Shortest songs I've got on hand:

Fiddle Tune - Flatt and Scruggs - At Carnegie Hall! - 45 sec
Short and Sweet - Hylo Brown - Hylo Brown Sings the Blues - 52 sec
Lonely Road - Klaudt Indian Family - Gospel Warhoops - 1 min 5 sec
Shortening Bread - Flatt and Scruggs - Live TV - 1 min 10 sec
Dooley - Andy Griffith - The Andy Griffith Show - 1 min 16 sec
You Can't Stop Me From Dreaming - Flatt and Scruggs - At Carnegie Hall! - 1 min 17 sec
Old Time Religion - Carl Story - Bluegrass, Gospel, And Mountain Music: 1942-1959 - 1 min 19 sec
Coal Creek March - Pete Seeger - Banjo Tunes and Songs - 1 min 25 sec
The Tie That Binds - Jim Greer - Stars of the WWVA Jamboree - 1 min 27 sec
Cripple Creek - Stringbean - Live TV - 1 min 29 sec


I have another 36 songs between 1:30 at 2:00, but I don't have time to post all of them. Plus, after 1:45 or so, they're really not that short anymore.