Sharon,
Aphids are very bad this season over here. I suspect what you are seeing is the shed skins of aphids. If they are primarily down in the middle of the fans. Look deeper between the leaves to see if the aphids are there. There are several good recommendations on how to treat them on the AHS pages, if you need them.
Ed

Here is a link that might be useful: Aphids page, AHS

I looked, I don't think it's aphids.

Sharon

Spider mites?

Found this link that may be useful. It mentions gall midge as a tiny white insect. Vickie

Here is a link that might be useful: Daylily Pests

I would hope that the gall midge hasn't yet spread to Louisiana!! They have been spotted in Europe and in Western Canada, but hopefully not all over the mainland US * yet . I'm thinking mealybugs. If you google mealybugs, you can find pictures. They have that white look you describe.

I really can't tell what it is, I am going to get some insecticidal soap and spray them Monday after this blasted rain stops.

Sharon