In the Japanese martial arts of using the stick we have three primary lengths:
Bo- 6 feet.
Jo- 5 feet.
Hanbo- 3 feet.
Generally speaking the idea behind the stick is to use the distance of it, when combined with footwork, gives a greater reach. I keep my training partner at X feet away with the stick using methods of striking, receiving, and postures.
When we move to the jo, from the bo, we lose a foot in length which while doesn’t or may not seem like much, does change the feeling and tempo of the stick.
Movement wise, the jo is much more nimble, and quicker, and by dropping a foot in length one can still engage at a distance, yet manipulate it in some new ways that just are not practical with the bo.
Once certainly could do *bo* techniques with the *jo* but they would not be taking advantage of the special properties of the jo.