Aphids

This is probably common sap-sucking insect pests (found on many plants) called Aphids. Its hard to be 100% positive because we can’t see the pest clearly enough in this photo, but they are a common pest of Rose, and when populations are high and they are developing thru their life cycle quickly, we see their shed skins stuck to the leaves like this (a result of their normal gradual metamorphosis from young nymph stages to adult). You’ll want to look for the green (usually, but they can also be yellow, black, and peach colored) insects on the undersides of the leaves and on developing flower buds. The good news is, they are pretty easy to control. The females reproduce live young (minatures of themselves) in multiple numbers, and without being fertilized by a male, so they can reproduce quickly in the right environment. As they suck out the sugary plant sap they also excrete it, which makes the leaves sticky. We recommend you control this population as soon as possible by either spraying off with a high pressure spray of water, (you may have to do this several times on consecutive days to get them under control), and/or pick off the most infested leaves. If they contine to re-populate you’ll need to keep up with them – wipe off by hand, use high pressure water spray, or use products like pesticidal soaps or horticultural oil. Be careful to follow the directions on all product labels. (The oil in particular can cause plant damage if applied incorrectly/under high temps and low moisture conditions). We’ve included a link with more info about Aphids and ways to control them.
http://www.ipm.ucdavis.edu/QT/aphidscard.html