flying insect

[browsetree]

I live in Indiana and have never seen this insect before.  Maybe someone on here could tell me what it is.  I saw this insect after my neighbor had her maple tree cut down due to carpenter ants.

The insect body looks somewhat like a mosquitoe in color but much larger.  The back end of in kind of curves up in a hump shape, and it has a stinger like thing coming off it's rear end that is about 3 inches long.

One of the guys cutting down the tree said he didn't know what it was but that he was told they kill maple trees.  Someone else told me that they eat mosquitoes.

Does anyone know what it is ?  Thanks

[Fern57]

Not sure what mosquito coloured would be, but was it something like this:
http://www.photon-echoes.com/images/nature/bugs!/Ichneum onoidw.JPG

This one was almost 8" long from antennae to the end of the ovipositor (the stinger like thing - is actually used to deposit eggs).