@matt pretty much never. Very few people I found actually grow corn. When they do, they grow popcorn which seems to be resistant for some odd reason. Maybe it just doesn’t have enough moisture. The only time I’ve found it was in a large organic corn field. It seems to grow best in large swaths of corn which is another reason why you don’t see it often
@matt it’s originally a grass. Which, I guess is a weed. Although there is much debate in the horticulture world I’ve what actually constitutes a weed. Given that corn has been domesticated and grown as a food crop for thousands of years most agree it is no longer a weed.
@Simon @Ted I guess to be “Carolus Clear” the plant I was asking about at the start is https://en.wikipedia.org/wiki/Dysphania_ambrosioides
@Simon Interesting, I didn't realize it was a corn weed; given its other names (pigweed, wormseed), I was hoping it'd be more common. Oh well!