Which Sprayer Type Best Suits Your Requirements?

Method of application of crop protection chemicals has become a hot topic with the advent of drones and “smart” sprayers. So let’s look at some of the features of current spraying methods and where each might be used.

First, let’s look at the traditional or conventional method of spraying, which is using a standard ground-based sprayer with a boom that can be adjusted/fitted for such things as pressure, nozzle type, rate of application, and height above the ground. Some points to consider follow.

•   Essentially all crop producers have a standard sprayer that was obtained in the past.

•   A standard sprayer will likely be the best option for the application of a material such as a residual herbicide that will be broadcast with a large carrier volume–e.g. 10-20 gal/acre.

•   A standard sprayer that is on hand will certainly be the most economical machine to apply most products since it likely is already paid for.

•   A standard sprayer will likely apply the most total chemical in a season since all applications will be broadcast over the entire length of the spray boom.

•   Field topography should be considered since these sprayers will likely be affected by boom sway.

•   Traditional sprayers have the capability of applying larger volumes of material–i.e. chemical + carrier, which is usually water–which is often required and specified on the chemical label.

Second, consider spraying with a drone. Pertinent things to consider follow.

•   Using a drone to apply pesticides is a form of aerial application.

•   Since an application by drone will be done aerially, topography of the application site will be less of a concern than if using a ground-based sprayer with a boom.

•   Drone applications will be limited by the payload capacity of the drone and its recharging time.

•   Drone applications can be made when soil conditions are not conducive to applications by ground rigs.

•   Drones that are used to apply pesticides/herbicides can fly closer to the ground or crop canopy than an airplane, so materials applied by them should be less subject to drift away from the site of application.

•   Applying crop protection chemicals and herbicides by drones will likely be preferred if obstacles such as power lines, power poles, and trees at field edges will impede spraying by other methods.

•   Drones can be used to spray small irregularly shaped areas of a field to reduce overlap potential and to ensure that all portions of a site are treated the same.

•   Producers should check into using a drone service since purchasing a drone application device may not be cost effective if their use is limited.

•   Keep in mind that a drone device can be used for functions other than spraying, such as mapping of pest and weed problems in a field and detecting isolated problems within a field.

•   Drones are more maneuverable than a traditional airplane that is used for spraying.

•   Many labels for chemical products sold in the U.S. do not provide clear information related to drone spraying. For now, the US-EPA allows drone use for spraying if the pesticide is already labeled for aerial application and if US-FAA rules for drone operation are followed.

Third, consider applying materials with a “smart” sprayer. Pertinent points about using these machines follow.

•   “Smart” sprayers use a sensing device(s) [usually a camera or group of cameras] that detects the target pest or weed, and applies a material only where the pest or weed is found by the sensors.

•   It will likely be most economical to retrofit a standard sprayer with the additions that are required for it to become a “smart” sprayer rather than buying a new spraying machine that has “smart” spraying capability.

•   If retrofitting is chosen, the producer must ensure that the standard sprayer that is on hand and the particular “smart” package that is chosen are compatible.

•   Applying materials with a smart sprayer will likely result is less pesticide/herbicide being applied to a particular site since only infested areas will be sprayed.

•   The cost of applying a pesticide/herbicide with a “smart” sprayer will likely be lower since only areas with the targeted pest/weed will be sprayed.

•   Speed of application may be lower when using “smart” sprayers since speed of the machine will likely be dictated by the sensitivity of the sensors used to detect targeted pests/weeds.

•   “Smart” spraying of weeds will likely work best where a PRE herbicide was broadcast-applied or a cover crop was used to result in less weed pressure when POST applications are made.

•   Field topography should be considered since these sprayers will likely be affected by boom sway.

•   “Smart” sprayers will likely be the best method to use for targeted spraying.

•   Nozzle choice will likely influence the precision of spraying and thus its efficacy more with “smart” sprayers.

•   “Smart” spraying of pesticides/herbicides will become increasingly more important as agricultural technology evolves.

Of course, all of the above spraying methods have the potential for drift of spray material away from the site of application. If drift is a concern, consider a “smart” sprayer with a canopy.

The above discussion leads to the conclusion that each sprayer type has its strengths and weaknesses. Also, only individual producers can determine if the chosen spraying method is economical in their particular operation.

Click here for a White Paper that discusses “smart” spraying technology, along with links to various models of drones and “smart” sprayers that are presently available. Click here for an article that provides details about how/why precision spraying technology can be used to save time and money, and how machines with this capability may reduce the amount of pesticide/herbicide applied to a site.

Spraying technology is advancing at a rapid pace. This, plus the desire to reduce pesticide use in agriculture, means that crop producers must be ready and willing to upgrade spraying equipment when new technology is developed so that they can do their part in the drive for increased sustainability in agriculture production. Also, there needs to be more research that compares the effectiveness–e.g. overall spray coverage, control of targeted pests/weeds, penetration of sprays into a crop canopy–of pesticide/herbicide applications by drones vs. those made using traditional ground-based and airplane sprayers.

Composed by Larry G. Heatherly, Apr 2025, larryh91746@gmail.com