Here you can compare the tree and brush cover of Palo Duro Canyon in 1937 and
in 2004.  The upper photo was taken by the CCC people in 1937 and is on display
in the Interpretive Center.  The lower photo I took in June 2004.
Palo Duro Canyon 1937

Palo Duro Canyon 2004

Notice the juniper growth not only on the Trujillo bench and mesa top, but also on
the canyon floor.