I'm not sure I understand your post. It almost seems as if you are saying that nodes are only underground. Could you clarify what you are really asking...or thinking?

I tried tracing the diseased branch to the node(a swelling that forms at the connection of a branch to the stem)but found that it was part of one of the stems and the swelling was at the point where the roots appear I did find several internodes present should I prune their to promote a new branch to grow?also another diseased tip is part of another stem that has a branch at the bottom should I again prune at the internode