hello Jade,
It sounds like we re in the same boat. I am looking for most of the same trees you have for the same reason. I am looking for lots of diverse tree seeds to plant my 150 acre woodlot. I hope to one day donate it as a public arboretum. I have none of the seeds ou are looking for but I have some northern red oak, and a few others. (mostly trees and shrubs) listed on my trade list. I live in Nova Scotia, so I would be willing to colect any seeds native to NS. What I really need are the trees you listed that you collected. except for the horse chestnut, which I have a lot of here. I hope we can help each other achieve our similar goals.
Charles Harvey
PS: e-mail me if you want to work something out

sounds good, i'll drop you an e-mail. I also picked up some green dissected/weeping Japanese maple seeds, those wont necessarily come true from seed, but in experience of growing them before, some showed that characteristic, and there were only that type growing in the area. I also have a birch, not sure which one, its very similar to yellow, but the buds aren't as pointy and the leaves are a bit fatter in shape.

do you have chinese elm?
I have lots, they germinate quickly easily and grow quickly. really nice tree

I have Northern Catalpa seeds. Anyone that wants some please send an sase. If you want them please let me know. Marg