Xi Sigma Pi is a national honor society for students of forestry. Once a person has been initiated into the fraternity, they are a lifelong member of the national organization. The Iowa State University chapter of Xi Sigma Pi is Alpha Gamma, and includes faculty, staff, graduate students, and undergraduates within forestry and other departments.
"Xi Sigma Pi, Gamma Chapter,"
Ames Forester: Vol. 87
, Article 18.
Available at: https://lib.dr.iastate.edu/amesforester/vol87/iss1/18