Fossil leaves from Emerald Creek * Early Miocene of northern Idaho
Platanus and Zizyphoides
These photos show some examples of fossils that occur at the Middle Miocene Emerald Creek locality of northern Idaho. On the left is a sycamore leaf (Platanus; Platanaceae). These leaves can get to be quite large at this locality. 
On the right is Zizyphoides, the leaf of the Nordenskioldia plant, an extinct genus in the Trochodendraceae. Note the long petiole and lobed leaf margin. Zizyphoides-type leaves and Nordenskioldia are known from numerous Tertiary localities, including the Paleocene Almont flora of North Dakota and the middle Eocene flora of Republic, Washington..
Click for more fossils from this site: 
Liquidambar 1
Liquidambar 2
Manchester SR, PR Crane, DL Dilcher 1991 Nordenskioldia and Trochodendron fruits (Trochodendraceae) from the
     Miocene of northwestern North America.  Bot Gaz 152:357-368.