This is an answer to Jim Croft's question on use of diatomaceous
earth/silica dusts for insect control.  I find that this is one of the
most effective of the non-toxic pest control options (i.e. non-toxic to
humans).  It is also active for a long period of time.  The only problem
you have to watch out for is its use in areas of high humidity.
Basically, this material is part of the family of clays which are
hygroscopic.  I expect though that your geographic area does not have a
problem with humidity.  However, you should be careful about placing the
dust in areas with waterpipes, sinks, toilets, kitchens (all areas where
insects do congregate), since leaks and spillage on the clay will defeat
your purpose.  I also would not use silica dust anywhere near computers
or in places where there is an unavoidable constant draught of air--you
certainly don't want airborne clay.  You might also look for diatomaceous
earth which includes natural pyrethrins (from Chrysanthemums) in the
formula--this kills the insects more rapidly than the slow dessication
effect of pure clay.  I recommend that you use diatomaceous/silica dusts
in basements (if dry), under shelves and cabinets, in wall cavities.
Hope this helps!
Prof. Linda Ellis, Director-Museum Studies Program,
San Francisco State University.
FAX: 415-338-2514
e-mail: [log in to unmask]