High Quality Content by WIKIPEDIA articles! Walnut Township is a township in Atchison County, Kansas, USA. AS of the 2000 census, its population was 427.WAlnut Township covers an area of 37.19 square miles (96.3 km2) and contains no incorporated settlements. ACcording to the USGS, it contains three cemeteries: Mount Gillian, Sapp and Summer.THe streams of Little Walnut Creek, Owl Creek and Walnut Creek run through this township.ATchison County (county code AT) is a county located in Northeast Kansas, in the Central United States. THe population was estimated to be 16745 in the year 2006. ITs county seat and most populous city is Atchison. THe county is named in honor of David Rice Atchison, a United States Senator from Missouri.