Bird’s-eye view of Breezy Hill backs up PA
GroundCover™ Issue: 121 | Author: Rebecca Jennings
An unmanned aerial vehicle (UAV) has become an important tool in South Australian grower Joe Koch’s precision agriculture toolbox.
Joe, with his wife Jess and son Charlie, farm 1800 hectares at Booleroo Centre and Georgetown in partnership with his parents, Robert and Joyleen. Joe is the sixth generation to farm in the upper north of SA.
The family crops 1400ha with a rotation of wheat, barley, followed by peas, beans or canola. They graze 1100 Merino ewes on non-arable steeper country and on summer stubbles.
The home farm, ‘Breezy Hill’, sits just north of Goyder’s Line, where the 350 millimetres of annual rainfall lends itself to average district yields of 2 to 2.5 tonnes/ha for wheat and 1t/ha for canola.
The Kochs have developed a precision agriculture (PA) focus over the past six years, driven by Joe and Jess’s interest in how technology can lift productivity.
Joe was part of a group of proactive young growers who brought a real-time kinematic (RTK) base station to the local community in 2008 (the Mt Robert RTK Base Station Group now services 55 members across the Flinders Ranges), while Jess keeps a finger on the pulse of the industry in her role as a PA consultant at Pringles Crouch Agriculture, Crystal Brook.
The Kochs work with Jess’s father, Michael Wells of Precision Cropping Technologies, to interpret the data collected by a growing suite of PA tools.
They introduced autosteer technology in 2008 using the nearby RTK base station, which delivers two-centimetre accuracy (compared with 10cm accuracy from the previous satellite-subscribed signal). They started yield mapping in 2009 and added variable-rate (VR) technology in 2010. More recently, they developed electromagnetic (EM38) soil maps to zone cropping areas and are pH mapping both farms. The Kochs also access CropSpec normalised difference vegetation index (NDVI) images from their spreading contractor.
The Kochs integrate these maps to define production zones across the farm and target management. For example, Joe says there can be a 1.5 to 2.5t/ha drop in production on sandier areas of the farm, and pH is highly variable, ranging from 4 to 8.5 depending on soil type and topography.
“We were aware of differences in production but these tools finally allowed us to quantify this knowledge,” Joe explains. “The more data we collect, the clearer it becomes why different paddocks perform differently.”
The next step has been to drill down into different zones and take soil tests to quantify contributing factors so that the Kochs can target inputs rather than apply blanket rates.
“While our annual input bill hasn’t changed, we now have confidence we are targeting inputs,” Joe says. “For example, we used the EM38 maps to identify sandier patches across the farm and when we soil tested these areas it showed sulfur deficiency. So, we applied higher rates of urea/sulfate of ammonia to the sandier areas – 120 kilograms/ha compared with 60kg/ha on other areas.”
The Kochs are also planning a VR lime spreading and gypsum program this year.
The latest addition to Joe’s PA stable is a Phantom 2 quadcopter, which he purchased in early 2014 after seeing the potential of the technology in a friend’s vineyard, where aerial photos identified an irrigation breakdown.
“The UAV takes our PA maps to the next level, by providing a visual perspective on what is happening in the paddock. It allows us to identify relationships between photos and yield maps, and there are very clear correlations between what we see on the maps and from the air.”
Just as the soil tests allow Joe to ground-truth data from the PA maps, he says the aerial photos enable ‘air-truthing’.
“The UAV gives us the ability to identify factors that can’t be seen from the edges of a crop once it is established.”
While he says it did not take long to fill a hard drive with aerial photos, Joe has become more strategic in how he uses the UAV. He deploys it in paddocks, up to a height of 120 metres, four to five weeks after sowing and again before harvest.
Analysing aerial photos enables the Kochs to identity crop disease and populations of wild oats, track crop maturity, assess damage from stock, pinpoint old fencelines and soil variations, and monitor chaser bin compaction.
Joe has found the Phantom technology to be affordable, easy to deploy and “idiot-proof” with features such as a homing function when the battery is running low.
He plans to upgrade to a Phantom 3 this year. The new model will provide a live feed to his smartphone, features a camera that points directly down for enhanced visuals, and has capability to geo-reference photos so they can be ‘stitched’ together to create a more detailed perspective of a paddock.
Hand in hand with this new technology will be an interface with the gateway program that the family uses to integrate their yield maps. This will enhance the ability to overlay the aerial maps with the yield maps, soil tests, CropSpec NDVI and EM maps.
“The key to PA is to have a crack at it,” Joe says. “We just started VR on some trial strips in 2009, then did three paddocks in 2010 and moved up to VR inputs on one farm in 2010 as we built our confidence.
“It is also important to not just rely on the maps. Dig holes, soil test to see what is impacting yield variables, take a bird’s-eye view, and then you can look at strategies to lift lower-performing areas or target management to gain even more from productive areas.”
Joe has been involved with the Upper North Farming Systems grower group for the past five years – the past two as president – and enjoys this exposure to local research.
He points to a GRDC-funded water use efficiency project as driving a significant practice change in the district, with a nil-tolerance for summer weeds contributing to an additional 1.2t/ha on some farms.
Joe is also running his own on-farm trials, such as nitrogen strips, which can be mapped and tracked using his yield maps. He keeps an eye on local trials, and plans to swap LongReach ScoutA for LongReach TrojanA this year based on the latter variety’s performance in the National Variety Trials at Booleroo Centre.
The next step, Joe says, is to look into the economics of different rates applied to different production zones. The family also plans to pH-map the remainder of their Georgetown property.
The PA tools lay the foundation for controlled traffic, which Joe sees as being on the horizon for the business. He currently operates a completely unmatched system with a 9.8m Bourgault bar and box with knife points and press wheels, a 28m Hardi boomspray and a 12m New Holland CR9080 header, and would consider going to a 12m system with future machinery purchases.
More information:Joe and Jess Koch,