Louis Charles Christopher Krieger (1873-1940) worked with David Griffiths at the Plant Introduction Garden in Chico, California. Griffiths was interested in the forage potential of prickly pear cacti (Opuntia spp.).
Krieger painted a large series of species and forms of Opuntia between 1912 and 1917 for Griffith’s studies. These paintings are in the collection of the Department of Botany, Smithsonian Institution. They are watercolor over light photographic prints (black and white). The attention to anatomical and morphological detail is exquisite.
Krieger painted many cacti, and his work is found in The Cactaceae, an important series by Britton and Rose. Though he is featured here for his Opuntia paintings, he is best known for his depictions of fungi.