They are leaf rollers. Malatheon should do the trick. For me, they are worst in early spring when the plants are just getting started. I police the plants every evening. The worms are small and white, about 1/2" long. Once the plants get bigger the leaf rollers are'nt much of a problem for me.

For Southlatropical 9 - many thanks for your response. This is my first time to try cannas and I am not sure I will continue. At least now I know what the pests are and how to eliminate them; however, my plants are at least 4 1/2 to 5 1/2 feet high and I am still being bombarded by leaf rollers. Obviously here in Tennessee, they are much harder to control than in South Louisiana. By the way, I was born and raised in LA, near Lake Charles and DeRidder. Good to hear from you.

You can use trichogramma wasps (they don't sting us; they're microscopic) or BT, which is bacillus therengensis or something spelled sort of like that, if you don't want to use a toxin.

Hang in there;
cut off the misshapen leaves & let your cannas start over;
I bet there's still time for a new batch of leaves & maybe blooms this year.

& once you get rid of one generation of canna leaf rollers, it's much easier to control them in the future.

sylviatexas, I have noticed red wasps hanging out around my cannas on a regular basis. Do red wasps also hunt down leaf rollers? I saw one hovering slowly with what appeared to be a small caterpillar in it's grasp.