Diatomaceous earth for fleas

Old 09-20-22, 08:24 PM
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Diatomaceous earth for fleas

So fleas have been terrible this year, both our dog and cat keep getting them despite repeated treatments. Earlier this year we decided to make our cat an outside only cat (she kept urinating everywhere), but apparently not before she got fleas in the basement.

Anyway, the dog doesn't go in the basement at all and we keep it shut all day every day, but there are fleas everywhere in the basement. If you go down the steps you immediately have fleas jumping all over your feet.

My MIL swears by diatomaceous earth for fleas, I put it down the steps and all over the carpeted area at the bottom of the steps and it has been there for a few days at this point but it doesn't seem like it is doing much, as there are still fleas jumping on your feet from the areas where it is.

Does this stuff take a longer time to work or what? I have some dry foggers that I am going to use when I get a chance to get the house empty for awhile, but I was really hoping that diatomaceous earth was going to work. I know I read it only works on adult fleas so is that why it doesn't seem to be making much of a difference yet?
Old 09-21-22, 05:48 AM
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First, you have to understand that controlling fleas is a marathon. You rarely can do just one quick thing and kill them all. They hatch from eggs at varying time depending on conditions and activity and you can't kill eggs so you can only attack the ones that have already hatched. So, you may have killed some fleas already but more continue to hatch. I prefer to use an insecticide and insect growth inhibitor over DE but it's still a process that can take time.

I would vacuum every inch of your floors every couple days. Then reapply DE afterwards. The movement of vacuuming will stimulate eggs to hatch. Then the DE dries them out and cuts them up, eventually killing them. Then repeat, and repeat... It is important to keep this process up until they are all dead. If you stop half way they can reproduce and re-infest the house.
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Old 09-21-22, 06:05 AM
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In my career in pest control, I've never used or known of any pro to use diatomaceous earth (DE) for fleas or any pest for that matter. If it worked, we'd use it. I suspect other treatments were also used in your mother in laws house and that is what solved the problem. DE would have value if it was applied into void spaces for roaches in walls where it would "toxify" that particular space, but as a broadcast treatment, no. Does the label allow for a general broadcast treatment like that?

What were the pets treated with? There are various pet flea meds that work well. Expensive, but they work.

The problem with fleas in vacant spaces is that the pupal cases (egg, larva, pupa, adult) will not hatch until a host comes by. They can lay dormant for up to 9 months until a host comes by. When the hosts enters, that's when the overwhelming flea hatch occurs. The adults weren't lying in wait, the pupal cases were. They literally spring out of their pupal cases as they need to feed quickly. No insecticide will penetrate the cases. When I treated vacant properties, and your basement is vacant as far as the fleas are concerned as no one goes down there, I required that the customer/real estate pro gave me access so I could walk through every couple days after treatment so I could stir up the pupal cases/adults. It would be ideal if a properly treated pet would walk through daily as the animal itself could stir up the adults on a gradual basis as opposed to an adult once in a while.

At this point, a very thorough vacuuming is necessary. Not just exposed floors, but under furniture, cushions, open sleeper couches, closet floors, under beds, focus heavily on underneath things. Pet hair, dried blood from adult flea fecal material, and dander are ideal food and harborage for the larva.

Since the basement is so bad, it's almost prohibitive to work down there so I'd consider walking through with a flea aerosol made for spraying downward rather than the total release foggers, If you've already got the foggers, than use them as the first treatment. First, long pants tucked into socks and remove cushions,overturn furniture, clean out closet floors, sump pump lids that may have pet hair, lift area rugs, etc. After preparing the basement, start in the farthest room and work your way out as you spray. I would certainly spray my shoes, pant legs.
Later that day, or the next day, I'd vacuum very thoroughly.

Make sure that all flea sprays/aeros that you use are designed for fleas and have a growth regulator in them.

Precor, Ultracide, and Alpine, among others, make flea aerosols that can be used upsidedown like a sprayer rather than a total release fogger. You want to direct the spray to the intended area. Don't buy or use any dust product for fleas, unless it was to a confined space such as a crawl space. Even then it will take eqpt beyond most diy'ers to make an even application, and deep enough into crawl.


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