DFStoneJr wrote:

Leaves are curling inward toward the middle from both sides on my "Summer
Snow" roses. This has happened before, and floral production has been
lousy. I'm determined to find out what it is this year and, more
importantly, take steps to correct it. Any thoughts, ideas or knowledge
here?

Dillard,

The only time I have seen such inward curling of rose leaves is when
powdery mildew is present. Do you see this scourge on your rose? Here
is a picture to help with the identification:

http://asparagin.cenargen.embrapa.br....pl?rose:16043

There is apparently a viral disease that causes rose leaves to curl
downward, but what you are describing is an inward curl, so I doubt that
this is the same.

Here are a couple of web sites which might help you with both the
identification and eradication of what you are seeing on this rose:

http://www.ipm.ucdavis.edu/PMG/r280112611.html
http://www.markw.com/diseases.htm

Good luck.

--
Radika
California
USDA 9 / Sunset 15