Mr. Dewey wrote:  "...leaf wasps had invaded the main chest..."
That doesn't take long to happen and can be quite dangerous.

My team of employees and I went for a two weeks summer vacations break
in 1992. The week before we partially installed the two main windchests
in an organ I had under construction in a church nearby.

At our return wasps had invaded one of the windchests grooves since
the long primary block wasn't installed on its front, leaving the
grooves accessible.  But, we were not aware of that fact.  Let's say
that when my employees started to move around and walk on the windchest
it infuriated the wasps that went out stinging all of us a few times.
One of my workers was allergic and needed the use of his EpiPen.  It's
good that he knew about his allergy and carried the needed emergency
medication or we would have had a casualty.

All five of us ended up at the local hospital ER.  The next day we
hired a team of exterminators to take care of the nasties and we asked
the church council for the installation of proper screens at each
windows.  That church was built in 1958 and had many large windows on
the long sides of the building on which a lower pane could be opened for
ventilation, but none had been equipped with screens before our mishaps
with the wasps.

Four years ago the screens needed some repairs.  They got removed but
never came back.  Since then, each time I go for a tuning job I find
muted reed pipes in the 16' Pedal Trumpet caused by insects that fell
from the large stained glass window over the organ.  Few of them wasps
again... That window over the organ doesn't have an opening for the
bugs to get out of the church and it is facing south.  As I explained
before, the insects follow sunlight and end up in the pipes below the
window.

Once I also found a black widow spider in a crate of organ pipes coming
from Florida.  It's good we were in winter and the crate spent a night
in my car on a sub-zero weather.  When I opened the box the spider was
moving but very slowly.  I recognised the species by the violin shaped
red mark on it and told my men not to play with it and kill it right
away.  Each of the pipes and the wood board making the crate have been
inspected in case another unwanted immigrant would be hiding in that
shipment but none was found.

Gilles Chouinard, organbuilder
Laval, Quebec, Canada