Unknown leaf

[LincolnS]

Found an unknown leaf fossil in the central Washington Swauk formation. About 3.5 inches tip to base, 2.5 inches wide. 

[Micah]

Looks like Swauk and Chuckanut formation plant fossils haven’t been well studied/documented according to this paper... just looking at it as someone who enjoys a bit of plant IDing I’d say milkweed possibly. https://www.researchgate.net/publication/266138675_Washington's_fossil_forests

[LincolnS]

Hmmmm, it does look allot like milkweed. I was also considering some prehistoric locust, even though locust wasn’t native to Washington and is thought to have been brought here by settlers. Thanks. 

[Zenmaster6]

I personally live here and hunt at the chuckanut formation. I have found this plant too. Pls Pm me if you find out what it was. I had an idea but I forgot what exactly the genus name was

[Ruger9a]

Not sure if you've had time to check out the link above posted by Micah.  Because your specimen looks very much like Betula largie on page 16/17.  I may be wrong but it's worth checking out.

[piranha]

52 minutes ago, Ruger9a said:

Not sure if you've had time to check out the link above posted by Micah.  Because your specimen looks very much like Betula largie on page 16/17.  I may be wrong but it's worth checking out.

 

 

That is a Miocene species and the Swauk Formation is Eocene.

According to the experts this kind of pattern occurs in many different families, unfortunately an undescribed species.