Following Smith's graduation from the University of Nebraska in 1908, he was hired by Leland Ossian Howard to work at the USDA's Bureau of Entomology.
During this time Smith held several assignments including the Boll Weevil Eradication Program, the Gypsy Moth Parasite Laboratory in Melrose Highlands, Massachusetts, and a 1912 collaboration in Italy with Filippo Silvestri to identify a natural predator to the alfalfa weevil.
Eventually entomological research was stripped from the regulatory functions of the department and migrated to the University of California's College of Agriculture.
[10][11] Smith also established the Laboratory of Insect Pathology, appointing Edward Arthur Steinhaus as its first head.
[7] Smith has been considered "a renowned researcher in the biological control of citrus pests for the University of California.