Too Hot for Powdered Sugar ?

[Aisha]

My new hive is just 3 weeks old. I started noticing some curly wings on 3-4 bees each day recently. I see an occasional varroa mite on these, esp. drones, so I guess it's time to dust.

I read on Michael Bush's site that powdered sugar should *not* be dusted when it's too hot outside or it can kill the bees. Here's the quote:

"It is also very temperature sensitive. Too cold and the mites don't fall. Too hot and the bees die." -- http://www.bushfarms.com/beespests.htm#varroa

What is too hot? Should I do it in the evening when it's cooler?

FYI: Right now it's 92*F with high humidity. Next week will be even hotter and drier.

I have put a sticky sheet beneath my sbb to get a 24 hour baseline count.

Until now my sbb has been open air, but 200 bees have been bearding under there every day for weeks. I had to brush them all off today to put the sticky board in.

Thanks!

[Ishi]

96 to 100F Humidity 12% no problem with dusting.

[Michael Bush]

>"It is also very temperature sensitive. Too cold and the mites don't fall. Too hot and the bees die." -- http://www.bushfarms.com/beespests.htm#varroa

>What is too hot? Should I do it in the evening when it's cooler?

That was based on presentations by Nick Aliano on his research on powdered sugar for Varroa. His method was to run all the bees out of the hive into a cage and treat them there. His results were that very few mites fell if it wasn't fairly warm and crowded, but if it was too warm and crowded the bees overheated, regurgitated honey all over each other and died.

I would guess that in a hive with just spilling it on the bees, it shouldn't cause any excessive heat.

[Aisha]

Thanks Michael. I feel more confident giving it a try in the summer heat.

The good news is I only had 27 mites in 24 hours.

[Laurence Hope]

I am currently doing mine at 100 or so degrees without any problems.