Hi Lloyd,
You wrote:

"3. Buy a can of spray and do the job yourself.  I always give some detailed
instruction with this alternative, such as:  only spray after dark and with
a flashlight; get the spray into the hole; etc.

I am advised that since I don't have an application license it is
technically illegal for me to be doing #3.  However, my thinking is that if
we can't help out our neighbors then why are we here?"

I also get many hornet calls and also advise the citizens on their options very similar to what you do with two additions as follows:
1.  Just this year I found someone around here who collects hornets to sell for venom extraction.  They offer to remove hornet nests free for people in the area.  I have refered many people with problem hornet nests to them - nice to have someone to refer them to that will help them with the problem.
2.  If they are too far from the folks in 1 above I tell them how to use detergent solution to kill the nests if that is an option - it works well on nests in the ground but of course is not to be used on those in a building because of the fairly large volume of water required.  Usually adivse to try a bucket of detergent water to flood the nest.  A 1% - 2% solution is fatal to insects but must contact the insects to work and may have lower environmental effects that pesticides ( wasp and hornet killers are usually formulated for quick knockdown and very low toxicity to humans) or if they are reluctant to use pesticides it gives them an alternative.

FWIW

blane



******************************************
Blane White
MN Dept of Agriculture
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