Photo by Paul Bergner: poison oak berries in winter. USA.

Branches in fruit. Marburg bot.g., Germany. Planted. 2006-10-02.

Smallish tree in fruit. Marburg bot.g., Germany. Planted. 2006-10-02.

Branch in seed. Marburg bot.g., Germany. Planted. 2006-10-02.

Bush with berries. Spring Canyon, Rockhound State Park, NM, US. Wild. 1998-05-01.

Closeup of berries. Spring Canyon, Rockhound State Park, NM, US. Wild. 1998-05-01.

Bush in flower. Chiricahuas, AZ, US. Wild. 1998-04-01.

Flowering branch. Chiricahuas, AZ, US. Wild. 1998-04-01.

Branches. Cibbet's Flat, CA, US Wild. 1998-03-01.

Bush in bud. Cibbet's Flat, CA, US Wild. 1998-03-01.

Classic texts: Journals: AJP 1881: The images.

Classic texts: Journals: AJP 1881: The images.

Classic texts: King's 1898: The Images.