Application Procedures

Maggie Scarbrough

When it is time to decide on your application procedure, consider the effectiveness of the pesticide application, the possible effects on you and coworkers and the effects on other people and the environment.

Most aerosol and fogging applications are applied in enclosed spaces. If the space is not enclosed, you will sometimes have to make it an enclosed space. For this you would use tarps, plastic sheets and other chemical-resistant materials. Be sure the space is sealed well, possibly by tightening openings and covering the base securely.

Before using pesticides on a soil surface, you have to learn about the soil’s characteristics. Texture and the amount of organic matter will directly affect the pesticides ability to do its job. Organic matter can limit pesticide activity while soil with fine particles will require more pesticide.

Plant surfaces vary and the effect of the pesticide on it will vary accordingly. A waxy leaf with a cuticle layer will cause spray solutions to bead and run off. If the leaf has hairs, they will hold the pesticide and cause uneven distribution. Labeling will help you in these situations.

Wood, concrete and some fabrics are considered porous surfaces and easily absorb pesticides. If the goal is saturation, this works perfectly. If, however, you need pesticide to stay on the surface, more pesticide may be required. Nonporous surfaces have a tendency to cause pesticides to pool or run off.


For slanted surfaces or upright surfaces, it may be necessary to use stickers to aid the pesticide in clinging to the surface.

Labels will also give indications for porous and nonporous surfaces.

Another factor for a pesticide’s effectiveness is how clean the surface is. If it is particularly dirty, the pesticide may not even reach the surface.

Surface moisture is often ideal in aiding the spread of a pesticide. However, too much or too little surface moisture can also be a hindrance.

If the temperature is low, some pests may slow their activity and be more difficult to treat. Cold temperatures may also directly affect the pesticide’s action. Very warm temperatures can also affect a pesticide’s action by breaking down the chemicals before they have a chance to work. Labeling will give warnings for all of these circumstances.

Another consideration is that high temperatures combined with low humidity can increase the chances that the pesticide will evaporate. Again, labels will offer warnings regarding evaporation and the spread of pesticides. One way to help prevent a pesticide from moving off site is to increase droplet size.

Rain and irrigation can be a help when pesticides are applied to porous surfaces like soil. It is also helpful when water is needed to trigger the pesticide action as in the case of some granular pesticides. Labels will indicate if it is best to apply before or after watering.

Many times rain may be a hindrance to application as it can wash away and decrease the effectiveness of a pesticide. Before any outdoor applications, you should check the pesticide label as well as the forecast.

Air movement must always be considered, particularly for outdoor applications. Excessive wind will blow pesticides off site contributing to dangerous situations. Check labels for warnings. If you are indoors, ask to have ventilation altered to prevent such flow.

When it is time to schedule applications, always take in to consideration conditions that will affect the application. If you do not have a choice in scheduling, make the best possible decisions under the given circumstances. Many times scheduling applications for off hours is productive. Advantages include that there is less of a chance of other people being affected, it is usually cooler, wind is more likely to be low and there will be no direct sun in outdoor or glass-roofed sites.