A few days I just started to see leaves on my black rose that are partially eaten. I see no insects, flies, aphids, or worms on the rose. There are tiny black spots that look like ash (not alive). I've looked through my books but find nothing like this. Does any one know what could be causing this; disease or bug? I've included an image of one of the leaves (underside).
Thanks,
Mary
looks like damage caused by Fullers Rose Slug to me.
You got something there. We do have a lot of slugs including the Leopard ones. Time for the Diatomaceous earth and garlic spray.
Fuller's Rose Slug is not your typical slug so you should look it up. I don't think the Diatomaceous earth will help with them.
Rose Sawfly also skeletonizes leaves.
Japanese beetles can also do that though it is a little early yet.
Didn't see any beetles but I did see live green caterpillar. I have Pyola from Gardens Alive;
http://www.gardensalive.com/pyola-insect-spray/p/8101/
