Answer: I'm not sure what might have munched the roots off your rose bush. Were any other plants affected in this same way? If so, you may have a population of squirrels, gophers, etc. If not, it could have been a wayward critter and it probably won't happen again. Just to be sure, you can line the planting hole with hardware cloth prior to putting a new rose bush in the same spot.
Best wishes with your new rose bush!
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