A type of adulticiding that leaves a residual to create a barrier is typically applied using:

The option selected focuses on the application of adulticiding in a way that leaves a residual barrier. Backpack misters are specifically designed to dispense insecticides in a manner that allows for the product to remain on surfaces for a given period. This residual effect is crucial for effectively controlling mosquito populations as it continues to protect the area even after the initial application. Backpack misters can target specific areas, ensuring that the insecticide coats surfaces where mosquitoes are likely to land, thereby creating a protective barrier.

In contrast, aerial methods cover a broader area quickly but may not always provide the necessary residual effect desired in certain environments. Thermal fogging is more suited for immediate knockdown of adult mosquitoes, as it generates a fog that disperses rapidly, but it does not enable the establishment of a long-lasting barrier. Handheld sprayers, while effective for localized applications, typically do not provide the same level of coverage or the ability to maintain a residual effect as efficiently as backpack misters do. This makes backpack misters the ideal choice for the scenario described.