Please Help: QED and QCD Feynman diagrams!

I am not a physisist.
I am assisting in the production of the play "QED" and I have a
question that I can't seem to find a satisfactory answer for:

At one point in the play, Feynman draws the "QED" diagram (that's what
the notes say) while discussing the way the "field doesn't interact
with itself, thus spreading everywhere" and then he draws the "QCD"
diagram, saying that fields in QCD also interact with themselves.

Can anybody help? What diagram would he be drawing?

Thank you very much!

Jo