[2] After his retirement from the USDA, Archer was appointed Research Associate in the Department of Botany, National Museum of Natural History (NMNH).
His academic interests focused on botany, mycology, plant pathology, bacteriology, physical chemistry, entomology, ornithology, genetics, and English composition.
He was unemployed during the Great Depression, eventually finding a position at a brewery in Foggy Bottom before starting his career as an employee of the United States government.
The gallon pot that geysered on the electric unit in the Herbarium quarters at Beltsville, Maryland, before its removal to the National Arboretum, reeked the entire building's atmosphere with its searing contents.
He was stationed in Belém at the Brazilian Research Institute in the Office of Foreign Agriculture relations, and served as a plant taxonomist and herbarium curator at the United States National Arboretum.