Try ‘Rotenone.’ You can get in as a powder, but can make it into a spray. Don’t use it if it’s near water, though.
Use or spray when bees are least active at the end of the day. It’s approved for ‘organic gardening.’ We sell a ton of it at the garden center, though I’ve never had to use any chemicals of any kind in my organic garden, by design, so I don’t have personal experience with it. Sorry!
“Rotenone is a resinous compound produced by the roots of two members of the Leguminoceae family. Its common use is to control various leaf-feeding caterpillars, beetles, aphids and thrips on a wide variety of vegetables and small fruits. A slow-acting chemical, rotenone requires several days to kill most susceptible insects, but insect feeding stops shortly after exposure.
Rotenone is moderately toxic to most mammals, but is extremely toxic to fish. It’s widely used to poison “trash” fish during restocking projects. It has been assigned a CAUTION rating.”
http://www.coopext.colostate.edu/4DMG/VegFruit/organic.htm
You can still get rotenone dust?! I’m jealous! It’s the only thing that has worked for the last few years and they pulled it off the market. B/c there used to be so many big farms around here, most things are immune to sevin. :(