Seed stratification

For newbies like myself, I find seed stratification and germination to be a complex subject. I can't telll which species require cold stratification and which need to be sown right away. Is there a rule of thimbto follow? I tried applying what seemed to be a "common sense" approach to it, but I don't know if it matches up with reality. Is it a general truism that plants that go through dormancy / colder tolerance plants to produce seeds that require cold strtification? Conversely, would it also be true that the warmer climate plants don't require stratification and thus should be sown as soon as possible?

I would say that is generally true. My own protocol is simply to keep all of my seeds in cold storage until I use them. Germination of temperate species seed is higher with a few snap freezes over the winter.

I to store all my extra seeds in the cold, but the temperates always get the cold treatment, while the tropical I sometimes immediately germinate.

Thanks, that is very helpful. We newer folks don't always know to handle the seed SASES when they come. It's worse than trying to determine dormancy / slowing down. Of course having a book handy, now, makes a big difference!

What does the ICPS seedbank do with received seeds?