I've never had voles attack my roses, and I have hundreds of roses (and probably hundreds of voles). Voles didn't bother with my daylilies either.
Voles did attack my junipers and killed just about all of them.

I guess they liked your Junipers or their location better. I planted one rose last fall in the new border to see what might happen and sure enough it was stripped to the crown and had to start all over this spring. It recovered slowly and is much smaller than it's companions.
I lost a apple tree 2 years ago when the buggers girdled it all the way around eating through the tree wrap under 3' of snow. Had to go to hardware cloth after that lose.
One winter I got on the snow shoes and compacted the snow around some areas to see if the technique worked keeping the voles out of those areas. It seemed to just because I didn't pack it down the following year and their nesting ground in the lawn was incredible!
linda