My deciduous daylilies recently put forth some beautiful fresh
foliage. But today I noticed that they're being ravaged by something!
The leaves look torn up, with ragged edges. Usually daylillies, in
my experience, are pretty pest free, so I'm puzzled as to what's
attacking them this spring. Could this have been the lawn guy with a
careless weedwhacker? Or is this some insect at work?

Here's a photo of the carnage:
http://www.inhouzemusic.com/daylilly.html