Hello. I discovered your article too late to vote on, but enjoyed it thoroughly. My dad was a huge rock hound, and I used to walk the RR tracks, creeks and quarries with him, in the search for fossils. Was very enamored of crinoids and trilobites, though trilobites were a big find. Rather scarce. The RR used limestone for their tie-beds, which is full of fossils.

Your ?? about the fossil leaf/stem looks to me to be a Dawn redwood, possibly? That is what we found in Eastern Oregon at least. There are tons in the road cutbanks. That and Ginkos. And little fish. THOSE are a HUGELY fun find. Though seldom 'surfacing', PFI.
Thanks for sharing your awesome collection. Sorry I missed this, but just discovering you on here. We have a mutual friend, @donnadavisart. She it a hoot, and very talented. Cheers.