Larry if you're looking for scientific articles about heat stress in monocots try turf/grasses, such as the technique of "syringing" which sounds rather like what you found for corn. I think I read a while back that fans may work better than syringing (sometimes used on golf greens) but I can't see anyone setting up a large scale fan system for daylilies! Something like a quarter of all flowering plants are monocots but turf has been particularly studied because of its use in various sports. I guess because of the volume of corn grown it would have been much studied too and maybe in this context annual vs perennial doesn't make as much difference.
One thing that would be interesting to look at scientifically is whether the same plants that go summer dormant (meaning dying back as well as not growing) actually do go dormant in other summers. By that I mean in the technical, not daylily, use of dormant which doesn't require that the foliage dies back, it just means that the plant is not growing at that time. Could it be that they always go dormant (stop growing) in summer but only extreme circumstances cause the leaves to actually die?
