I have had it with bloody mosquitoes at outdoor dinner parties. To prevent the little blood suckers from ruining the your summer, drastic measures are necessary. Here are some of the most effective (or, at least, most satisfying) methods for your upcoming insect genocide.
The first method of controlling the mosquito population in your yard, the use of repellents, is the least violent -- gently persuading the marauding insects to hunt for blood elsewhere.
Spray-on repellents like Off or Aeroguard, all of which utilise the chemical DEET, are very effective -- so long as you don't minds smelling like a camp site. If you're going for a dinner party with less of a backwoods feel, try a mosquito coil instead.
Mosquito coils burn Citronella oil. This yellow liquid is derived from a species of lemongrass, is a proven insect repellent -- it's been listed by the FDA in the US as a Generally recognised as Safe biofungicide since 1948. It works because the smell of citronella masks the CO2 we exhale that mosquitoes find attractive. Mosquito coils, however, are generally not as effective as sprays and dissipate quickly if there is any amount of wind.
Over in the US, the CDC also recommends any product containing Picaridin, Oil of Lemon Eucalyptus, p-Mentane-3,8-diol (a synthetic form of Lemon Eucalyptus oil), and IR3535 (a biopesticide used in Europe for the last two decades) if you insist on going the spray route.
Another option is to install bug lights. These opaque, yellow bulbs work because humans and insects perceive different wavelengths of light -- humans see longer wavelengths from blue to red, while insects tend to see shorter the wavelengths from ultraviolet to blue. This is why bugs congregate around both conventional light sources and black lights as well. By coating a bulb in an opaque yellow finish, the light it emits is essentially invisible to insects. And if they can't see a light source, they can't swarm there. The problem of course is that everything in your yard is now tinted yellow.
If your yard is drowned in yellow light, everything reeks of Citronella, and you're still getting bit, well, you've only got one option -- all-out war. Now you just need to make sure you bring a big enough weapon.
If you prefer chemical warfare, misters are the way to go.These devices release an ultra-fine mist of insecticide that kills insects on contact (and/or a fog of repellent) over a set coverage area. Fancier models like the All Clear 4000 can cover up to 3000 square feet with effects typically lasting a few hours.
If the thought of dousing your back yard wholesale with the insect equivalent of mustard gas makes you uneasy, you'll want to take a more targeted approach -- trapping. Mosquito traps perform the opposite function as Citronella candles -- instead of masking the CO2 we breath out, traps duplicate it. These devices work either by converting propane into a stream of CO2, heat, and water vapor to attract the biting insects -- though some use chemical or visual attractants as well. Mosquitoes are lured into a trapping bag where they eventually dehydrate and die.
Traps are an effective long-term solution to controlling the local mosquito population, but they certainly aren't very satisfying -- unless you count occasionally throwing away bags of dead insects as satisfying. What you want is something that electrocutes the vicious little bastards and lets you know it's working with a with satisfying ker-ZAP. You want a bug zapper.
Bug Zappers have been around since the 1930s. They use a fluorescent light to attract insects and an electrified grid surrounding the lights to kill them. Now, while listening to mosquitoes meet their demise at 2000 volts makes for a great summer evening, zappers also attract and kill a number of beneficial insects as well.
Now that you've got them on the run, it's time to take a page out of General Sherman's playbook and start your own scorched earth policy. An operative once said, "If your quarry goes to ground, leave no ground to go to" and that's exactly what you need to do.
Mosquitoes actually begin their lives under water. Females will lay their eggs in just about an standing pool of water they can find, so that's where you strike first. Keep your rain gutters clear and your unused bird baths empty to reduce their breeding grounds. If you keep a rain barrel, install a drip oil can. These devices maintain a thin sheen across the top of the water -- drowning the larvae already in there and preventing more from being deposited.