Mary Dedecker

A black and what photo of a woman sitting on a rock in desert landscape
Dedecker in 1993.

Botanist & Environmentalist


Mary Dedecker was a local botanist and environmental expert, credited with discovering six new plant species in the Eastern Sierra Nevada and northern Mojave desert region.

Mary Dedecker was born Mary Caroline Foster in Oklahoma in 1909 but moved to Southern California when she was young. She attended Van Nuys High School and spent a year at UCLA. In 1935, Dedecker moved with her husband and two daughters to the town of Independence, located just west of Death Valley at the base of the Sierra Nevada. The family spent much of their time hiking and exploring this unique region of California.

Dedecker discovered her passion for botany in 1967 after meeting Mark Kerr, a botanist who focused on Paiute uses of native plants. Working with Kerr inspired Dedecker to become a self-trained botanist, and she proved to be a quick study. She collected and sent over 6,000 samples to academic institutions for identification and discovered six new plant species, three of which are now named after her (Dedeckera eurekensis, Lupinus dedeckerae, and Trifolium dedeckerae). Additionally Dedeckera Canyon in the northwest part of Death Valley National Park was named in honor of Mary’s work and many discoveries.

Mary Dedecker’s expertise did not stop at the borders of Death Valley National Park. She quickly became the expert on plant life of the Eastern Sierra and northern Mojave. Her passion for this region extended beyond plant life; she wrote several books on mining and daily life for men and women in the Death Valley area. She detailed the importance of desert landscapes and histories for the rest of her life through writing, political activism, and passionate testimonies.

Despite finding her love for plant life later in her life, Mary Dedecker devoted nearly 50 years to learning about the flora that dwell in Death Valley. Her extensive knowledge and passion were crucial to the effort to pass the California Desert Protection Act in 1994, which established Death Valley National Park and stands as a monumental environmental conservation effort. Her writings continue to serve contemporary researchers and botanists of the native plant life, and her love for this vast and beautiful desert landscape lives on.

Last updated: October 12, 2020

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P.O. Box 579
Death Valley , CA 92328


760 786-3200

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