As a town kid who is now an agronomist, my advice would be to start out in ag business but most importantly spend your summers
A) Interning for a company related to what you are considering doing
B) If you can't get an internship, try to get work at a local coop and learn how things work that way
Honestly, you might even want to work a summer at a coop before any internship no matter what.
That would allow you to kind of get into that world of farming and what goes into it, along with invaluable experience that comes along with everything that cooperatives do.
PM me if you have any other questions.
I'm going to ditto everything in this post. Internships helped a ton while in school. Try to vary your internships as well.
I went from two years of business into Agronomy my junior year and I would suggest doing it the other way around or at least keep it in the back of your mind and take some science classes while you're starting out. I transferred into ISU with every single elective credit I needed and spent my last 2.5 years taking nothing but required Agronomy classes to finish up. It made my last years a little less "fun" than they could have been.
I'm also going to be completely honest with you but don't let it keep you out. You are going to need to seperate yourself from the rest of the students if you intend on getting a decent job out of school in the Ag business. Ag companies just aren't hiring like they were even a couple years ago and I don't see that changing by the time you would be out. Most of the larger companies are laying off or on hiring freezes right now until the ag market rebounds and the larger companies are going to be where there are the majority of the finance type careers are in the ag world.