[2] Drew started working as an Assistant at the Gray Herbarium while attending Harvard.
At some point, Drew fell sick and Boyd was required to continue collecting plant specimens.
[3] He returned in 1934, taking professorships at the Cambridge School of Liberal Arts and at the American International College.
In 1943, Drew took part in the Cinchona Missions in Ecuador to help gather quinine to treat malaria in the armed forces during WWII.
[4] In 1945, he was hired as an associate professor in the department of botany and plant pathology at Michigan State College.