Currently viewing the category: "Horntails, Wood Wasps and Sawflies"
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Subject: Any ideas what this is?
Location: Buffalo, NY
August 17, 2014 9:10 pm
Does anyone have a clue what this flying bug is? Not sure if it came from the pine logs I was cutting but it also appears to have a stinger
Signature: Nick

Black and Red Horntail

Black and Red Horntail

Dear Nick,
Though we have no shortage of other Horntails on our site, including the Pigeon Horntail, this is the first example we are posting of a Black and Red Horntail,
Urocerus cressoni.  Horntails are Wood Wasps and the larvae bore in wood of dead and dying trees.  According to BugGuide:  “hosts include Fir, Spruce, and Pine (Abies, Picea, Pinus).”  

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Subject: Curious Large
Location: Hastings, MI
August 17, 2014 9:51 am
Hi,
My mom and I found this bug on a dead tree stump where there are a ton of Stump Stabbers around. The next day I found it dead on another area of the stump. I didn’t think it was a wasp since it does not have the separated thorax. It is a bit scary since it was so big, but I’m just wondering what it is since my 13 year old daughter has more curiosity than what is good for her.
Signature: Nervous Mom

PIgeon Horntail

PIgeon Horntail

Hi Nervous Mom,
You have no need to fear this Pigeon Horntail, because even though it is a Wood Wasp, they do not sting.  The female uses her ovipositor to deposit eggs beneath the surface of dead and dying trees and the larvae are wood borers.  Interestingly, the presence of Stump Stabbers makes perfect sense as the larvae of Stump Stabbers parasitize the larvae of Pigeon Horntails.  This particular female did not mature properly as her wings appear to have atrophied.

Thanks Daniel,
That is so incredibly interesting.  We see the Stump Stabber’s all the time but have never seen the Pigeon Horntail there.  We are around this stump all the time (it is huge) since my herb garden surrounds a small portion of it.  Now we don’t have to be afraid.
Thanks again,
Jenn

What's That Bug? does not endorse extermination

Subject: Caterpillars on a red-twig dogwood
Location: Chester County, PA
August 12, 2014 10:17 am
While working with a client in their garden yesterday, I noted these caterpillars on a Cornus sericea (red twig dogwood) shrub. I have not seen these before, and would like to know what they are. Fortunately, the clients were just as curious, and willing to “live and let live”, especially as there was very little foliage damage. This is in southeastern Pennsylvania, photo taken August 11, 2014.
Thank you!
Signature: The Gardening Coach

Dogwood Sawflies

Dogwood Sawflies

Dear Gardening Coach,
Though they are easily mistaken for caterpillars, these are actually the larvae of Dogwood Sawflies,
Macremphytus tarsatus, and they are members of the order Hymenoptera that includes wasps, bees and ants.  According to BugGuide:  ” Young larvae are covered with a powdery white waxy coating. Mature larvae are yellow beneath with black spots or cross-stripes above.”

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Subject: Big wasp like bug visits picnic
Location: Powell river, bc
August 8, 2014 5:21 pm
We were having a picnic at the Saltery Bay picnic/beach and this rather large bug decided to join us
August 6, around 5:30 pm
Powell river regional district, bc not far from the Saltery bay ferry terminal
Signature: Noni

Wood Wasp:  Urocerus albicornis

Wood Wasp: Urocerus albicornis

Hi Noni,
This is
Urocerus albicornis, a species of Horntail or Wood Wasp without a common name.  According to BugGuide, it is found in  “forested regions from southern boreal Canada south to NC-MP-NM-CA” and “hosts include fir, larch, spruce, pine, Douglas-fir, hemlock, and western red cedar.”  According to all the information we have read, they are harmless and do not sting humans, including this family information on BugGuide:  “Horntails do not sting: what looks like a sting is the ovipositor the female uses to lay eggs in wood.”  With that stated, we need to divulge that we just posted this very credible report that a man in England was “stung” by a European relative of your Wood Wasp.  That unverified report seems to be an anomaly.

Thank you for your reply.. She visited a bit and then with gentle nudge flew off on her way, much to the happiness of the other occupant of the picnic blanket.. Such a beautiful big bug!!!
;) noni StReMmInG

What's That Bug? does not endorse extermination

Subject: Is this a wood wasp?
Location: North Yorkshire England
August 6, 2014 2:25 pm
Hi I was at work today putting up a fence when I felt a pain in my leg. I looked and was not sure what it was I knocked it away and in doing so unfortunately killed the insect. It had however stung me and it is incredibly painful even now 10 hours later. I am from the north east of England and have never seen such a creature please help me identify it!
Signature: James Rowe

Great Wood Wasp

Great Wood Wasp

Dear James,
This is indeed a Great Wood Wasp, and we are quite surprised to learn of your experience.  According to UK Safari:  “The female (above) has a long pointed tube at the back of her body, and this is often mistaken for a stinging organ. In fact it’s an ovipositor, which she uses to lay her eggs in the trunks of coniferous trees. Despite their appearance, these insects are quite harmless.”  Knowing that and also knowing that the female lays her eggs beneath the surface of the bark of a tree, we believe it is entirely possible that this Great Wood Wasp mistook your leg for a conifer, and tried to lay eggs.  Do you use pine scented soap?  We do not believe she was trying to sting you.  It is also possible that she used her powerful mandibles to nibble at your leg.

Dear Daniel,
Thank you for your speedy and informative response. This is indeed very likely as I was at the time building a fence using pine timber and it is very possible that the timber would have come into contact with my leg. There is in all 5 “sting” marks on my leg so it is possible that she has had a nibble. It is rather swollen and painful. What could this be? It does feel like a general bee/wasp sting. Could she have laid her eggs?
Many Thanks,
James Rowe

Hi again James,
This is quite perplexing and contrary to all we have read, so we are tagging this posting as a mystery.  We suppose if you were jabbed with her ovipositor accidentally, it is also possible that she deposited eggs.  Unless you have a wooden leg, you shouldn’t have much to worry about, however, as we are not medical doctors, should any irritation persist, you might want to seek medical attention.

Eric Eaton Concurs
Daniel:
I would concur with your assessment, except I doubt she would have laid eggs.  After five attempts she may have concluded “this is not a tree.”  In any event, I agree he should seek medical attention if symptoms persist or get worse.
Eric

What's That Bug? does not endorse extermination

Subject: please help me identify this bug.
Location: south australia
August 6, 2014 12:08 am
Hey. I was walking home with my friend today and we walked pasted a shrub or a ungrow tree and there was this black bug on it with white spikes. I’m not sure exactly whether it was a spider or an insect but when I wobbled the branch it kind of moved like an octopus. It almost the end of winter and temperature was about 17-20 degrees celsius if the climate helps. The picture I am showing might not be completely clear or from the best angle so I apologise. Hopefully you can identify this bug. Cheers.
Signature: molly

Steel Blue Sawfly Larvae

Steel Blue Sawfly Larvae

Dear Molly,
When taking images of bugs, it is best to focus on the subject and not the background.  You mistook this aggregation of larvae for a single creature, when it is actually a grouping.  We could tell the branch was some type of Eucalyptus, so we searched for both caterpillars and sawflies that feed on Eucalyptus, and we quickly located an image of Steel Blue Sawflies on the Australian Native Plants Society site, but sadly, only a common name was provided.  The site states:  “Another chewing pest that can appear in large numbers are steel-blue sawfly larvae. They do most of the damage to a tree’s foliage during the night and in daylight hours they gather into groups around small branches. If they are accessible at these times they can be removed by cutting off the branches where they cluster together.”
  Armed with that common name, we next located an image on the Australian Museum site where we learned a genus name Perga and the information that “The Steel-blue Sawfly can sometimes cause extensive damage to trees.”  Our third stop was the Museum Victoria site where the Steel Blue Sawfly was Bug of the Month in July 2012.  There we reinforced the common name Spitfire for a Sawfly Larva and we got the species name Perga dorsalis.

What's That Bug? does not endorse extermination