[One day Yuri will be particularly rude and ask.

Okay, that's a valid question. Yuri is about as far from an economist as a person can get, it's a bit ridiculous for him to know this information.]

I read about agricultural practices in the different lands when I was younger. It was part of a bigger research module on horticulture. [He shrugs faintly.] When I learn something, it tends to stick.