An alternative
Although the ThermaCELL Mosquito Repellent is most effective against mosquitoes, it has also been shown in field testing to be effective against black flies (Prosimulium hirtipes and Simulium venestrum), no-see-ums (Culicoides, also known as biting midges), and phlebotomine sand flies.
ThermaCell
Killing mosquitoes is an endless job with one of the zappers... if you were in an enclosed acre it would work, but killing off the local ones creates a vacuum and all the mosquitoes in the surrounding thousands of acres fill it back in shortly.
"We cover 7,500 acres along the Savannah River," he said. "Years ago, the Centers for Disease Control estimated breeding at 100 million mosquitoes per acre. Luckily they don't all breed at once."
Savannah Morning News (free subscription required)
Killing them might work if there was a widespread agreement to use a particular method, but it can't work without almost universal cooperation.... and the method chosen has to be effective.
Repelling them effectively works locally, but to eradicate them completely requires rehabilitation of breeding grounds.... and this, too, must be done in a widespread, cooperative manner if it is to succeed.