Katherine Esau (3 April 1898 – 4 June 1997) was a German-American botanist.
She was born in Yekaterinoslav, Russian Empire (now Dnipropetrovsk, Ukraine) to a family of Mennonites of German descent. After the Revolution her family moved to Germany, and then to California, where she achieved her doctorate in 1931. She moved to the University of California, Santa Barbara in 1963, and worked there until 1992. She was the sixth woman elected to the National Academy of Sciences in 1957, and in 1989, President George Bush awarded Dr. Esau the National Medal of Science.
Esau was a pioneering plant anatomist--perhaps the greatest plant anatomist of the 20th century. Her books Plant Anatomy and Anatomy of Seed Plants have been key plant structural biology texts for the last four decades.
To read more about Katherine Esau, visit her page on Wikipedia.