Actually, the last time I looked into it, if you grow 2 acres of corn and 1 acre of soy, and feed it to chickens, you get out a similar number of calories (and more protein?) as 3 acres of soy.
Soy is pretty good, but corn is insane.
Soy is pretty good, but corn is insane.
When you feed those 36M calories to chickens, you get back 12M calories of chicken, which is actually less than 6 x 3 = 18M calories for the soybeans, so I'm misremembering something (maybe it's just an equivalent amount of protein? maybe chicken feed is a 3:1 corn:soy ratio?) or was just wrong.