Analysis for every piece of ground is different, but here is a pretty general typical example:
(40) Acres at $6,000 / acre = $240,000
Cash rent at $150/acre = $6,000 annual income
Less annual property taxes +/- $1,500
Net annual income $4,500
Just under a 2% return.
If crop prices run back up again, income can get a little better.
It's a bit better than what you can get out of a CD, and you would hope to have a little gain on it when you sell.
Won't work borrowing money, obviously.
As a hunter, I always try to pick up stuff that has a little hunt-able ground too, which is a pretty nice side benefit.