The Yellowstone Paleontological Survey.
Santucci,V.L. (1998) The Yellowstone Paleontological Survey. The Yellowstone Paleontological Survey Vol. 98 # 1 P. 1- 51
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Genus Species Country(Region) From To
Picea Picea engelmannii Wyoming Quaternary
Pinaceae Pinaceae sp Wyoming Eocene
Pinus Pinus albicaulis Wyoming Quaternary
Pinus Pinus contorta Wyoming Quaternary
Pinus Pinus flexilis Wyoming Quaternary
Pinus Pinus ponderosa Wyoming Quaternary
Planera Planera sp Wyoming Eocene
Platanaceae Platanaceae sp Wyoming Eocene
Podocarpaceae Podocarpaceae sp Wyoming Eocene
Podocarpus Podocarpus sp Wyoming Eocene
Polemoniaceae Polemoniaceae sp Wyoming Quaternary
Polemonium Polemonium sp Wyoming Quaternary
Polygonaceae Polygonaceae sp Wyoming Eocene
Polypodiaceae Polypodiaceae sp Wyoming Eocene
Populus Populus balsamoides Wyoming Quaternary
Populus Populus sp Wyoming Quaternary
Populus Populus trichocarpa Wyoming Quaternary