and how we can keep making progress. Over time and with good planning, precision ag ensures that huge benefits are gained in production, efficiency and economics for the entire operation”
Tim is an agent for Leica Geosytems Precision Ag products, Raven GPS and spray control equipment, and Farm Data software. These technology products are integrated into the farming system. The GPS feeds operations and yield data into the farm software. Farm software feeds data and map files back to the GPS.
If you would like to keep making progress on your farm and to understand Precision Agriculture better, you may like to join LandWISE and to attend the LandWISE conference in Havelock North on May 12th and 13th. This year’s conference will be called ‘Know your farm – with Precision Ag’.
See www.landwise.org.nz for more information.