Jun 28, 2011 – If You Can’t Take The Heat……


With the intense heat of Las Vegas what would be the best outdoor perimeter preventive chemical for treatment of homes? Which would last longer? I use products such as Suspend, Demand, Cy-Kick, and Cynoff. Should I be switching to wettable powders in the summer months?


Heat definitely is one of the enemies of pesticide active ingredients, and hot surfaces or ambient temperatures can be expected to severely shorten the effective residual length of our insecticides. All of the products you list are Synthetic Pyrethroids, which may be more stable under environmental stresses than were the old Organophosphates and Carbamates, but still would be sensitive to extremes.

I personally believe that microencapsulated formulations such as the Demand and Cy-Kick would last longer than other formulations. The microscopic and porous capsules keep the active ingredient in them for a more controlled "release", and to some extent protect it from degradation. These and the wettable powders also may tend to attach to passing arthropods far more easily than do the suspended or emulsifiable concentrates, where a thin film of the active ingredient remains on the treated surface after the water dries away. In Las Vegas in July that probably takes about 3 seconds for the water to evaporate. I'm not convinced that any one active ingredient necessarily works better overall on occasional invaders than any other, so you often can find a product name brand in a WP that may currently be in a different formulation.

Since your quest is for products effective as a perimeter treatment to intercept bugs before they manage to get inside a WP or ME sounds like the more logical choices. Since they end up as tiny particles resting on the treated surface the passing bug will acquire some of the particles as it walks over them, and now with the a.i. attached to them they can acquire the lethal dose in a leisurely manner. With the other formulations the insect needs to actually rest on that treated surface long enough to absorb the lethal dose, and this may take awhile. For the old OP's it often was 30 to 60 MINUTES, meaning a quick walk over the treated band was not sufficient. For pyrethroids it is much shorter, but still could be longer than the time they actually spend on the surface.

So, I think that Demand, Cy-Kick, and Cynoff WP would be perfect choices, and now I expect to hear anger from those who successfully use Suspend, which also is an excellent product but which may have a different nature. Treating insects or spiders directly with any of these insecticides will give a very different result, and now the suspended concentrates like Suspend may work more quickly, as the a.i. may be more readily available and move quickly into the insect. Wherever possible you also can evaluate the exterior of your accounts to see what physical changes can be made to discourage these invading bugs. This helps take away some of the pressure to rely totally on pesticides. If you can remove obvious pathways such as branches that forces the bugs down onto your treated perimeter. Closing any openings you can forces the wandering bugs to spend more time on your treated surfaces looking for the next entry point. Creating a cleared area around the foundation helps discourage bugs from moving across it, and removing piles of wood or debris against the foundation also keeps bugs at bay.

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