[velikipop]

Tom,

I don't think you have anthracnose. The symptoms are black leaves with brown moist spots. From what I've read briefly it seems not to be a problem with roses.

What you might have is a spider mite infestation, overwatering or
as you thought, rust.

If it is mites you should see them on the underside of the plants. The remedy is to spray with water or insectcidal soap several times a day. If it's rust, then pick off all the affected leaves and spray the rose with sulphur spray or you might try your own baking soda and citrus spay. This is good for powdery mildew and black spot.
Mix:
4 teaspoons baking soda
1 teaspoon citrus oil
1 gallon of water.

I use baking soda to control fungal diseases on my tomatoes and grape vines.


Hopefully, your problem is not Rose mosaic, the symptoms for which are yellow irregular rings on leaves. In that case you should pull the rose and replace the soil.

Alex