Spring is officially here so I’ve deployed my collection of mosquito traps (photographs below). In case you haven’t seen them before, each is filled with water and decomposing plant matter (hay and compressed rabbit food), then equipped with special lids (and sticky cards) that prevent females from escaping once they get inside. In addition, eggs that the female might lay are also prevented from developing. All of this happens passively, 24/7, all summer long, without the use of chemicals. I have two from BioCare (~$30 from Gardeners Supply), two from Biogents (~$24 from BioQuip), and one that I made last year (~ $5 in supplies).
Every homeowner should have them. Coupled with other preventative measures (eliminating stagnant water, reducing excess vegetation, etc.), you can knock back mosquito levels and enjoy your yard again. Five units is probably sufficient for an average yard but I plan on making a few more this summer just to make sure.
Ideally, everyone on your block should have them, too, so if you are planning on ordering some you should first send a note to all your neighbors to see whether you can make a bulk order. E.g., if you order a lot of Biogents you can shave a few dollars off of each unit. Buying a bunch might seem like a lot of money but compare it to the cost (~$700) of having a company like Mosquito Squad spray your yard with pyrethroids every several weeks (every year). Using these passive traps also saves all the pollinators that are killed by those pesticides.
Just a pic of the latest mason bee hotel I made, this one for my sister. It’s heavy, but designed to slide into a medium USPS flat rate box. Sides are cedar, top is exterior-grade plywood sprayed with a preservative. Blocks are made from old dimensional lumber (circa 1906), with 5/16″ holes that are 6″ deep. Block unit is removable so that pupae can be protected from parasites, birds, and weather once all the holes are sealed. Next spring, new blocks will be popped in while the current blocks are set outside (inside a box that has a small escape hole) to release their occupants.
For details and links on building mason bee houses, please see my earlier post. If you already have one and own a nice camera, please post photographs of residents on iNaturalist, then add to my Bee and Wasp Hotels project. There are multiple species of mason bees, plus you’ll get leafcutter bees, and nest-provisioning wasps. All of these residents will, of course, attract parasites such as cuckoo wasps.