Some background: So I bought this house two summers ago. When I moved in it had been empty for over 6 months. The lawn was a mess. There were weeds growing that were taller than my 7 year old son. My wife and I spent the better part of 3 days just pulling weeds. When the lawn came into it's own, there was a lot of dirt. The back part of the lawn behind the house was used as a dog run and was covered with wood chips and pine needles. A huge (and ongoing) effort is going into raking and disposing of pine needles and wood chips. I've managed to regain about 2/3rds of my back yard.
I have been trying to encourage the lawn to establish and spread naturally. I don't want to tear it up and re-sod. So I have been happy to see any grass growing. But now I see that I have crab grass in my developing lawn. ARrrggg! A bunch of it was next to a part that I had re-seeded this summer and the crab grass was invading the new grass. So I spant an hour yesterday with a cultivator hoe digging into the crab grass patch and pulling it up along with it's long stringy roots. Several of those roots ran into the patch of new grass and came up with sveral tufts of crab grass attached. I don't mind tearing up this patch of crab grass since there appears to be no good grass in here. But I also see that there are patches of mixed good/crab grass around the lawn.
What I wonder is: Should I try to uproot the crab grass in these mixed patches? Or would it be better to just sprey it down with crab crass killer?
Also; It is probably too late in the season to think about reseeding the bare patch where I uprooted the crab grass. Would it be a good idea to mulch the patch with leaves for the winter to keep the weeds out?
Locational info: I live in Portland, OR and we are going into a dry cool spell. Looks like no rain in the forecast for the next few days.