Hi Todd:
If the maple saplings are small enough to pull, then simply pull them out of the ground using your hands. You may need to wait until it rains or perhaps water the area to make pulling them easier.
If they are too large to pull by hand, then I suggest using a pruning saw or small chainsaw to cut them off at the base. The problem you'll eventually encounter when cutting young maples is that they resprout. To control the resprouts, you'll need to treat the freshly cut stumps with an effective herbicide.
Since maples are difficult to control and you need to contend with "off target" herbicide injury to your rose bushes, you may have to wait to treat the stumps during the dormant season.
One of the better herbicides for treating cut stump maple is (1) Triclopyr + 2,4-D (e.g., Crossbow). There are cheap "generic" formulations of Crossbow available at most farm stores.
Important: You must use caution with any herbicide, but especially when applying Crossbow since it can cause off-target damage to residual plants if applied during periods of high ambient temperatures (>75 degrees F). Therefore, it is best to treat the cut stumps during the dormant season (November - February).
Please check with your local Extension Forestry office for herbicide recommendations and regulations in your home state of Pennsylvania as certain herbicides may not be registered for use in your respective state.
Best of luck!