Aerial drones have become a more common sight on farms over the past few years for surveillance activities such as mapping and scouting to applying inputs such as fertilizer and seed. One area of great interest in agriculture has been the use of these vehicles to apply crop protection products.

Long in use in Asia, the idea of using remotely piloted aircraft systems (RPAS) – the government speak for aerial drones – for spraying crop protection products is relatively new in North America. The potential application of crop protection products with RPAS first caught the eye of the Pest Management Regulatory Agency (PMRA) in 2018. At that point it was decided that application of crop protection products by RPAS represents a new technology for aerial application and existing data and models based on conventional fixed-wing or rotary aircraft may not apply.

Based on that conclusion, PMRA took the position that the use of crop protection products with RPAS technology requires specific assessments to understand aspects such as occupational exposure, crop residues, efficacy and drift potential. For RPAS to be approved, it must be indicated on the product label as an allowable application method. So where does this issue stand in December 2023?

The PMRA has stated it has not received any data to support the use of RPAS for crop protection products that require a drone-specific risk assessment. Thus the hazards/risks posed to human health and the environment, or the value of the product, associated with the use of RPAS has not yet been characterized. Until this information is received and appropriately assessed, RPAS will not be included on a product label. In short, there are no crop protection products registered as of December 2023 with RPAS on the label and drone spraying remains illegal.

There are many efforts underway however in order to move forward with getting registrations for RPAS on the label. International working groups comprised of applicator groups, regulatory agencies, drone manufacturers and academics are conducting research to fill in the data gaps to better understand if and how specific risk assessments should be conducted for RPAS.

One such effort in 2023 was conducted by the Pest Management Centre of Agriculture and Agri-Food Canada to compare the residues from applications by RPAS with conventional ground-based airblast or field sprayers. Four trials were done in broccoli, peas, grapes, and apples using crop protection products registered on the crop. Samples were collected at harvest and will be assessed to determine if RPAS application results in similar residues on a crop compared to when the product is applied by ground equipment.

It is important to note that any trials that are currently using RPAS to apply crop protection products require specific approval from PMRA in the form of a research authorization. Many such trials were permitted by PMRA this past year.

Another less mentioned aspect of RPAS application is the Transport Canada requirements. These vehicles are considered aircraft in Canada and hence RPAS operators or pilots must also follow the Canadian Aviation Regulations. For most drones of interest in agriculture, a valid drone pilot certificate is needed for operation. There are two categories of drone pilot certificates basic and advanced. The differences largely relate to operations around people and near airports. The requirements include passing an online exam and also completing a flight review for the advanced certificate.

Even with a drone pilot certificate, there is also currently an additional step to fly RPAS over 25 kg gross weight. To operate these larger drones, an application needs to be made to Transport Canada for a Special Flight Operations Certificate (SFOC) which includes additional requirements such as a safety and emergency response plan. However, amendments to the Canadian Aviation Requirements were proposed in June 2023 to lift the SFOC requirement on RPAS up to 150 kg in weight. That would cover the majority of the RPAS technologies currently being touted for crop protection applications.

Finally, there is the education and training component for RPAS application that will be delivered by the provinces. In Ontario, for example, this is the role of the Ontario Pesticide Education Program (OPEP). The Grower Pesticide Safety Course delivered by OPEP is a requirement for farm users of crop protection products that needs to be renewed every five years. There are similar requirements in most provinces. It is anticipated that RPAS-specific training will be incorporated into these programs in the future.

Overall RPAS application of crop protection products is a rapidly evolving area. As with any new technology, the regulations are struggling to keep up with the pace of innovation. We have made significant progress towards better understanding how these application systems perform in the field. The technologies themselves are changing rapidly notably a trend towards larger capacity. One extreme example is the recent introduction of a commercial spraying RPAS with a liquid capacity exceeding 300 liters. It remains to be seen which format will ultimately be most successful for horticulture, a swarm of lightweight drones or a single high-capacity unit.

It is safe to say we are still some years away from having RPAS being an option for applying a wide range of crop protection products. Keep that in mind if you plan on drone shopping this winter.