Medhat wrote:

>This product (Gaucho) has been approved in Canada this year. It will  be
>used for the first time on Canola this year, 2000.

It is my understanding that the pesticide "Admire" is also imidacloprid.
This has been used on potatoes in Prince Edward Island (Canada) for three or
four years now.  But bees do not visit potato flowers, and they do visit
canola and sunflowers.  Here in PEI our beekeeping association has asked
members to be on the lookout for kills resulting from bees drinking
contaminated water in the drills.  So far no one has reported anything.

The following is quoted from an exchange on the bombus-l in 1996:

From: [log in to unmask] (Whitney S. Cranshaw)
Date: Thu, 19 Dec 1996 06:16:19 -0700

In response to:
  >
  > We have made observations on the reaction of the bumblebees and also
  > checked concentrations of the substance in different parts of the
  > plants.  We found that for several weeks after application of
  > imidacloprid, significant levels found in the plants.  Moreover,
  > concentrations in the flowers were tenfold higher that in other
  > parts of the plant.
  >
Fascinating.  This is absolutely a first, where an insecticide is
concentrated in flowers.  With other insecticides, the fruit and flower
are a major barrier to insecticide translocation.
  >
  > The most significant reaction of the bees was to avoid the flower.
  > We could observe workers attempts to visit flowers, but when coming
  > into close range (1-3 cm. from the flower) they stopped and taken
  > aback.  This response lasted for 2-6 (six) weeks after usage of the
  > imidacloprid.
  >
Again, such a response to an insecticide, i.e., a long distance
repellency (1-3 cm) is absolutely unique.  Although some insecticides
(e.g., pyrethroids) are known repellents on contact, imidacloprid has
never been demonstrated to be repellent - much less show repellency
beyond the surface.

end of quote

The observer was a company that raises bumblebees in Israel and uses them
for pollinating tomatoes (which are sprayed with Imidacloprid).

I might add that I have made the observation on three separate occassions
that bees that are put in blueberry fields that have been sprayed with the
new formulation of carbaryl (Sevin XT? or some such thing; supposed to be
harder to get carried back to the hives in pollen) will NOT work those
fields, and the effect (residual smell?) lasts for at least a week.  I don't
blame them at all, but it is hard on their pollinating ability reputation as
the pesticide company and government agriculture extension people seem to
deny to the growers that the pesticide has this effect.  It is very
frustrating to me, because it is not a difficult scientific observation:
Next to no bees were in sprayed areas;  there was normal foraging outside
those areas in same crop.  Once I put down square metre frames and counted
them;  there were about five times the bees in the unsprayed crop.

Stan