From: The Real Bev 
Newsgroups: misc.rural alt.home.repair misc.consumers.house misc.consumers.frugal-living
Subject: Re: beneficial insects?
Date: Wed, 14 Jul 2004 14:42:14 -0700

Bill Seurer wrote:
> 
> Fred Walter wrote:
> 
> > What beneficial insects do they kill (and how are they beneficial)?
> 
> "All studies of household units in domestic situations have shown that
> zappers kill everything but the occasional mosquito. The University of
> Delaware conducted the best known study where only 31 out of 13,789
> insects trapped (0.22%) were mosquitoes or biting gnats.
> 
> The majority was harmless insects, or beneficial insects such as
> parasitic wasps that help keep other pests at bay. The authors (Timothy
> Frick and Douglas Tallamy) calculated that the four million bug zappers
> that might be bought over the last four years in the USA would destroy
> 71 billion nontarget insects."

The only one I've ever seen in operation (50 years ago) was an
electrified grate placed over a box of horse manure -- readily available
bait, since it was at a stable.  Every 10 seconds or so a giant fly
would get zapped with a pleasant flash of light and a hearty BZZZZZZT. 
Good enough.

-- 
Cheers,
Bev
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The Marketing Professional's Motto:  "We don't screw the customers.  All
we're doing is holding them down while the salespeople screw them."
                                                          -- Scott Adams