7.3 Selecting the Application Method: Broadcast, Band, Spot, Directed, Soil, Bait & Space Treatments

7.3 Selecting the Application Method: Broadcast, Band, Spot, Directed, Soil, Bait & Space Treatments

Utah's competency standard at R68-7-8(3)(g) requires an applicator to know the methods used to apply various forms and formulations, which method to use in a given situation, that fumigation, aerial application, sodium cyanide, or sodium fluoroacetate require additional certification, how method selection leads to proper use, unnecessary use, or misuse, and how method selection prevents drift and pesticide loss into the environment. The method is a decision in its own right — separate from the sprayer you happen to own.

1. Surface Application Methods

2. Soil Application Methods

• Surface applied — sprayed or spread on the soil, often requiring incorporation or activating rainfall or irrigation to move the product into the zone where it works.
• Soil incorporated — mechanically mixed into the soil, which reduces volatilization and photodegradation losses of certain herbicides.
• Soil injection — placed below the surface, common for fumigants and for systemic tree treatments.
• Soil drench — a large volume of dilute product poured or applied over the soil surface to saturate the root zone.
• Banded or in-furrow at planting — product placed with the seed or in the furrow.

Soil methods raise a specific Utah concern: products moved into the profile by irrigation on the coarse, low-organic-matter soils common in Utah's valleys have a shorter path to groundwater than the same product would have in a heavy-textured soil.

3. Enclosed-Space and Structural Methods

• Crack and crevice — a small amount of product placed directly into cracks, expansion joints, and voids where pests harbor. It puts the product where the pest lives and where people and pets cannot contact it, which is why it is the backbone of modern structural work.
• Void treatment — dust or aerosol injected into wall voids and similar concealed spaces.
• Spot treatment (structural) — limited surface areas, defined by the label, rather than broadcast surfaces.
• Perimeter / barrier — an exterior band around the foundation, subject to label limits on band width and impervious surfaces.
• Baiting — a food matrix carrying a small amount of active ingredient. Baits work when the pest is foraging and competing food sources are removed; sanitation is part of the treatment.
• Space / fog / aerosol — filling the air of an enclosed space with fine droplets. Good penetration of open space, no residual on protected surfaces, and high inhalation risk requiring evacuation and ventilation.
• Ultra-low volume (ULV) — very small volumes of concentrated product dispersed as extremely fine droplets, used in mosquito and stored-product programs. The tiny droplet size that makes ULV effective also makes it the most drift-prone method there is.

4. Methods That Require Additional Utah Certification

+-----------------------------------------------------------------------------+
|             METHODS GATED BEHIND ADDITIONAL UTAH CERTIFICATION              |
|                                                                             |
|  [FUMIGATION]        -> Category 13 (a Stored Commodities / b Structural /  |
|                         c Soil); plus the R68-7-18 minimum standards        |
|                                                                             |
|  [AERIAL]            -> Category 11 Aerial Application Pest Control, PLUS   |
|                         every other category for the intended application,  |
|                         PLUS a valid FAA commercial pilot license or        |
|                         equivalent remote pilot certification               |
|                                                                             |
|  [SODIUM CYANIDE /   -> Category 9 Regulatory Pest Control, limited to      |
|   SODIUM FLUOROACET.]   state and federal employees; expressly EXCLUDED     |
|                         from Category 12 Vertebrate Animal Pest Control     |
|                                                                             |
|  [CHEMIGATION]       -> Label-mandated safety devices; see Chapter 7        |
+-----------------------------------------------------------------------------+

Note that Utah's aerial category expressly covers airplane, drone, helicopter, or any other type of aircraft — a drone application is an aerial application and is certified as one.

5. How to Choose

1. Where is the pest? In the soil, on the foliage, in a wall void, in the air, in stored grain? The method must deliver product to that location.
2. What does the label authorize? The label names the permitted methods and often prohibits others. A method not permitted is not available regardless of how well it would work.
3. How much of the area is actually infested? Scattered infestations call for spot or band treatments; uniform pressure calls for broadcast.
4. What is downwind and downslope? Sensitive crops, homes, schools, apiaries, surface water, and habitat push the decision toward directed, band, spot, soil-incorporated, or bait methods and away from broadcast, space, and ULV.
5. What exposure does the method create for the applicator and for bystanders? Overhead and enclosed-space applications generally require more protective equipment; the label will say so.
6. Does the method change the math? Band and spot treatments do. Broadcast rates cannot be applied to a band without adjusting for the treated fraction of the area, and this is one of the most common calculation errors on the exam and in the field.

[!WARNING] Method selection is also an enforcement issue. Choosing an unnecessarily drift-prone method when a lower-risk one would work can produce a violation of R68-7-19(9) — applying pesticides when physical drift or volatilization may cause damage to adjacent land, humans, other species, or the environment — and of R68-7-20(21), which prohibits letting an application drift or run off from the target area whether or not damage occurred.