I ran my subsoiler through my hayfield/future pasture this early spring, after the spring rains subsided. Went down 16"+. Slabs of sod literally pulled loose on top. This was the first I have ever known this ground to have something done to it like this, and we bought in 1969. Cattle was on it from 1970, to about '85. Just mowed after that, and hay made from it since 2000. To make an even bigger mess, with the drought, not enough rain to mellow things back out. It is just now settled back down some.
I bought a used 48" slit seeder late last fall with intentions of reseeding my pasture ground. Going to attempt it in mid, to late Sept. Hopefully the fall rains will get it started. You can rent those slit seeders at certain equipment dealers, and rental places. Locally here, they are $175.00 per day. That's why I jumped on the one I bought. Guy placed a Craigslist ad, and asked for offers. I was the only one that called in 2 months. Got it for $100.00, and is in decent shape, other than surface rust. We'll see how it works, then clean it up if it works out OK...