After 2 years, corn land is converted to soybean land, which is a legume type crop that can replace nutrients back into the grown, allowing them it to be used for corn growing in another season.

While I'm not vegetarian or vegan myself, I do center my diet largely around fruits, vegetables, whole grains and legumes.

welcome Oh small rOund green legume!

Beans and legumes have a very high caloric density for their volume which is why they were a standard item of every explorer/prospector/settler's kit.