Watch the Joining the Upper Strings online guitar lesson by Jimmy Heffernan from Dobro Handbook

In this video, I'm going to marry the open D and B strings, which are in the open D major scale, with the closed first two strings from the bar D chord.

I'll then drop down to the open D major scale. Notice the flat 3 usage, F not F#. You can use blue notes in many ways outside of blues.