Sclerotinia Spraying: Ground vs. Aerial
All sclerotinia control products are registered for both ground and aerial application. Both methods have their positive and negative aspects. If a fungicide is needed, getting it applied at the right stage will be the most important consideration.
High clearance ground sprayer. In moist conditions, which are conducive to sclerotinia infection, the ground may be soft and sprayers will leave ruts. These ruts can slow the harvest process and be present in the field for years afterward. But if the aerial applicators are busy and can't get to your field in a timely fashion, ruts may be tolerable if it means getting the fungicide applied on time. Ground sprayers will also trample crop, but a 100-foot boom with 12" tires (times 2) equals only 2% trampling, or possibly less if the sprayer has crop dividers. Yield loss is not usually as high as the level of trampling. Yield loss from sprayer trampling should be less than 1 bu./ac. on a 50-bushel crop, which would be tolerable if the ground sprayer does the job on time and effectively.
Airplane: Spraying fungicide by air can be faster and more timely if the sprayer can't make it through the field because of soft conditions. If everyone is in the same situation, booking a plane to do the job at the correct stage may be a challenge. If you can get a plane booked, then a plane has its advantages: It doesn't leave ruts or trample crop, and it can do the job in conditions when a ground sprayer can't. Ensure the applicator uses the higher end of the range of water volumes recommended for aerial application to allow maximum coverage, especially for denser crop canopies.
Source: Canola Council of Canada