7.2 Application Methods & Placement

7.2 Application Methods & Placement

40 CFR 171.103(c)(7) requires practical knowledge of the methods used to apply various formulations, of which method to use in a given situation, of how method selection produces proper use versus unnecessary or ineffective use or misuse, and of prevention of drift and pesticide loss into the environment. It also requires you to know that fumigation, aerial application, sodium cyanide, and sodium fluoroacetate require additional certification - in Ohio, categories 2F/10C/6D for fumigation and Category 1 for aerial.

Outdoor and Agricultural Methods

Structural and Interior Methods

Placement definitions matter here because many food-handling and school labels limit which are permitted.

• Crack and crevice - a small amount of product placed directly into cracks, crevices, expansion joints, and voids where pests hide or enter. Typically permitted in food-handling establishments while in operation.
• Void treatment - dust or aerosol injected into wall voids, equipment voids, and hollow spaces.
• Spot treatment - a limited surface area, typically no more than about two square feet, treated where pests are found. Label definitions control.
• General surface / broadcast interior - broad application to floors, walls, or turf-like interior surfaces; often prohibited in food areas.
• Perimeter treatment - a band around the outside foundation and adjacent ground; many labels restrict the band width and the height on the structure.
• Baiting - stations or gel placements that pests carry back or feed on; the preferred method in schools while in session under OAC 901:5-11-15.
• Space treatment (fog, mist, ULV) - fine droplets dispersed into an enclosed airspace; requires vacating and ventilating.
• Termiticide trench and rod / sub-slab injection - the soil treatment behind a termite job, requiring the OAC 901:5-11-10(A)(3) footprint drawing before application.

Choosing the Method

Ask four questions:

1. Where is the pest? Root feeders need soil placement; wall-void ants need void treatment; canopy mites need coverage that reaches leaf undersides.
2. What does the label permit at this site? Method and site restrictions are directions for use, not suggestions.
3. What is the least-exposure option that still works? Ohio's IPM standard requires determining, with the customer, the most effective measures and methods that control the pest while minimizing exposure to humans, domestic animals, and the environment.
4. What does the method do to off-target loss? Air-blast and aerial applications release spray high and into moving air. Soil incorporation and bait placement release almost nothing to the air.

Method Changes the Math

This is where applicators most often go wrong. The label rate is normally expressed per treated acre. If you band a 15-inch strip over rows on 30-inch centers, you are treating half the field area, so:

$\text{Product per field acre} = \text{Broadcast rate} \times \frac{\text{Band width}}{\text{Row spacing}}$

A 2-pint-per-acre broadcast rate becomes 1 pint per field acre when banded at 15 inches on 30-inch rows - while the treated strip still receives the full 2-pint-per-treated-acre rate.

The same logic applies to spot treatment: a label rate stated per 1,000 square feet applies to the square footage actually treated, and applying full-area quantities to a partial area is an over-application and a violation.

Drift and Loss Prevention Built Into the Method

• Use the coarsest droplet spectrum that still gives acceptable coverage for the product and target.
• Keep the boom as low as correct overlap allows; boom height is the single largest ground-application drift variable after droplet size.
• Reduce pressure to shift droplets coarser with conventional tips, or use air-induction tips designed for coarse spectra.
• Use shields or hoods on directed applications near sensitive plants.
• Leave a downwind buffer whenever the label specifies one, and increase it beyond the minimum when a sensitive site sits downwind.
• Prefer soil-incorporated, in-furrow, bait, or void placements when they will do the job - drift you never create needs no mitigation.