Cicadas and Cicada Killers - Ask Extension
For the past several years the ground in my back yard has had small holes--smaller than a dime in several areas. This year those holes are more numero...
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Cicadas and Cicada Killers #879472
Asked July 30, 2024, 5:57 PM EDT
For the past several years the ground in my back yard has had small holes--smaller than a dime in several areas. This year those holes are more numerous than ever. I've also discovered MANY outer empty shells of what I believe are cicadas. My garden helper was going to put down mulch today, but decided that I better find out what was coming out of those holes before she continued. She saw some pretty angry black wasp like creatures swarming around the holes when she began to cover them with the mulch. She identified them as cicada killers and identical to the ones that had been lured into my wasp trap. So--do I have an infestation of cicadas and cicada killers? What do I do? Let nature take its course? Can I eliminate the cicada killers somehow? I think there are tunnels all over my backyard. Do I forget about putting down the mulch? Yikes! Help!
Jackson County Oregon
Expert Response
Hi Maureen,
The exoskeleton in the photo labeled "cicada shell" is the cast skin of a cicada left as it molted to become an adult.
The holes you are seeing in your backyard may or may not be from cicada killer wasps (Sphecius spp.). These are examples of the two cicada killer wasp species we have in Oregon...
https://bugguide.net/node/view/1701862
https://bugguide.net/node/view/540438
Did you or your gardener see any wasps that looked like these. If not, something else is probably making those holes.
The wasps in your wasp trap are yellowjackets and yellowjackets in the genus Vespula are ground-nesters, so maybe that is what is coming out of the holes in your yard. I think the species in your trap may be Vespula acadica, but it is a little hard to see the ID characteristics well in your photo. Here is an example of a V. acadica specimen for comparison...
https://bugguide.net/node/view/1113506
Yellowjackets are pretty fierce and are much more likely to sting than other wasps or bees. If you do determine that they are the insects emerging from the holes in your yard, you might want to take steps to lower the numbers of these wasps or to eliminate the nests.
The traps like the one you have do a pretty good job in catching yellowjackets and can be used to reduce their numbers. Ground-nesting yellowjacket nests can be tricky to kill since the soil protects the nest. If you decide you want to eliminate the nests, it would probably be best to consult a local, reputable pest control company.
Best wishes!
The exoskeleton in the photo labeled "cicada shell" is the cast skin of a cicada left as it molted to become an adult.
The holes you are seeing in your backyard may or may not be from cicada killer wasps (Sphecius spp.). These are examples of the two cicada killer wasp species we have in Oregon...
https://bugguide.net/node/view/1701862
https://bugguide.net/node/view/540438
Did you or your gardener see any wasps that looked like these. If not, something else is probably making those holes.
The wasps in your wasp trap are yellowjackets and yellowjackets in the genus Vespula are ground-nesters, so maybe that is what is coming out of the holes in your yard. I think the species in your trap may be Vespula acadica, but it is a little hard to see the ID characteristics well in your photo. Here is an example of a V. acadica specimen for comparison...
https://bugguide.net/node/view/1113506
Yellowjackets are pretty fierce and are much more likely to sting than other wasps or bees. If you do determine that they are the insects emerging from the holes in your yard, you might want to take steps to lower the numbers of these wasps or to eliminate the nests.
The traps like the one you have do a pretty good job in catching yellowjackets and can be used to reduce their numbers. Ground-nesting yellowjacket nests can be tricky to kill since the soil protects the nest. If you decide you want to eliminate the nests, it would probably be best to consult a local, reputable pest control company.
Best wishes!
