The idea for establishing Sigma Alpha at Oregon State University began in 1989, when an OSU Alpha Gamma Rho member visited the ΑΓΡ national headquarters. An Alpha Gamma Rho representative shared with him the idea of starting a Sigma Alpha chapter at OSU. The idea was then shared with Amber (Albertson) Holveck and Carol Magnus, both women very involved in the College of Agriculture at OSU. However, with thier busy schedules they had little time to pursue all of the details necesary to begin the chapter.

In the Fall of 1990, the idea to begin Sigma Alpha was again presented to a freshman student in the College of Agriculure. Sonya (Nyberg) Rhye had been through rush, and was very interested in a sorority with an emphasis on Agriculture. On October 5, 1991, the Sorority in Development process was completed and the organizaion became the Xi Chapter of Sigma Alpha.