Putting down a crabgrass preventer at the proper time for your area is key which will prevent this annual from growing and eventually rid you of the problem. Using something like Dimension that has longer protection range (opposed to short term on Halts) - also will kill baby seedlings.

Bayer and some other brands make a broadleaf weed killer that has crabgrass killer as well (Quiorlac?). However it is easily pulled as well - which helps remove the seeds which will sprout in the future years.

Fertiliizing and watering a week or two before you go weed hunting will help with killing them. Actively growing weeds are more easily killed.

More pictures at various angles/light will help with identifying.

Hybrid Fescue, very typical for So Cal. Here it is hybrid bermuda, a modest amount of St. Augustine, but last 20 years or so mostly Fescue.

hoovb is right. 90% chance it is Marathon dwarf fescue. It could be Marathon, Marathon II, or Marathon III. They get dwarfier with higher numbers.

Now, having said that, fescue is now and forever was, the wrong grass for the inland areas of SoCal. For me, inland means anywhere east of the 405 freeway or I-5 or the coastal range of mountains/foothills (whichever is closer to the beach). You are on the wrong side of I-5 and the coastal range. What you should have is either bermuda or St Augustine. Both of those are heat loving plants. Fescue is a cool weather grass which has been made to work only with daily watering. With either bermuda or St Aug you can get back to weekly watering even in the summer's hottest heat. With your drought you should be thinking of alternatives to fescue.

Now about this crabgrass you say you have...do you get seed heads every week or two? Are the blades pointy before you mow or are they more rounded? I'm asking because St Aug is often mistaken for crabgrass because they are both coarse bladed varieties of grass. St Aug has the rounded tips and no seed heads (very rare). All other grasses have pointy tips. If what you have is St Augustine and you are willing to go and grow that, then you don't have to do much of anything and it will take over. St Aug will dominate every other grassy plant with proper care (mulch mow at mower's highest setting, water once a week in the heat and much less often in the cool months, and fertilize 3x per year).

If you would like to change to bermuda, you can get bermuda seed very cheap or you can get bermuda sod. The sod is a much MUCH better variety of grass and should never be mixed with the seeded varieties. Seeded bermuda is the grass people complain about. Sodded bermuda is the grass everyone wishes they had. In SoCal they use sodded bermuda for golf greens. Bermuda takes a lot more care than St Aug if you want it to look nice, but it has the advantage of not dying when it goes completely without water for several months.

Thank you all for the help and advice. There are two patches of "crab grass". The photo shows the worst part of it. I picked up the house about three weeks ago, haven't watered it much (maybe two or three times). I was waiting to see which route to go and try to pull as many "weeds" out before going forward.

Yes, we are in a drought here but am ok with putting in time and work to get it looking better. Thanks again.

I do believe it is marathon grass. I live in an HOA community, my my neighbor informed me he has marathon grass.

I don't see any crabgrass in the picture, but the contrast is so high I can't see much of anything. Next time you take a picture, take it on a cloudy day. And if you want to try and identify the grass, take the picture from about 3 inches away, fully focused. If the plant has seed heads, that makes it much easier to ID.

Some people think they have crabgrass but don't. That's why the close up pix help.

What does your HOA require for lawn care? Do they enforce it? I just moved to a HOA area with no enforcement...apparently, because they have not said anything about my weeds. I'm counting on a good year next year for my small patch of St Aug grass to spread and start to take over. I'll probably patch in a few pieces to help. Anyway my HOA requires a "drought tolerant variety" of grass...whatever that is. Maybe that's why they haven't said anything about the weeds, because they definitely are drought tolerant.