[3] By 1907, Landergin and his brother purchased 100,000 acres from the LS Ranch in Texas.
[3] When his brother died in 1923, Landergin became the sole proprietor of their ranching interests.
[4] Landergin served as the President of the First State Bank of Vega, Texas.
[3] Additionally, he served on the board of directors of the Glen Rio Oil Company.
[5] Landergin was elected as the Chairman of the Board of Trustees of Fairmount College, later known as Wichita State University, in 1914.
[6] By 1917, Landergin served on the board of directors of the Red Cross of Amarillo.
"[1] Landergin's mansion in Amarillo is listed on the National Register of Historic Places.