There are several possibilities and if you send a photo I can be more accurate. Most common would be a caterpillar or worm that could leave behind the veins or the leaves like a skeleton. (Tiny green worms hide on the underside of leaf.) Control by hand picking in early morning or using a pesticide with Baccillus thuningiensis. If the holes are along the leaf margins and also the middle of the leaf look for a beetle. Most beetles cause only a bit of damage for a short time them fly away so you can wait it out unless you have the notorious Japanese beetle - a large beetle that does lots of damage to leaves and buds. Your local extension agent or nursery can advise you on control of Japanese beetles in your area - here in the NW we do not have Japanese beetles. If the holes are larger and irregular about the size of an eraser it could be tiny baby slugs or snails - especially after a rainy spell. Try checking at night with a flashlight for slugs or snails then use bait at base of rose bush. You can also remove all damaged leaves to instantly improve the looks and to try and find the culprit. Good luck, Marianne Binetti