Eliminate mosquitoes by eliminating stagnant water

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The most effective, cheapest way to control mosquitoes is to eliminate the standing water that larvae need to develop. A dry yard doesn’t have mosquitoes. It’s really that simple. Below is a list of objects to get rid of or dump regularly. Please share with your neighbors.

1. Gutters

This is at the top of the list because almost all houses have gutters and almost all homeowners hate to clean them out. Check for blocked gutters weekly if you have a lot of trees nearby. If gutter status is hard to see, buy a drone to facilitate inspections. If you can’t afford a drone just get an extra-long, telescoping selfie stick for your smartphone.

2. Flexible downspout extenders

Flexible downspout extenders are perfect for mosquito larvae — the ridges hold water and the black absorbs heat from sunlight (thus speeding development). They are especially bad if nestled in shrubs and ground cover. Note that they hold water even if they are sloped downward. Get rid of them. All of them.

3. Tarps

If you leave a tarp in your yard, you’ve created lots of nooks in which water and debris will accumulate. I frequently see tarps covering soggy logs that owners seem to have no real intention of ever splitting into firewood. I think people view tarps as cloaks of invisibility, magically hiding loathsome to-do items from spouse.

4. Toys

Sandbox toys, sleds, wagons, and kiddie pools seem as if they were specifically designed to encourage mosquitoes. I.e., even when stored upside down they have nooks that collect enough rainwater to allow mosquito larvae to mature. Store them in the garage. If you think covering them with a tarp will work, please see #3.

5. Bird baths

Everyone should have a bird bath. But if you do, you need to either have a water bubbler/agitator (mosquitoes hate that) or you need to kill the larvae by adding granules of Bacillus thuringiensis var israelensis (abbreviated, Bti). Bti is extremely effective: you can add it a container that has thousands wriggling of larvae (see movie) and they will all be dead within hours. Just add it every two weeks and your bath will always be mosquito free. But don’t forget — make yourself a smartphone reminder or write on paper calendar.

Bird bath next to purple coneflowers

6. Trash and recycling bins

If you can’t store your trash and recycling containers under a roofed area, keep a lid on them. I found the ones below behind a local church. Tens of thousands of larvae within.

Recycling bins with stagnant water

7. Watering cans

Watering cans are rarely transparent so you can’t see the mosquito larvae inside, but they are present if you leave them around the yard when it’s been raining a lot. Store them empty, in garage.

8. Wheelbarrows

Just keep them propped up vertically so they don’t accumulate rain water. Or drill holes.

9. Rain barrels

Just put screening over the top. Or add Bti every other week. I don’t recommend adding mosquito-eating fish because they die when water level gets low (plus the fish suffer before dying).

10. Pot saucers

Pot saucers are unneeded outside so it’s easy to eliminate them. If you like them for decorative reasons you’ll need to add Bti regularly. It’s better to just get rid of them because you’ll eventually forget. You know you will.

Other places where mosquitoes larvae thrive

Other objects of concern are: pool covers, pot saucers, grill covers, plastic kid toys, tires, unattached hoses, empty glazed pots, shovels, construction materials, garbage cans, garbage can lids, containers in recycling bins, bottle caps, cemetery vases, decorative shells, empty coconuts, papaya tree stumps, downspout troughs, spigot drips, ollas, pickup truck beds, window wells, septic tanks, uncapped metal fence posts, animal tracks. Mosquitoes will also lay eggs inside in toilet bowls, animal water dishes, and French drains.

  • Recycling bin lid
  • Buckets at community garden
  • Plastic bag with stagnant water
    Garbage bags
  • Water sprinkler with stagnant water
    Upside-down sprinklers
  • Pool floats
  • Plastic mulch sheets
  • Driveway potholes
  • Fire pit with stagnant water
    Fire pits
  • Bamboo garden stakes
    Bamboo garden stakes
  • Bamboo culm stumps
  • Tree holes
  • Sump pump outflow with stagnant water
    Sump pump outflows
  • Uncovered dumpster with stagnant water
    Uncovered dumpsters
  • Uncapped, hollow traffic barriers filled with stagnant water
    Uncapped traffic barriers
  • Basketball hoop ballasts

Templates for better posters

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There’s been a frenzy of discussion on Twitter this summer about conference poster design (see #betterposter, #betterposters, #butterposter) so perhaps it’s a good time to re-share my Powerpoint templates. If you’re new to posters please see my page, “Designing conference posters” for details.

Below is a standard horizontal template. I recommend 500-800 words and 1 or 2 graphics that are understandable without you needing to explain them.

poster-template-horizontal-1-purrington

Note that there is no requirement for the text boxes to have a line around them — it’s easy to set line width to zero. And if you want to delete the background color (gray, here), you can eliminate the “rectangles within rectangles” look. Totally up to you.

If you want to include a QR code, put it at the bottom so that it doesn’t distract from your interesting graphs and illustrations. Like this:

But be cautious about including a QR code. By design it invites a viewer to fire up their camera phone, and I’d wager that most will also take a pic of your entire poster. So skip the QR code if you don’t want people to take pics of your poster. A compromise is to print business cards that have the QR code (as well as poster title, your name, your email address) and then leave them in an envelope pinned next to your poster (“please take one!”).

Here’s a template that moves the Literature cited, Acknowledgements, and Further information to the far right column … which causes the Materials & methods and Results areas to have more room. But the Conclusions box gets squished (such is geometry).

poster-template-horizontal-2-purrington

Here’s a template that might work for a humanities topic. I’ve chosen to have a question/result/conclusion flow (from left to right) inside the main arena, but you can always rearrange. There are also no rules about section names — just redo those, too.

poster-template-horizontal-3-purrington

The final template is a portrait-style one. For this orientation I think it’s critical to put the least important sections on the very bottom (that position is really hard to read without stooping).

poster-template-vertical-purrington

If you’d like to read an article about the better posters frenzy, here’s one from Inside Higher Education in which I’m quoted a few times.

Trypoxylon collinum defending nest from cuckoo wasp

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Below is a series of photographs of a cuckoo wasp (likely Caenochrysis sp.) attempting to gain entrance to a nest of Trypoxylon collinum (Crabonidae) to oviposit. Normally the cuckoo wasp will just wait until the nest is empty, but on this occasion she took more active measures. The nest is inside a section of Monarda fistulosa (wild bergamot) and is packed full of paralyzed spiders.

The first photographs shows the cuckoo wasp slowly approaching while the guarding male gnashes his mandibles and looks threatening. This goes on for several minutes. The cuckoo wasp just gets closer and closer.

Finally the cuckoo wasp is close enough that the male lunges out. It was so fast he’s just a blur. The cuckoo wasp doesn’t back up.

The male continues to parry with the cuckoo wasp, which also is equipped with formidable mandibles. At no point during this interaction do I see the cuckoo wasp back up. She’s completely calm.

Here’s where I was surprised. Out of nowhere the female Trypoxylon wasp comes back and the male immediately leaves the nest to escort her back inside the stem (as he always does). In that instant the cuckoo wasp darts inside to oviposit. I didn’t catch any of this drama but the photograph below shows the male outside the nest and the female inside (you can see her head). They must surely know there’s a parasitic wasp inside, laying eggs, right?

Now comes the part where the female disappears into the nest for a few seconds. I can hear loud buzzing. Then the female leaves and the male goes back inside. The cuckoo wasp is still inside.

The final photograph is the male glaring at me. The cuckoo was is still inside the nest because I can hear her buzzing. After about 20 minutes I can still hear her. Then it becomes quiet. The tube was walled up the following day so I’m guessing the trypoxylons entombed the cuckoo wasp. I can’t confirm this, however, because the two days later when I checked the tube it was uncapped. Perhaps the cuckoo wasp recovered from being paralyzed or damaged and chewed her way out, or maybe a bird came and pecked away the cap — there’s no way to know.

In researching this phenomenon I found one paper with good detail about how cuckoo wasps gain entry to the nest. According to Muschini and Donatti (2012), a Chrysididae will approach a nest of Trypoxylon agamemnom from the top and then attempt to slide in between the male’s antennae. I would love to see a video of that.