Tricky wasp nest

Old 09-03-22, 03:08 PM
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Tricky wasp nest

There's a wasp nest somewhere inside this crawlspace vent. I tried spraying wasp killer but it's useless because the nest may not be in direct line of sight from outside this vent. What would be a better solution? I don't want to go inside the crawlspace to confront them

One thing I'm worry is if I accidentally stir up the wasp nest, how far would they go to search for and attack a person if I immediately run inside the house? Would they attack a neighbor?

Right now I have 3 potential methods:
(1) home made bug zapper
(2) shop vac with soapy water inside the tank. Wasps sucked into the vac would drown.
(3) wasp trap bought from hardware store

What's the best one to try?

wasps flying in and out thru this vent
The photo doesn't show many wasps because it's a shoot and run photo
Old 09-03-22, 06:08 PM
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This is probably a case where $200 to get an exterminator out is worth it. You could try using a powdered insecticide like Delta Dust, which is applied with a bulb duster. But if the nest is out of reach of a spray, it's likely out of reach of the dust and if you can't get insecticide into/onto the nest you won't solve the problem. It's possible you can get to the nest by pulling out the vent screen, but that's not something you want to do without protective gear.

How aggressive they are depends on exactly what type of wasp they are.
Old 09-03-22, 07:07 PM
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Short of going in or hiring an exterminator, my old man hooked up a shop vac to a hole where he knew wasps were getting behind siding. Would have to run it for a helluva long time but it did work.
Old 09-04-22, 05:48 AM
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Without being able to see the nest, the size/quantity, etc. I don't know how to formulate a plan or strategy.
I've never known of a bug zapper to be used as control for a nest/hive. Are you going to put it in the crawl space?
I wonder if that would even be safe. I've no experience with that eqpt. I thought bug zappers were for night time flying insects anyway.
Shop vac will work if you have direct access to the nest and attack it aggressively. If they had a single entry/exit point, the sprays would work so I doubt that shop vac, unless from inside the crawl space, will work.
Wasp traps-If they work to any extent, they will just take some of the foragers.

I'd dress up in coveralls, cover head/face to an extent and employ a serious spot light and enter the crawl space slightly and hope to see the nest from a distance. Floor joists may prohibit direct visual sighting though.

Any insecticide, be it aero, water based, dusts, will kill the nest when you treat it directly. Sometimes direct treatment is easy, other times it isn't. Someone has to go and find the nest for successful treatment. Scattershot treatment from the screen may eventually work, may not.

Are you finding dead wasps at all? As a side note, winter will solve this problem if you can safely wait. Honeybees are the only bee/wasp/etc that over winter. Do not cover the crawl space as that will hinder their exit/enter and could move them into the living areas of the house. Keep us posted.

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