I think your impression is not that dramatic. If I type in “agriculture” (first type the “”) in the Scopus sources:
https://www.scopus.com/sources.uri
I find 140 titles. Furthermore, you have 250 titles with “Food” in their name, a substantial number of them I presume include agriculture in their scope.
FYI, I enclosed the latest available list of Scopus titles (and discontinued titles).
Good luck with your search for a good platform for your work.