69 - Barrier treatments methods for residential mosquito management revisited- the backpack fogger is obsolete

Mosquito management of individual properties by private pest control operators primarily entails monthly backpack fogger applications of a pyrethroid residual barrier treatment, often focusing on property line vegetation assumed to be utilized by adult mosquitoes as resting sites. An ideal backpack fogger delivers the product with an optimum mean droplet range of 60-220 microns for deposition on the top and underside of the leaf while ideally minimizing the potential for drift. The velocity of air required to shear the chemical droplet to an adequate size and propel the product to the intended deposition target thrusts a significant percentage of the treatment cloud to unintended sites. As a means of re-evaluating the delivery method for barrier treatments, over 200 residential mosquito service accounts were compared using the Stihl 200 backpack sprayer and the NPD Eliminator E-320 (18 volt) electric backpack sprayer. Assessment of droplet size, target deposition, non-target drift, time per service, volume of product used, cost of product, and re-service requests were undertaken. The NPD Eliminator proved superior or on par with the Stihl 200 fogger in every category. The extended wand and specialized application tip of the NPD system can be placed within the shrubbery canopy and other vegetation at multiple levels and angles. Concerns regarding drift and non-target harm are minimized as the application tip is near the target area. Calendar based scheduling of mosquito barrier applications, foregoing surveillance efforts, and utilizing a limited arsenal of treatment products with similar modes of action have the potential to increase pesticide resistance and is counter to best management practices. Alternative methods to backpack fogger applications for targeting mosquito populations are necessary to minimize repercussions to pollinators, protected species, and other non-target invertebrates, as well as elevating the standard of professionalism for pest control operators.