i just did on my current grow. i had three of five males, so i yanked the males out with whatever soil clung to the roots, then dumped the soil in to a black trash bag, pulled out whatever roots were remaining (mostly the bigpeices) and then got as much air out of the bag as i could to keep the chances of mold down. and its in my basement right now nice and cool so the soil doesnt dry out too much.
i just recently reused some of it to top of my pots. i dont see the harm in it because i would think the roots remaing would just degrade and basically compost. anyone else do this?