Please becareful it can be dangerous---I have found nothing that will knock wasp down like a shot of gas (good old gasoline). Put some in a squirt bottle and spray it on them--it will knock them down.  Like I said it can be dangerous as well as smelly and messy but it will kill'em. Don't waste your time with hornet spray or wasp spray, the ones I have used they just seem to fly right through it and keep on going. They may eventually die, I dont know but the gas will take them down right now.  Good luck---if asked I will disavow ever having told you this.  
 
flyone

We had lots of wasps and mud daubers in Florida, and Home Depot sold a professional level spray that was almost instantaneous.

Mike

Thank you for the info. No Hornets and Wasps today - just high winds and rain.

we just set out a couple hornet traps and that seems to do it in a few days. They are available almost everywhere anything is sold. keep the bait kinda fresh for best results

I have used "Raid Wasp and Hornet Spray" for years. It knocks them  right out of the air, and they will not return to the sprayed area.  You should be able to find it almost anywhere.

Hi Jim and Linda, Thanks for the info. Will give it a try.

I've always loved the Bioganic product line. Made with plant oils it's eco-friendly and smells GREAT. I went to their website, bioganic.com, and see they have changed the name to EcoSMART and are selling through Wal-Mart. The wasp/hornet killer is one of my favorites because it works great and the smell is divine....MUCH better than other brands....and it's safe around kids & pets.

Froggi Donna, I check i t out also. Thank You!