What's That Bug? does not endorse extermination

Would you please help me out and let me know what insect this is. I have attached several photos. The photos were taken of one that was approximately the size of a silverdollar not including the tail which appeared to be about 5 inches long. There are many others in all sizes. I am concerned that these will bite or sting.
Thank you for your time.
Heather Hamilton

Hi Heather,
Wow, great photos of a female Megarhyssa species laying eggs. This is one of the Giant Ichneumons. The female uses that long ovipositor to deposit eggs deep inside wood that is being parasitized by boring grubs. We got another photo from Jared in Columbus Ohio two days ago and while we were in Youngstown Ohio this week, we saw one flying aroung the dead wood of Mom’s dogwood tree. They will not sting.

Ed. Note: (09/17/2005) We now believe this to be Megarhyssa macrurus which can be located on this site.

Update:  April 8, 2014
We are frequently asked if Giant Ichneumons can sting, and we always reply that they cannot.  We just found a fascinating article.  According to Icheumon Wasps by Lloyd Eighme on Skagit.wsu:  “It might frighten you, but if you could watch it long enough you would be amazed at what it does. It lands on the bark of a tree and crawls up and down, tapping with its long antennae, obviously searching for something. Eventually it finds the spot it is looking for and begins to drill into the bark with its long needle-like ovipositor. It has detected the larva of a horntail wasp chewing its tunnel in the wood an inch or more below the surface of the bark. The ovipositor is made up of three stiff threads, hardened by minerals, that fit together with a groove in the center. Vibrating those sharppointed threads forces them into the bark and sapwood of the tree to contact the horntail grub in its tunnel. An egg is forced down the ovipositor to parasitize the grub. If the ichneumon parasite larva killed its host, they would both die, trapped in the solid wood which the parasite is unable to chew. It only feeds on the nonvital organs like the fat body until its host has nearly completed its life cycle and has chewed its way out near the surface of the bark. Then it kills and consumes its host grub and completes its own life cycle to emerge as another giant ichneumon wasp in the genus Megarhyssa (mega=large; rhyssa=tail) to start over again. You can see both Megarhyssa and its horntail wasp host in the MG collection.
People often ask if the ichneumon wasps will sting them with their needle-like ovipositors. The wasps are interested only in laying eggs in caterpillars or other insects, but if you handle a live one it may try to sting you in self-defense. Small ones could not likely penetrate your skin, but larger ones might be able to

What's That Bug? does not endorse extermination

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