Charles Frank Drechsler (May 1, 1892 – February 5, 1986) was an American mycologist with 45 years of research with the United States Department of Agriculture.
He was raised by his parents Louis and Bertha Alvina Schultz Drechsler on a farm near the village of Butternut.
He earned his bachelor's degree in 1913, and went on to complete a Master of Science in plant pathology in 1914, producing a thesis on bacterial black rot of crucifers.
Drechsler then enrolled at Harvard University, working alongside noted mycologist Roland Thaxter.
He studied oomycete fungal plant diseases, many from the Genera Pythium, Phytophthora, and Aphanomyces, and identified several new species.
He published numerous papers (located in the Notable Works section below) on oomycetes that destroy nematodes, amoebae, and soil rhizopods.