Just clean the tread where it touches the road. Any solvent, even gas. Or probably just soap & water. There is usually a film of protectant on new tires.
If you just hope the road wear will scuff/clean the tread surfaces...it will. But you will never know how well they are cleaned or when or if the extreme edges are clean at all.
Run through some un-seen moisture with side-treads still coated with slick-um and you will quickly be sliding backwards on your arse!
Just pay attention to the new tires for 50 or so, gently working up the side-tread to scuff them a little.
You may not plan to ever ride with a lot of lean angle, but you have to be prepared to swerve to miss the sand in the corner, or the old lady who hot-foots her walker right into your path!
Now, that's all pavement.
If you're blastin' head-long into the trails...fuggetaboutit!