>>What about the stress from being moved?  Does the defensive behavior in these hives persist or does it go away after a while?

The move is relatively short (<1 hr) and we don't bang the boxes.  I'd think any stress and memory of move should dissipate within a week.  The extra defensive behavior lasts into the following April.. 

>>I think that if it were simply a matter of pesticides there would be other problems besides just being ornery.

Some colonies come through the winter with smaller clusters and have 1-2 frames of brood at this time.  They do build up fast and I equalize by transposing strong and weak colonies.  They all get pretty much ready for the start of the nectar flow (the queens seem unaffected).

>>Have you considered getting the pollen and maybe the honey 
tested, perhaps even before during and after the goldenrod flow?  Where are these bees getting their water?

We put out a water tub with water hiacynth near the hives and at least some of the bees use it.  Testing would certainly answer some of the questions.  May do it this year if the cost is not prohibitive.

Waldemar

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