Article taken from Agronomist & Arable Farmer Magazine
Through its Plantsystems technology arm, Agrovista has been looking at crop sensing systems for four years. Lewis McKerrow, head of precision technology, comments on remote sensing.
Agrovista has been watching closely different technologies that can measure crop variation to make applications or record the data. We wanted to be able to offer a reliable service year in year out, something we felt was not possible with satellite imagery a few years ago.
Our early work on remote-sensing platforms was focused around tractor- or sprayer mounted sensors. Early experience came from looking at the Yara N-Sensor, although this soon moved onto the Fritzmeier Isaria due to the extra features it could offer over competitor sensors, such as yield potential maps. We are an agronomy advisory company first and foremost, but the landscape is changing. To be able to offer our customers industry-leading solutions we needed to be closely involved with precision-farming equipment so we could find out how to give the best advice to help growers get the most out of it agronomically. We now have enough trial information to confidently say the Isaria delivers 3-12% yield increase over flat-rate applications. Each season is different, and each field is different, which is why it is important we can apply technology to react to the variability we have. One of the trials this year involved a field of KWS Glacier winter barley. Like many farms we had a number of years’ yield data to show us a consistent pattern of yield variation. Most of this was down to soil type, with the variation more pronounced in wet seasons. Three nitrogen applications were made to the crop. The first was applied at 50kg/ha flat rate, the second was a varied ‘real-time’ application using the Isaria, resulting in an average rate of 90kg/ha, and the third was also varied using the Isaria, this time applying 40kg/ha on average. The grower contacted us to have a look at the resulting yield data as he had been very impressed at how even the crop appeared to be. The yield map revealed a very consistent yield across the field, with the crop averaging 9.5t/ha average (moisture corrected). Analysis of the data showed that in April there was a variation in the crop of 38%. By May, following the first variable application, this had reduced to 21%. The final yield showed it had fallen again, to just 16%.
Variation readings in a neighbouring field where a flat-rate nitrogen programme had been used showed levels of 34% in April, 28% in June, and 25% in final yield. The yield advantage using variable rate N was 9.4% in this trial, which at current market values equates to £82/ha in extra grain sales. With Isaria the best results come when making a ‘yield potential’ map for the field. This allows you to essentially create a map that tells the Isaria whether it is operating in a high, medium, or low yield potential area so that it doesn’t just look at the crop in isolation. In real terms this means that a thinner crop in a low yield potential area of the field will not receive as high a nitrogen rate as the same patch in a high yield area. Every time the Isaria passes through the crop it can be run in scan mode to collect biomass data from the crop. This can be really useful to form the basis of other inputs such as variable seed, the following year’s yield potential map, or even a yield forecast at flag leaf. For those growers who like the concept of remote sensors such as the Isaria but struggle to justify the investment, we have been working with unmanned aerial vehicles (UAVs) to be able to deliver reliable, high quality biomass maps on a pay-as-you-go basis. The advantage of using UAVs is that growers don’t have to make a big investment up front. However, it takes time to make a flight, process the data, and make prescription plans. Another advantage is that once the flight has been made the data can be run through a number of tools to give maps such as establishment, weed map, and % establishment to name but a few.
Plantsystems from Agrovista can now offer both of these platforms for the 2016 season. Isaria is sold and supported by a network of UK dealers which can be found at www.plantsystems.co.uk UAV flights can be booked through local Agrovista contacts. All the data can be uploaded to our new Axis MapIT Pro Advanced software or exported to selected farm management software.