 Popple Grove Township was named for its groves of poplar.According to the United States Census Bureau, the township has a total area of 37.5 square miles (97.0 km²), of which 37.3 square miles (96.6 km²) of it is land and 0.1 square miles (0.3 km²) of it (0.35%) is water.As of the census of 2000, there were 154 people, 53 households, and 41 families residing in the township.