Cats1 - Thanks for posting that photo! If it is leaf streak, then that is a good shot of it!
Sue - Wow! You've obviously been studying daylily rust as well as leaf streak. Thanks for sharing all that wonderful info and some links to read. I'm going to throw a possible curve ball here on some of that information. I have 2 full sun beds and 2 partial shade beds. All have had rain and have irrigation. And we do have a lot of humidity here during the evening hours, so all the daylilies are exposed to dew on them overnight when the temps drop down and there is no sun light. The shaded beds do have some rust, but not nearly as much as the full sun beds. Any ideas why that might be? That goes against what the studies say?