Standing water is a breeding ground for mosquitoes. In arid regions, rainwater is saved for crops and gardens, but these containers can also be a haven for mosquito larvae. The basic strategies to combat them--short of emptying out the rain barrel--are: mosquito-eating fish, larvacides, and screening. The main strategy is to kill off all the larvae, and let the adults' short lifespan (a few weeks) take care of itself. Does this Spark an idea?
Instructions
1. Drop a fast-acting larvacide into the container. These are often effective for up to three weeks. (Reference 1) They are available at garden supply stores.
2. Follow up with a longer-acting larvacide for long-term control. Donut-shaped, these float on the top of the water where the larvae have to drink. With a slower release, they are often better for follow-up than immediate eradication. (Reference 1)
3. Cover the barrel with a screen. If a rain gutter is the source of water, the barrel can be fully enclosed with the downspout feeding into a hole in the barrel lid.
4. Toss mosquitofish into the barrel, if you aren't comfortable using a larvacide. They are cold-tolerant, and can live in just about any type of water, including a wide range of salinity. They eat almost any form of vegetation (Reference 1), so you may not need to give them any food beyond the mosquito larvae and any leaves that fall into the barrel.
Tags: into barrel, mosquito larvae