Drones have come a long way in the last few years, with new models sporting improved cameras and sensors for navigation, allowing them to avoid obstacles.

Some drones come equipped with video goggles which give the operator direct control over the movement of the camera, enabling flights to be more immersive and informative.

These innovations open up new possibilities for farmers, especially when used as an inspection tool.

Drones have already proved useful for inspecting physical structures that are difficult to access, such as roofs of buildings, silos, solar panels and wind turbines.

However, the majority of ‘ready to fly’ drones are still designed primarily for taking video footage and are usually not made with agriculture specifically in mind.

Scotland’s Rural College (SRUC), in collaboration with SASA (Science & Advice for Scottish Agriculture), has been testing the ability of drones with these new capabilities to act as a tool allowing remote inspections of seed potato crops.

SASA trains and assesses plant health officials from the Scottish Government over a two-week period every year, to ensure their potato inspection skills are up-to-date. These officials then go on to perform multiple inspections of seed potato crops as part of the Seed Potato Classification Scheme (SPCS), checking each crop for diseases, viruses and rogue potatoes.

Following a demonstration of the equipment at SASA’s potato inspection plots at Gogarbank farm in Edinburgh in June, officials were given a chance to experience the visual feedback from a drone and provide feedback on how they believed drones could be used as part of the SPCS. Some of the officials also re-took the potato inspection exam, but from the perspective of the drone, rather than the traditional ground-based field walk.

This exercise revealed some of the shortcomings of this equipment with regards to verifying the type of disease or virus present. This included the imagery having too flat a colour profile or not offering the chance to see the crop in three dimensions, as well as the drone not being waterproof – something that is a key requirement for inspecting crops in Scotland.

However, it also highlighted the possibilities that this technology – with some improvements – could bring to crop inspections, by enabling the detection of diseases and allowing for faster and more targeted crop inspections in the future.

More recently, manufacturers have started to build drones specifically for agricultural use, with models from both DJI (the P4 Multispectral) and Parrot (the Bluegrass Fields) now on the market.

These drones come with integrated and calibrated multispectral cameras, enabling the real-time monitoring of crops using vegetation indexes such as NDVI (normalised difference vegetation index).

This means they will be useful for spotting variation across a crop and therefore creating prescription maps for variable rate applications, as well as for inspecting a crop for signs of disease.

The cost of these drones is much higher than ‘ready to fly’ drones – which may prove a barrier to their adoption until their potential is verified – but at least the mainstream drone manufacturers are starting to make integrated solutions with precision agriculture in mind.

Another area of cost in relation to drones is the new registration requirements that will come into force in the UK.

From November 2019 onwards, anyone intending to fly a drone weighing over 250gms will need to register with the Civil Aviation Authority (CAA) for a Flyer ID, and take an online theory test to ensure they understand the Drone Code and can fly with safety in mind.

Further to this, anyone owning a drone will need to register for an Operator ID, at an expected cost of £16.50 per year. Fines could be imposed on anyone who hasn’t registered, so for those who already own a drone, or are thinking of trying one out, it is important to check the CAA’s drone safe website (https://dronesafe.uk/) for the latest advice.