January 2024’s crop protection column discussed how aerial drones were not yet approved for the application of crop protection products in agriculture. Spoiler alert – this has not changed as of May 2025.

However, it has not stopped a growing level of interest among farmers in using the technology. Our understanding of drone applications has also advanced considerably in the past 18 months. Crop protection products should start being authorized for drone application in the near future in Canada. So what’s changed?

For the last number of years, the Pest Management Regulatory Agency (PMRA) has maintained that application of crop protection products by drones represents new technology for aerial application and existing data and models based on conventional fixed-wing or rotary aircraft may not apply. The PMRA’s position is that the use of crop protection products with drones required specific assessments to understand aspects such as occupational exposure, crop residues, efficacy, and drift potential. The outcome of these are now becoming clearer.

Environmental risk assessments are a core part of the review framework for PMRA. This includes data on the non-target effects of products and where they may end up, such as the spray drift potential from applications. The latter is  only part of the environmental assessment where drones may be different than other foliar application methods using the same products. An international research collaboration has now determined that spray drift from drones is smaller and more similar to ground application equipment than other conventional aerial applications, which have larger spray drift potential.

The PMRA will now substitute a conventional helicopter drift model until a drone specific model is developed – which is conservative as it remains an overestimate of potential drift.

The two areas of interest on the human health side that PMRA has been investigating include the level of residues remaining in the crop after application and occupational exposures by workers using drones. For the first component, PMRA enlisted the help of Agriculture and Agri-Food Canada’s Pest Management Centre, which also is responsible for the minor use program familiar to fruit and vegetable growers. 

Four trials were done with both drones and conventional ground-based airblast or field sprayers in broccoli, peas, grapes, and apples using crop protection products registered on the crop. In each case, crop residues following application from drone-applied products were less than or equal to than those from the conventional ground application equipment. Based on this study, it is expected existing residue data from ground applications – which is commonly developed during registration – will fully substitute the need for any drone specific data. 

On the occupational exposure side, this includes information about workers handling drones during application and the mixing and loading of products. While drone-specific data on these items would be ideal and is under development, PMRA has been willing to substitute existing occupational exposure data from other application types. Further work is happening to confirm occupational exposure information this year.

Aside from PMRA, there has also been a limiting element at Transport Canada regarding flying drones over 25 kg in gross weight. As mentioned in the previous column, this required advance permission by requesting a Special Flight Operations Certificate (SFOC) in addition to the drone pilot certificate requirements. Finalized amendments to the Canadian Aviation Regulations have lifted this additional requirement as of November 2025 for drones under 150 kg in gross weight. Drones operating between 25 kg and 150 kg gross weight will now only require the Advanced Operations Pilot Certificate, easing regulations in this size range.

This becomes important when considering the trend in spray drone development over the past few years. Larger, heavier spray drones with higher capacity seems to be the clear trend in the industry now and this additional flexibility will help accommodate the bulk of the commercially available drones at this point. There are also some far larger spray drones being developed, but they would remain in the SFOC category currently.

A lot has changed since the last column on drone applications in January 2024. The first non-biological product has been approved by PMRA for drone application – Garlon XRT, a conventional herbicide used for vegetation control in non-crop areas. This joins the other biological products that are already registered for drone application by PMRA for mosquito control.

Compared to the United States, Canada is a long way behind on implementation. The U.S. Environmental Protection Agency has taken a stance on drone application of products and has cleared them for use provided the specific product already carries an aerial application label with conventional aircraft. This was something EPA staff mentioned they were proud of at last fall’s North American North American Trilateral Technical Working Group on Pesticides.

American growers are already successfully making drone applications with some of the same products available in Canada. The sky is not falling. Drones are providing a cost-effective application method and the ability to apply in conditions not suitable for other application equipment. There are many very promising comparisons showing drone-applied products can provide effective results.

The pieces are falling in place to finalize approval for drone application in Canada. We understand the environmental risks, have a good deal of information on the human health considerations, a pilot certification program that covers the typical size classes of spray drones and several years of commercial implementation south of the border. It’s time clear and practical drone spraying regulations are finalized in Canada. We know enough to get some rules in place to start allowing this practice more broadly.