I see no problems using rough cut lumber in hive construction provided the
wood is properly seasoned.
   I should expect that due to the woods rough texture the bees will tend to
propolize it a bit more than planed wood.
   If you desire to have your wood planed  the width of a hive body is well
within the range of just about every thickness planer out there and I am
certain you could trade a jar or two of honey with a hobby woodworker for the
job.
   Or  barring a planer a course grit belt on a belt sander would smooth the
wood
   In any case the bees won't care if the wood is planed or rough.
 
Beekeeper woodworker sharpener