Stone bucket or stone fork.
They go by either name. You can get one with or without a grapple arm.
A couple of thoughts...
We have a number of food plots in terrain that has good soils, but is very rocky. I agree with the other poster who commented on the benefit of tilling because it brings up rocks
that will only pop up later anyway.
Here is the way that we did it.. Plow with a three bottom auto reset plow. It will bring up a lot of big rocks. Some will be big enough to pop the moldboard and cause the plow to reset. After plowing, go through with a grapple and pick out the large rocks. Then disc harrow. More rocks will come up. We usually run the tractor with a grapple or stone fork on the front with the plow or disc on back. Balances the machine & also provides for a way to pick up the rocks when the soil working attachments pull them up.
A regular grapple, or root grapple, will work well for really large rocks. But once the real big ones are out, you will need a stone fork or stone bucket. The stone fork has more tines that are closely spaced so that smaller rocks will not fall through. As mentioned earlier, these can be had with or without grapple arms.
Another way is to just use your bucket, pick the stones up by hand, throw them in the tractor bucket & haul them off. The only issue is that unless you plow and disc a lot of the buggers will lurk just below the surface. Also, one tends to lose one's sense of humor after the 15th or 20th bucket full of rocks that have been hand-loaded.
A root grapple or grapple with stone fork is one of the handiest attachments to have anyway. You can do all sorts of mischief with one. Great for hauling logs, brush, etc.
With regard to the box blade... Very helpful for leveling fields. But I would caution against using it to mine rocks. Yes, small rocks will get caught up in the box. But if you are running a box with scarifiers, too many large rocks can really abuse them, particularly if they get wedged in tightly. Yes, it will pull rocks up. An occasional large rock won't hurt, but a steady diet & box full of large rocks is not good.