>     Carbaryl is deadly to bees. They can pick it up on their feet and
>     carry it back to the colony. The XLR formulation is the lesser of two
>     evils. It will kill some bees but usually not the colony. Unlike
>     purethroid insecticides which kill bees in the field before they get
>     back home, a field bee can transport carbaryl home before dying. This
>     can result in larval death within the colony. If a colony is
>     inadvertantly sprayed with carbaryl that colony is likely to die as a
>     result. Other alternatives include any of the pyrethroid insecticides
>     labelled or malathion or methoxychlor or a mix of malathion and
>     methoxychlor. Any of these products should be sprayed in the evening
>     after the bees leave the field. This gives the insecticide time to
>     leave the field. You did not mention the crop so I am not sure about
>     specific insecticide recommendations.
>                                Ray Nabors
 
Thanks for the reply Ray.  The crop is blueberries.  The pest is flea
beetles.  My specific concerns are how long to wait after the crop has been
sprayed with sevin xlr plus before moving bees into the field (the
manufacturer says as soon as the spray has dried, can I believe them?).
Supposedly the stuff has a sticker which makes it difficult for the bees to
pick up (but as you say I could see them getting it on their feet).  If a
grower wants to spray with sevin xlr plus and avoids the colonies, sprays in
the evening, and I put a tarpaulin over the colonies and leave in on for a
while in the morning until I feel sure the spray has dried, how safe do you
think this would be?  I could suggest another spray to this grower but he
might be sceptical.  He sprayed one field with methoxychlor before I put the
bees in, and apparently it did not do much to the flea beetles.
Regards,  Stan