 John Davey came to Kent in 1881 as head grounds keeper at Standing Rock Cemetery , and planted several trees , landscaped the cemetery , and performed experiments on trees . In 1901 , he published his theories on tree surgery with his book The Tree Doctor , and later established the Davey Tree Expert Company in 1909 . The efforts of Davey and the presence of Davey Tree led to the establishment of " The Tree City " as a nickname for Kent , which is reflected in the city 's seal . The company continues to be headquartered in Kent and serves as the city 's largest private employer . 
