There is anecdotal evidence it exists in Missouri, but MODOC claims that there's no physical evidence. I seem to remember seeing it a few times up near Springfield, so I will look tomorrow when I go to town. I will probably walk the Frisco Highline Trail while my roommate shops. If there are seeds left, they're yours.
Want some yucca with them? I have Yucca Glauca, Joshua Tree, and Yucca Arkansana. Really easy to grow, but some don't like the roots being disturbed, so it's best to transplant the entire root ball, or use biodegradable pots and plant the whole thing. But out of the species I have, the Joshua Tree is the only really sensitive one.
I walked about 3 miles yesterday down a ridgeline trail and didn't spot any prickly ashtrees. I'll keep looking. I'm starting to believe that they aren't around here after all.
Wow, thank you Thomas!!! No worries if you can't find them. I'll find some somewhere
It's interesting how they have stayed outside of Maine. I mean to address that in my forest garden.
Try Etsy or Ebay. I get most of my seeds and cactus cuttings from them or Treeseedman.com. He gas really good stuff and amazing prices. If you use Ebay or Etsy, just make sure you use the filters and only shop in the US, or you may get stuff confiscated depending on where it's from. Good hunting.