Question
Seemingly overnight, I have a 4-5" hole in the grass in my front yard that is the opening to a bee's nest.  Bees are very actively flying in and out of the hole throughout the day.  I noticed them while mowing when I drove my John Deere over the hole.  What is the best, safest way to get rid of them?  My wife has a severe bee/wasp allergy and we are now quite nervous.  Thanks, John

Answer
John,

This is a ground nest of a social wasp. In the US we call these wasps yellowjackets. The nests start in late spring and will continue to grow through fall when they "die" as the weather gets cold. By late summer/early fall the nests can become very large and dangerous with thousands of wasps. The same nests can be built above ground (aerial nests) and below ground. They generally have only one or two entrances.

The nests are very sensitive to sound or vibration and will swarm toward any low frequency rumble so be very careful when approaching a wasp nest with a lawn mower or brush cutter.

You can treat these nests now while they are relatively small. Use a "wasp & hornet" type aerosol insecticide. I prefer the new aerosols that are based on plant essential oils (see link below) but there are others. In the evening after sundown carefully approach the nest opening and spray about 1/2 can of insecticide into the opening then put a rock over the hole to seal it in. Be sure you have an escape route mapped out in case the wasps swarm when you start to spray (usually they don't).

Here's a link to more detailed information about wasp nest control http://www.livingwithbugs.com/yel_nest.html that may be useful.

Jack DeAngelis, PhD
Extension Entomologist (ret.)
My website about home and garden pests: http://www.livingwithbugs.com