I've actually had to address this recently with a female client, and I think it may actually be quite common. I was especially surprised because there is no significant different in side to side horizontal rowing strength.
You need to find your "mind muscle connection" with the lat. My client called it "sleeping lat syndrome" which I liked. Anyway, the first thing I worked on was actually having her feel the lat working - not "burning" but, working, or contracting. You need this before you do anything else.
What i've since used is in this blog posthttp://deansomerset.com/2012/06/08/the- ... ck-muscle/
But here's the videohttp://www.youtube.com/watch?feature=pl ... 2jd_dm0l2I
Called full kneeling pull downs. Remember the point in this recommendation isn't to smash the muscle from different angles and all that jazz. It's simply to find or groove the neural connection (mind-muscle-connection) in that sleeping lat. When you can contract it, you will be able to take that connection to every other exercise you want to do.
I'm sure some bodybuilder somwhere once said, "if you can't flex it, don't isolate it". Basically learn to flex it first.
Also with the above variation hip and neck/head position is crucial, and this makes perfect sense when you consider the multiple roles of the lats, especially as a core muscle and being the connection between hip and shoulder. You can also do one side at a time.
I also came across and have now used (with the same client) band-assisted-one arm pull ups. Discussed herehttp://www.negharfonooni.com/2011/12/23 ... t-pullups/
Basically one hand grabs pull up handle, the other grabs a resistance band which is choked round the pull up handle. This forces the non-banded side to do far more work. What we found was a major difference between sides. We done twice as many reps (as singles) on the weak side for 4 weeks. Afterwards the clients pullups went from 3 to 5 (female, remember). She was stuck at 3 pull ups for about 4 months before this (which is initially why I went back to drawing board and came across all this stuff. Oh, and realised that she was never really able to feel her lats working, especially on one side).
This was just before xmas and the same client just pulled 10KG over her previous PB for a double, and I have no doubt it's related - pulling with one lat can only hold you back!