Brother-and-sister team, Paul and Karin Cluver of De Rust Estate near Elgin in the Western Cape, are renowned not only for top quality fruit and wine, but for a novel approach to production. Paul, who is managing director, and Karin, the production manager, utilise a range of the latest technological innovations on their farm, which consists of 140ha of apples and pears, and 80ha of vineyards.
Eye in the sky
Paul’s favourite gadget is his DJI Phantom 2 drone. While this model is not equipped with infrared imaging that allows advanced functions such as monitoring plant growth, it does allow Paul to survey inaccessible areas on the farm.
He recently used it to fly along the length of the power lines to identify damaged cables. Earlier this year, he used a drone to monitor the progress of a fire that broke out in the Elgin area, and evaluate the damage to De Rust Estate. Paul has also used a drone to establish the density of vegetation where invading alien plants are being cleared, and to monitor the mountain bike trails on the farm.
“In the past, farmers had to pay thousands of rands to get a plane up over their farm. Now they can use a drone at a fraction of the cost and obtain immediate feedback. As technology improves and becomes more affordable, more and more farmers will start using it,” he says.
While the drone is useful for a quick scan of farm activities, another technology – remote sensing – is better suited to monitor plant growth and identify problems. The Cluvers have used the Western Cape Department of Agriculture’s Fruitlook technology for this purpose.
“Fruitlook uses satellite imagery and gives producers weekly updates on various parameters, such as water use per hectare and plant stress,” says Karin.
This data allows farmers to identify problem areas and benchmark blocks against one another, as well as against blocks on other farms, enabling them to identify areas where they can improve production, she explains. Karin believes that Fruitlook will become even more important over the next few years, because from June this year, farmers will be required to declare their water usage as part of GlobalGap certification.
“Fruitlook helps farmers to keep records of exactly how much water they’re using in each block. With consumers becoming increasingly environmentally concerned, it will be a helpful tool to demonstrate that one is using water responsibly,” she explains.
The only disadvantage with Fruitlook, according to Karin, is that it does not work effectively in young orchards where the trees have small canopies and there is plenty of ground cover.
“Fruitlook can’t distinguish between the ground cover and trees. We had a couple of young orchards where the trees showed no water stress or deficit, according to Fruitlook data, but when we dug profile holes it was very clear the trees were suffering from stress,” she says.
Agrimotion undertook a pilot study with drones to pinpoint what had gone wrong. “Remote sensing with drones is done at a much higher resolution than with a satellite,” explains Karin. “So it provides a much clearer picture of what’s happening on the farm, especially in young orchards, with each tree represented by a single dot on the maps. Using drones confirmed our suspicion that the trees were under water stress and also showed which individual trees were affected.”
The farming team went out to investigate the problem areas and realised that the irrigation system was not working properly. New orchards were installed with hanging micro-sprinklers and not the traditional upright micro-sprinkler planted in the ground. This enabled the orchards to be weeded mechanically without damaging the irrigation system.
The problem, however, was that the area irrigated was smaller than with upright sprinklers. In fact, one of the production managers realised that sprinklers that covered the largest area when they were upright irrigated the smallest area when hung upside down. The sprinklers were therefore installed upright.
The Cluvers also used a drone to identify trees that were growing poorly due to a nutrient deficiency. Closer inspection revealed that the fertiliser spreader had been depositing the fertiliser against the ridge around the tree and not on top of it. Instead of adding a uniform amount of fertiliser to the entire orchard, the Cluvers use remote sensing to treat only the affected trees with slow-release nitrogen applied by hand.
Remote sensing, with soil evaluation, has also been used to identify the most suitable areas to place water probes. Water probes have to be placed correctly to provide a representative reading of the soil’s moisture levels, so that farmers can adjust irrigation accordingly. Remote sensing provides farmers with data on trees and soil at a specific time, allowing them to monitor the efficiency of their irrigation decisions and identify areas where improvements can be made.
Karin uses IRRICON’s irrigation scheduling system to manage irrigation. The programme uses G100 continuous logging probes to take water measurements at five depths in the soil. Readings are updated hourly, online.
“I can access the information via my cellphone in an orchard, and adjust the irrigation schedule via a computer or my cellphone from anywhere. The data is also colour-coded. So if I get a blue reading at the bottom of the probe, I know we’ve been over-irrigating and wasting water,” she explains.
A recent digital purchase on De Rust has been an ultra-wide band tracking device, Farmtrack, which monitors the tractors and other farm vehicles. Eighteen tractors are used for spraying the orchards and vineyards alone.
“[The system] shows us exactly where each tractor has been driving, allowing us to see when a tractor goes off course. For example, you can see whether a specific row had been skipped during pesticide application,” Karin explains. In addition, the programme indicates whether or not the tractors are driving at the right speed.
Using the programme over the past season has shed light on the efficiency of the systems on the farm. For example, Paul and Karin have learnt that turning circles in certain blocks are not always wide enough and the distances between lands and diesel filling stations are sometimes too far apart.
The idea behind the device is not to ‘police’ workers, but provide them with a tool for self-monitoring. Adjustments to the system, which will allow workers to monitor their driving speed themselves, are currently being tested. A red light indicates when the tractor is driving too fast, while a yellow light shows it is travelling at the correct speed.
Using Farmtrack has also made drivers extra-cautious about missing a row; they often physically check whether tractor tracks are visible in every row. Missing a single row could cause a pest or disease to spread to the entire farm, stresses Karin.
Farmtrack indicates the orchards that have and have not been sprayed, and provides data, such as the number of orchards sprayed by each driver, as well as the time taken to do so. The results are used to motivate workers, and the top three tractor drivers are recognised every month.
Karin’s favourite tool is the Keyphase harvesting programme, which creates a code for every fruit picked and packed on the farm and provides data on the quality of each batch in real time.
“In the past, it usually took about a day before we were able to document the quality and disease status of the fruit,” she explains. “Now we can track the volume of fruit picked per orchard and identify problems early. If fruit is bruised due to poor handling, we can talk to the pickers while they are still working to prevent any further damage. If we experience a lot of problems with certain diseases, we’ll make a note to take additional preventative measures the next season.”
Managers can access the data on their cellphones while working in the orchards. For Karin, the new digital technology offers many advantages, but three stand out: it is user-friendly, it provides real-time solutions, and it significantly reduces paperwork.
Email Karin Cluver at [email protected].