"Okay. Fine. Whatever." wrote:
Since you were nice enough to answer my last question, may I ask you a
few more? I appear to have a serious case of black spot, and I'm
leery of using fungicides; I'm cancer-phobic and don't even like to
stand too close to the microwave oven. I bought some Rose Defense and
had hoped to use that, after stripping my rose bushes of leaves that
appear infected. Do you know if Rose Defense works? Is my concern
over the use of fungicides silly? Is there such thing as a "mild"
fungicide?

I seem to have had a bit of success with hydrogen peroxide, drugstore 3%
stuff diluted about 8:1 (the commercial-nursery variety is much stronger and
is supposed to be diluted 100:1). It's sold as a greenhouse disinfectant
that
can also be sprayed on live plants, and it's supposed to destroy fungal
spores
though not the fungi in plant tissue. I sprayed it lavishly on healthy and
sick
leaves alike and on leaf litter during a wet spell early this past summer,
every
few days for several weeks, and the black spot stopped spreading -- as far
as
I could tell: leaves infected with black spot died and fell off, but there
seemed
to be no further infestation for months. Did the peroxide really do this?
I'm not
certain. It was cheap, it seemed not to hurt my roses at all, and it could
hardly
be called toxic. I plan to try it again if the wet weather resumes and
black spot
comes with it; I stopped mostly because I thought it would trash my homebrew
deer repellent.

Supposedly it's no help to strip infected leaves -- or so say some pundits.
If
they're still photosynthesizing despite the infestation, removing them
simply
weakens the plant and doesn't do much to stop the fungus.

Your mileage may vary, and so on. Your pundits may say otherwise.

Mark.