Question
I think I have a burrowing insect on my property.  I'm inquiring to find out it is an insect, and if so, what kind.  Here's the specifics:  I live in Connecticut.  At a spot where the edge of my lawn meets my sidewalk, a hole has been made into the earth.  It's about 3/4" in diameter, and it enters the ground at a diagonal angle.  The hole appeared just a few days ago (in mid-July) and adjacent to the hole was one or two cup's worth of dirt, which had been expelled from the hole.  I removed the excess dirt yesterday, and today another cup or so of dirt is outside the hole, so the hole is still being "excavated".  This is the third summer in a row that this has happened, and actually, while the last two summers only one hole was dug, this year there are three holes, in three different places along the sidewalk.  Your reply will be much appreciated!

Answer
Dave,

This sounds like a cicada killer wasp (see http://en.wikipedia.org/wiki/Eastern_cicada_killer for info). These large wasps burrow in the ground and can kick out mounds of loose soil. The wasps are not aggressive and generally pose no threat to people.


Jack DeAngelis