From the Little Sandy Review, Issue 13:
The Minnesota Folk Song Society got off to an enthusiastic start with a Hootenanny that featured local talent. It was encouraging to see a 3 1/2 hour program that contained no youngsters performing commercial folkum. The acts were about equally divided among Bluegrass, Blues, and Old-Timey Hillbilly performers.
The magazine later reported that Bob Dylan made “a brief, but extremely telling, appearance at a University hootenanny,” so maybe it was this one.