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Mud Wasps

These girls took up a warm nursery in the air inlet of a Monitor MPI boiler we installed 19 years ago. The boiler was not holding a flame and I thought this was the problem, but after removing the nests, the problem persisted and it turned out to be a bad regulator on a propane tank. I give a big thanks to my manometer.

8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hourTwo btu/ per sq ft for degree difference for a slab


  • Gordy
    Gordy Member Posts: 9,537
    Industrious creatures aren’t they?
  • Leon82
    Leon82 Member Posts: 684
    EBEBRATT-Ed Member Posts: 13,456
    We usually find them in gas regulator vent pipes when vented to the outside. Have also found infested roof top units. I confess to love watching them die when the heat is turned on the first time and they are trapped in the gas burner vent.

    We once had a job with so many bees in the rooftop units we had to cover the rtu's with a tarp and spray bee killer under the tarp.
  • flat_twin
    flat_twin Member Posts: 338
    If you have a mud dauber nest in a tight place that's hard to clean, try hydrogen peroxide. It dissolves the mud nest nicely. I collect old white gas appliances. Those wasps are notorious for building nests in the air passages of the burner manifolds.
  • Erin Holohan Haskell
    Erin Holohan Haskell Member, Moderator, Administrator Posts: 2,075
    JUGHNE Member Posts: 10,581
    Having been attacked by occasional wasps and not having any spray for them, it has worked to spray them with the blue gas leak bubbles. Even WD 40 has worked.
    Their wings get wet and they fall to the ground. You have to be a quick foot stomper to kill them as they will recover shortly and then are really angry.
  • Sal Santamaura
    Sal Santamaura Member Posts: 483
    As a wee tyke in the 1950s, visiting my aunt and uncle way out on lawn guy land, I was bitten by wasps from a not-too-visible nest in the hidden corner of a heavy wooden trellis. My uncle, a house painter, went into his shop and came out with one of the gasoline-fired torches he used to remove old paint. It made quick work of the nest's occupants.

    That approach probably wouldn't be wise near thermoplastics in a 1999 boiler. :)
    JUGHNE Member Posts: 10,581
    Hairspray and a Zippo used to work also. ;)
  • Leonard
    Leonard Member Posts: 903
    edited November 2018
    Was working on electrical box in late fall, was cold out. Saw some wasps not moving , assumed they were dead. I brushed them out. Apparently one landed on my leg. While later it "thanked" me for warming it up by stinging me. It quickly became a smear.

    Only good thing about it was wasp was so cold it couldn't squeeze very hard and didn't inject much venom.
  • ratio
    ratio Member Posts: 3,408
    My most common response is to run around screaming & waving my arms. I'm not too worried about getting shocked, not too scared of heights, but I'm afraid of getting stung. Go figure.
  • https://upload.wikimedia.org/wikipedia/commons/9/93/European_wasp_white_bg.jpg

    These Vespula wasps are the worst. They are very aggressive if you get near their nests and are the ones that go after your steak or chicken at a BBQ.

    It's hard to stay calm when they show up, but they're after your food and not you. I just wait until they land on my plate and squish them with my fork.

    They have two kinds of nests: above ground or underground. I pour a pint of kerosene down their entry hole at dusk for the underground ones. The above ground ones have to be immersed in a safe insecticide solution, like Sevin.

    In breeding months, the adults forage for food and return to the nest where they feed the young. These young wasps secrete a sweet substance to reward the adults that feed them which makes the adults eager to go get more food. However in the Fall, breeding season is over and because the adults aren't getting the reward any longer, they get irritable and this is when they will sting, unprovoked.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hourTwo btu/ per sq ft for degree difference for a slab
    EBEBRATT-Ed Member Posts: 13,456
    Stepped on a nest of yellow jackets in the ground a few years back while weed wacking. Was not fun, about 4 or 5 went up inside my pant leg.

    Lucky for me I am allergic to dust, mold, dogs, cats. trees and a few other things etc

    But not bees!
  • 1Matthias
    1Matthias Member Posts: 148
    I usually blast those with red-can brakleen. Cheaper then raid, and far more effective. It will literally knock them out of the air dead upon contact.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,599
    edited November 2018
    4 years ago we did some landscaping around our driveway. I bulldozed a hill and made a terrace with large ~2foot rocks on the drop off, the driveway being the lower part and a newly planted evergreen hedge being the upper part.

    The large rocks must have had some space behind them, right where I park my work van I noticed a few yellow jackets flying in and out around one. I waited until night and emptied an entire can of foaming Raid in/on/around the hole. Thinking that should take care of that I somewhat eagerly awaited the morning to see if the activity had stopped. Well with a few dead ones on the ground there was still flight in and out of the hole, one ever 2 seconds or so I recall.

    I did some Googling and found several posts about soap and water at the hole would mess them up, emptied about 1/2 bottle of Dawn followed by a good garden hose douse of water. Next morning no dead ones and about every 2 seconds....

    Some more Google suggested I build a trap for them. My son and I made two traps out of 2 litre soda bottles with apple juice and hotdogs as bait in one, and raw hamburger and raw chicken in the other. Several days went by and not a single one went into either trap. Some type of vermin "stole" my trap with the raw meat.....

    Now miffed, I did the unthinkable. I poured 2 gallons of gasoline all over the entry point, all around the rock and the surrounding ones as well, positive that death would come upon these little [email protected]****ds.

    Next morning, several dead ones and many swarming around and none going in or out "got em" I thought to myself as I left for the first job of the day. When I returned home, there was much activity in the air and in and out of the entry point. I exited the van through the other door... pondering how I could get rid of there things. Spray foam the entry, fly a drone near and chop em'?

    Well, now it's war time, the gasoline has killed my wife's succulents and any thought of my parking space from not smelling like petroleum.

    I did something I should not tell, something, we are not supposed to do as professionals. I brought home a recovery cylinder of R22 (this was before that went sky high) and in the evening I pushed the hose as far down the hole that it would go, connected it up the liquid valve and opened it. Fog came out of every rock either side of the hole and I smiled. I let the liquid go for about 30 seconds and removed my evidence.

    The next morning, nothing... no dead ones on the ground, no flight, no buzzing, nothing.

    Looking back, I should have used propane in liquid form, but i must admit i was not thinking clearly at that point.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • I'll pay you $1,000 for movie rights.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hourTwo btu/ per sq ft for degree difference for a slab
    Solid_Fuel_Manrick in Alaska1Matthias
  • Jackmartin
    Jackmartin Member Posts: 196
    I finally purchased a good manometer Testo 510 what a difference. Good thing mud bees do not sting, they are the first bees out in the spring here, I still do not understand how they survive 40 below. When you see mud bees on the Celia in the grass you know it really is spring. All the best and enjoy the festive season. Jack Manitoba, Canada
  • Jackmartin
    Jackmartin Member Posts: 196
    To caught wasps in a trap you have to make sure the cap is one way and IT MUST BE YELLOW. Wasps are attracted by the color yellow. We hang up 2 litre drink bottles with the yellow caps and they caught a woeful amount of wasps.
    The best bait for wasps ;the thing that is causing an epedimic in obesity, sugered Coke the little devils cannot resist it
    All the best Jack
  • nibs
    nibs Member Posts: 499
    Chain sawing 4" saplings, clearing my property, cut down a stick with a wasp nest, dropped the saw and gumbooted it out of there, just a few wasps followed me, so stopped running. Went back to look at the saw, idling on the ground, wasps attacking it with gusto. Cut a long limb with my machete and reached out to flip the shut off switch. Saw stopped running, wasps left having successfully killed the enemy saw.
  • ratio
    ratio Member Posts: 3,408
    @nibs, that's impressive!

    I was helping to move a grill this summer. I felt my fingers mash something crunchy/squishy under the side that I had picked up. When we finally set it down, I peeked underneath to see what it was. I had crushed a middling small wasp nest, there were 1-2 adults crawling on it no less. IDK why I didn't get stung, but I'm sure grateful that I didn't.

  • Jamie Hall
    Jamie Hall Member Posts: 21,117
    I had a rolled up rug on a porch once. When i went to unroll it, come to find out the little beggars had built a nest in the centre of it. They took exception to being unrolled. About six of them got me. I have a long range wasp/bee spray in a can, so that got the rest of them after I finished unrolling the rug with a long pole...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Mountain bike riding in the hills just north of us when we came upon some horses that had disturbed a yellow jacket nest. We waited about half an hour and tore down the trail as fast as we could, but the yellow jackets were waiting for a ride and climbed on my back, stinging me all the way down the mountain. I got sick and almost passed out.

    After all that, I keep bees and enjoy their company. Whenever I get frustrated with humanity, I go outside and watch the bees come and go.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hourTwo btu/ per sq ft for degree difference for a slab