They are the bane of my existence in the summer. I find that tempo dust is the best at extermination but you also need your neighbors to do the same. And keep a tennis racket handy. What you outlined above is supposedly true as well.

 

…. I put down a coating of bifenthrin granules last year.

You're on the right path but …. gitchyew sum liquid (like a gallon) of bifenthrin (I.e., TalStar is sorta on sale right now: https://www.domyown.com/talstar-professional-insecticide-p-97.html ) and a 2-gal watering can (w the hole thingy spout on a long neck)

The front of the asphalt pad comprising the 200-yard firing line of the main rifle range at our home club was inundated with those suckers and the club's old guard told me, "Those things have been in the ground there since the pad was poured, nothing'll ever get rid of them." (These guys were literally raised at this club and some of them are in their 80's so, I didn't doubt the longevity of the problem).

I made 'em a bet for a pizza pie they wouldn't be there the following summer and they guffawed and took the bet.

That July I went in with about a quart of TalStar left in a gallon jug which I measured about 2oz into each 2-gal watering can and slowly and methodically "watered" (saturated) the soil. There were so many openings it made no sense for me to try and only do around each opening at a time!

The soil wasn't "hard" but, it was drier than moist; and, I WOULD HAVE GOT A LOT MORE BANG FOR MY EFFORT HAD I WAITED UNTIL JUST AFTER A RAIN (I took 2-1/gal jugs of water for making my mix innthe watering can but, there was no practical way to run a water hose to the area to pre-wet the surface and break the dry surface tension).

That was July 2020 and I collected my bacon sausage burger pepperoni ham black olive mushroom and extra cheese across pizza in September of last year, 2021. (Silly old world gentlemen: a) had not yet heard about my appetite; and b) obviously had pictured in their minds the kinda pizza they'd share with their kindergarten age great grandchildren! :lol:

Oh. Now 2 years later and still no sign o' those suckers ever coming back! :thumbup:

I was only able to do that because there:
a) were no flowers present that might attract pollinators; and,
b) was no creek or other water nearby for many, many hundreds of yards from that spot -

- if the granules you spread don't do the trick (I hate to say but, I doubt they entirely will) hopefully there isn't anything preventing you from using the soil drench method as well.

 

…. I put down a coating of bifenthrin granules last year.

You're on the right path but …. gitchyew sum liquid (like a gallon) of bifenthrin (I.e., TalStar is sorta on sale right now: https://www.domyown.com/talstar-professional-insecticide-p-97.html ) and a 2-gal watering can (w the hole thingy spout on a long neck)

The front of the asphalt pad comprising the 200-yard firing line of the main rifle range at our home club was inundated with those suckers and the club's old guard told me, "Those things have been in the ground there since the pad was poured, nothing'll ever get rid of them." (These guys were literally raised at this club and some of them are in their 80's so, I didn't doubt the longevity of the problem).

I made 'em a bet for a pizza pie they wouldn't be there the following summer and they guffawed and took the bet.

That July I went in with about a quart of TalStar left in a gallon jug which I measured about 2oz into each 2-gal watering can and slowly and methodically "watered" (saturated) the soil. There were so many openings it made no sense for me to try and only do around each opening at a time!

The soil wasn't "hard" but, it was drier than moist; and, I WOULD HAVE GOT A LOT MORE BANG FOR MY EFFORT HAD I WAITED UNTIL JUST AFTER A RAIN (I took 2-1/gal jugs of water for making my mix innthe watering can but, there was no practical way to run a water hose to the area to pre-wet the surface and break the dry surface tension).

That was July 2020 and I collected my bacon sausage burger pepperoni ham black olive mushroom and extra cheese across pizza in September of last year, 2021. (Silly old world gentlemen: a) had not yet heard about my appetite; and b) obviously had pictured in their minds the kinda pizza they'd share with their kindergarten age great grandchildren! :lol:

Oh. Now 2 years later and still no sign o' those suckers ever coming back! :thumbup:

I was only able to do that because there:
a) were no flowers present that might attract pollinators; and,
b) was no creek or other water nearby for many, many hundreds of yards from that spot -

- if the granules you spread don't do the trick (I hate to say but, I doubt they entirely will) hopefully there isn't anything preventing you from using the soil drench method as well.

I am going to give this a try.

The strip along our curb and the lawn edge along the sidewalk got blasted last year with these. I found delta dust in the holes eventually took care of them and I had hoped I would avoid the swarm this summer. I also overseeded and really tried to thicken the lawn along the sidewalk and curb strip. Grass came in pretty nice in those areas this spring. I figured I was good.

LOL. nope. Didn't work. I have swarms of these things in the same spot again. Buzzing around constantly. Now only a couple of burrows have been dug so maybe the thicker lawn is helping prevent the lawn damage I had last year but I am looking for a way to get these things to just disappear and be gone forever. Our kids don't really want to play in the front yard and people just avoid walking past our house (maybe not a bad thing, hahahaha).

I wonder if treating with this will act as a deterent going forward.

 

I am going to give this a try.

The strip along our curb and the lawn edge along the sidewalk got blasted last year with these. I found delta dust in the holes eventually took care of them and I had hoped I would avoid the swarm this summer. I also overseeded and really tried to thicken the lawn along the sidewalk and curb strip. Grass came in pretty nice in those areas this spring. I figured I was good.

LOL. nope. Didn't work. I have swarms of these things in the same spot again. Buzzing around constantly. Now only a couple of burrows have been dug so maybe the thicker lawn is helping prevent the lawn damage I had last year but I am looking for a way to get these things to just disappear and be gone forever. Our kids don't really want to play in the front yard and people just avoid walking past our house (maybe not a bad thing, hahahaha).

I wonder if treating with this will act as a deterent going forward.

How is it going this summer?