So I got into cal poly slo for agriculture and now I want to know how slo compares to Davis in agriculture.
You need to be accepted to UC Davis before I would try to compare.
It really depends upon which major and what your career plans are with your major. What do you want to compare? Academics, location, student life, job opportunities/internships?
I highly recommend visiting both campuses before you decide. Cal Poly and UCD are very different in terms of weather, campus, etc…
I also agree with @Mom2BoysCA that visiting both campuses is a must to help solidify your decision.
Did you hear back from Davis?
@Cyla: UC Davis decisions are predicted to be out this Friday but not yet confirmed.
@Gumbymom thank you
Have you heard that slo has issues with students not getting into classes due to impacted classes?
Our older son is a freshman ME. He has not had any trouble getting into classes. For your fall quarter (and probably winter and spring, depending on major) the school will “block” you into your classes, i.e. schedule them for you. For S, he was in a psych class but wanted a different section with a smaller class and higher rated professor. He put himself on the waitlist, and attended both psych classes till he got into the one he wanted.
For the upcoming spring quarter, he was blocked into 12 units (math, physics, chem) but added himself to the waitlist for two other classes needed for his major. He got into both, and had the nice luxury of deciding which to drop. Whether you have difficulty getting classes is a complex issue. It depends on your major, how many AP credits you have (and not all APs get credit at Cal Poly, especially for engineering majors), your degree progress (how far along you are towards your degree), whether upper division students also want the class, etc.
Sometimes when people complain about getting classes at Cal Poly, I think it’s due to reasons other than space being available in the class. Some kids don’t want to wake up for a 7am lecture (our S had 7am classes M-F all Winter quarter). Some kids don’t want classes on Friday (S will have classes on Friday till 5pm next quarter.) Some want/don’t want a specific instructor. And because S arranged his spring classes so that his finals in June would end before Friday June 14th (same day as our younger son’s high school graduation), I think students also try to schedule classes so they don’t have finals on the last day.
So when someone complains that they can’t get classes at Cal Poly, take it with a grain of salt. Not to say that Cal Poly isn’t impacted or crowded (I feel sorry for this year’s sophomore class) or that many kids take 4 years + some extra quarters to graduate, but I think that’s pretty common for any public California university.
The 4-year graduation rate at Cal Poly isn’t great, its about 50%. I don’t know if that is due to trouble getting classes or just that kids don’t want to leave 
See https://ir.calpoly.edu/2017-persistence-rate-trends
But the 4 year rate was less that 25% for the entering class 15 years ago at Cal Poly so it has risen. I know that back in the day (eg 1980s) the 4-year rate at UCs was low since the schools were relatively inexpensive and nobody was in a hurry to enter the real world.
The CA publics have been pushing to get the echo boom thru faster, in part by enforcing minimum progress requirements. At UCLA the average time to degree was 11.8 registered quarters (excludes time off) for freshman entrants who graduated in 2017-18, so they’re getting a lot of kids out on time.
As a side note, you can find a lot of interesting info about many colleges in general and for the CA publics by looking for their “institutional reseach” or “academic planning” website. They often give stats such as gpa and SAT on entering students by major, average gpa by major and units completed, degrees awarded, etc.