There's been a lot of buzz lately about monthly mosquito treatments. We've been asked many times if we offer this service, if we think it's a good idea, and if we think it works. The short answer is no, we do not offer a monthly mosquito service. Of course, the long answer will surely follow.
In our industry, we are heavily regulated, and rightfully so. The chemicals we apply have been heavily tested to ensure human and environmental safety, so we can only use what is registered for that particular pest. Makes our job pretty simple, as far as decisions go. For mosquitoes there are really only a few chemical options (read about our chemical free option here).
One option that most people have heard about is a garlic spray. Chemical free is always appealing, but all you have to do is google 'garlic mosquito spray' to find huge variance in reviews from people who have used it. Everyone agrees that it stinks but there is controversy about whether or not it works and whether or not it is safe for pets. We have limited experience with garlic spray, but it wasn't good. We will always suggest the eco-friendly option...if it works. We won't use or recommend something that doesn't work (in our experience) just because it's environmentally friendly. 2019 edit: there is a re-formulated product we have heard great things about but have not tried it for ourselves.
In contrast, we won't suggest something unnecissarily dangerous, such as a fogger that utilizes a chemical called propoxur. Propoxur is categorized as a non-systemic carbamate, which is fancy talk for really dangerous. It doesn't need to be ingested to affect humans, pets or non-target insects, simple atmospheric exposure can result in adverse health effects. Health Canada has actually decided to phase out the use of propoxur for mosquitoes and biting flies because of the dangers associated with its use. Google 'Health Canada propoxur' to read for yourself if you're interested in further information on this topic. It is simply one of those chemicals that we refuse to use because it isn't necessary or merited.
Another chemical, permethrin, is much less toxic and absolutely works to exterminate mosquitoes, though it is short lived. It is the product that we use for our services to control mosquitoes for events like weddings or other outdoor gatherings, which we advise will offer control for about 24-48 hours. We are extremely careful about where this product is applied to adhere to aquatic buffer zones and our responsibility to environmental protection. So if the scientific articles behind this product state that it is effective for a short period of time, and our experience shows us that it is indeed effective for that short period of time, we won't tell you that it will last a month. The science simply isn't there to back up that claim.
What science does tell us about mosquitoes and insects in general, is that they are quick to build up resistance to pesticides if the pesticides are not properly used. If an insect, such as a mosquito, is exposed to a pesticide but is not killed by it, the population slowly builds resistance. This resistance is essentially an evolutionary trait to resist the effect that the pesticide is designed to have. Human evolution is slow because we have a long time between generations (20-ish years), and it takes multiple generations for traits to develop consistently. Mosquitoes have many generations in one year so these traits are developed and passed along quickly. Since we really only have one chemical option for mosquitoes in Ontario, it is important to use that option responsibly to avoid resistance buildup, because this would essentially render the option useless. It will no longer affect mosquitoes and we will have no chemical option for control. This would have devastating effects if something like malaria or zika made its way here. We are of the belief that we should use pesticides sparingly and properly, to ensure we can protect ourselves for special occasions and well into the future. If mosquitoes are a problem for your property there are Integrated Pest Management options that we love to discuss. We can implement control measures for you or advise DIY solutions custom for your property to help you enjoy those sweet summer months.