To be truthful, my husband grabbed the wrong seed bag at Southern States and inadvertently put in feed corn. UGH. That - combined with our heat wave - made it not only inedible but also nasty to look at. So . . . we left it in. Our original intent had been to harvest the corn and then let them in while the stalks were there to work on bugs, fertilize, pre-till, so that we could then remove the stalks and prepare the bed for fall planting. Figured the stalks would give the girls shade and they do. Plus, the gal's just love digging at the base of each stalk, working up bugs, having a grand old time!
To answer your question - the girls aren't eating the stalks but they're jumping up against them and pushing on them to get to aphids, bugs, that are on the stalks. The whole corn patch is leaning now!