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Picture better Black-grass control

NDVI imagery of Barton Black-grass application trials
New precision farming drone technology NDVI imagery of Syngenta Black-grass trials in Cambridgeshire have clearly revealed the differences in pre-em herbicide application techniques


Precision farming drone imaging technology gives an exciting and revealing new way to look a trials results, with the latest NDVI-style pictures from the Syngenta Barton Innovation Centre Black-grass Focus Site clearly showing the effects of different application techniques - and the benefits of #lowslowcovered

With forward speed, Syngenta Application Specialist, James Thomas, advocated operators should ideally work at 12 km/hr or less. That will immediately reduce turbulence behind the sprayer and minimise the movement of fine droplets; slower speeds also enhance all-round coverage of the soil surface. Furthermore, at slower operating speed boom stability is far better, enabling operators to maintain a constant nozzle height of 50 cm above the target.

What does that look like in practice? The NDVI picture (below) shows that applied at 16 km/hr the herbicide performance was significantly reduced. At 12 km/hr the results were far better and, whilst slowing down to 6 km/hr did further improve results, in practice 10 to 12 km/hr would give the optimum compromise between herbicide efficacy and sprayer output in the field.   

Barton NDVI application trial - forward speed

With water volume, James emphasised the importance of using sufficient spray to get the soil surface covered. In the past water volumes had been cut back to achieve more hectares sprayed per day, but that could have had a detrimental effect on weed control levels - particularly in increasingly diffiicult Black-grass control situations.

The imagery of the Barton trials site has shown that at a water volume of 50 or 100 l/ha the Black-grass control rates have been far less, compared to higher rates of 200 or 400 l/ha. In practice, he advocated that 200 l/ha is likely to give the optimum results in terms of timeliness of application and satisfaction with control rates achieved. James highlighted that other options to increase sprayer output, such as using water bowsers, water sources strategically placed around the farm and improved store management to achieve faster fill turnaround can also help increase sprayer output.

Barton NDVI application trial - water volume

Nozzle choice is another crucial element of getting the soil surface covered and minimising any risk of drift, James pointed out.

The drone imagery (below) has clearly shown that whilst the 3D Nozzle delivers outstanding results for Black-grass control, new designs of 90% Drift Reduction Nozzles achieved equally good control - with the benefit of operation in a wider range of conditions. These new nozzles should typically be the first choice for pre-em applications, he advocated - with the trial results so convincing that the nozzles are being offered at half-price to all growers for this season.


NVDI drone image for nozzle trials

James’ essential Rules for Pre-Emergence Herbicide Application are:

  • 50 cm maximum boom height
  • Less than 12 km/hr forward speed
  • 200 l/ha water volume
  • Use 90% drift reducing nozzles

You can review more of the Syngenta Innovation Centre Black-grass application trials by watching James' video tour here.