University vice-chancellor Harlene Hayne and several former association presidents and other life members were among more than 30 people at the 11.30am ceremony at the University Union lawn.
Helen Jamieson, who was visiting from Germany, was among the former presidents attending.
Association president Jack Manning welcomed participants, former president Paul Gourlie took a photo of the group, and academic John Broughton gave a Maori blessing.
As the kowhai tree was planted, several participants added soil to its base.
Retired university chaplain Rev Greg Hughson was among the many association life members attending.
The gathering then moved to the nearby association rooms, where Mr Manning formally conferred life membership on Richard Good, and a birthday cake was cut.
Mr Good was for nearly three decades a broadcaster at Radio One 91FM, and the host of the Sunday morning show Jazz Junction.
Mr Manning said the association had grown from small beginnings to employ about 90 full and part-time staff, and now owned several buildings, including the Clubs and Societies Building.
Service for students and advocacy on their behalf remained crucial for the association, although the issues and challenges had changed over the years, including during this year’s Covid-19 lockdown.
The association’s success in helping persuade the university to increase its proposed rebate from $120 to $200 for students who usually lived in halls of residence but stayed elsewhere during the lockdown showed that it remained an effective advocate for students, he said.
