Charles S. Parker Ph.D., a botanist and former Chairperson at Howard University, was a prolific plant collector. Over his career, Parker collected over 2,000 specimens which included over 900 different species. He collected all over North America, though most of his collections were concentrated in the Pacific Northwest, Mid-Atlantic, and Southeast regions of the United States. His collections in Idaho and Washington contributed greatly to the “Flora of Southeastern Washington and of Adjacent Idaho”. Notably, Harold St. John named two new taxa after Parker’s collections: Lathyrus parkeri H.St.John and Rosa spaldingii var. parkeri H.St.John. After moving to Washington, DC in the 1930s, Parker continued his collecting and expeditions, building the collection of specimens at the Howard University herbarium (HUDC). Our study documents Parker’s contributions to floristic work, and locations of the specimens of this pioneering Black botanist.