Flora Wambaugh Patterson (September 15, 1847–February 5, 1928)[1][2][3] was an American mycologist, and the first female plant pathologist hired by the United States Department of Agriculture.

[5][6] Patterson and her team discovered several species of disease-causing fungi that infect plants and pose a significant threat to agriculture.

[7] Although modern agricultural practices can now keep many of these threats in check, pathogenic fungi still have the ability to decimate crop yield with devastating consequences.

[9] Patterson received a master’s degree from Ohio Wesleyan Female College when she was 42, and after her husband’s death, she continued her studies at the University of Iowa, where her brother was a professor.

[4] During her almost thirty-year tenure at the USDA, Patterson increased the size of the U.S. National Fungus Collections by almost six-fold, from 19,000 to 115,000 reference specimens, making it the largest in the world.

[5] During her career, Patterson identified numerous new species of fungus, including those causing pineapple rot (Thielaviopsis paradoxa), peach leaf curl (Taphrina), and "witches' broom" on bamboo (Loculistroma bambusae), which was an entirely new genus.

[5] Together with Edith Katherine Cash and William Webster Diehl, she issued the exsiccata-like series Mycological Exchange of 1921 with specimens distributed by the USDA.

[5] As Mycologist in Charge, Patterson wrote a letter to David Fairchild at the Office of Seed and Plant Introduction explaining that nearly half of the trees were infected with crown gall disease, which causes abnormal, tumor-like growths on roots, trunks and branches.