If DE is overused (like almost any 'natural' or 'organic' material) it has the potential to do more harm than good. DE can be especially detrimental to bees if applied (again - in excess) when the bees are active and dusted indiscriminately over a wide area or combined w/a liquid and sprayed. Although I fail to see why anyone would put DE in a liquid solution, since when DE gets wet, it compromises its effectiveness.

The above reasons are precisely why I prefer to apply it directly to the ground for cutworms. Or to combat cabbage loopers and wire worms, I put some in a very small, baby powder container. I can shake it on or poof it up under the leaves early in the morning or late at night after the bees have 'left the building'. Although, always check the leaves before dusting. Many bees sleep on the underside of the leaves of the last plant they visited that day and remain there to get an early breakfast the next morning.

Lindagee makes a good point in reminding us that even a good thing can be "not-so-good" if it's not used wisely.

I like the "poofing" idea with the baby powder container. I might use it around my cabbages. Not too many bees around them. I will try to pick off all the ladybugs and the larvae before I use it. I have a lot of wheelbugs/assassin bugs that I think are so fantastic, and I don't want to hurt them. Have to be careful picking them up because can give a really bad bite when aggitated. I had one assassin bug last summer who lived on the eggplants all season. I got to watch it grow from a tiny small orange/red nymph to adulthood. Really pretty neat.

I use BT in solution for cabbage loopers and tomato horn worms. I always use a respiratory mask during application.

If you use DE, I think it is essential to wear a filter mask because DE is a fine dust that will enter your lungs.

I have asthma and never use any kind of 'dust'.