Crab Grass.

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.
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You need to apply a pre-emergent in the spring. Don't know about your area but rule of thumb here is just before forsythias bloom. Crabgrass dies in the winter but next years crop of seeds are already in your lawn.
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Lawns don't spread and establish naturally, unless you let them go to seed. Clump type grasses, eg tall fescue, is one plant. The plant can grow larger if it has empty space next to it, but it isn't going to grow from a 6" plant to fill your back lawn. Bluegrass can spread via rhizomes but it would take forever to fill a backyard that is bare.
I'd also consider what exactly you have there. You know you can't make a silk pursue out of a sow's ear, right? If it's some crap grass, poor texture, poor color, poor wear tolerance, etc, would you want it to be your lawn?

Why? If cost is an issue, you could re-seed inexpensively. Better and cheaper to do it right once, instead of screwing around. Depending on the soil condition, it could be as simple as killing it off with Roundup, core aerating, then using an over-seeder to put down the new seed.

You sure it's crabgrass? Crabgrass grows in the heat of summer and dies off in early Fall. In Portland you have temps in the 30s at night no? I'm in Coastal NJ where it's barely gotten down to freezing and all the crabgrass has been dead since mid Oct.

Seems you're hell bent on doing everything the hard way. Let's say you have a 6000 sq ft lawn. In late Aug/early Sept I would have:
Sprayed the crap that is there with Roundup. 1 hour Wait about 10 days until it;s all dead, mow short 1 hour Rake up the major part of the debris 3 hours Rent a core aerator 3 hours Rent an overseeder 3 hours
Cost: $250
With an appropriate, quality grass seed, you'd be looking at a half way decent lawn now and a mighty fine one by summer.

It's been in the low 40s, or 30s at night for how long by you? Crabgrass?

You're learning the big problem with pulling weeds. It opens up the soil and allows a spot for more weeds to get established. Forget about doing anything at this point. Except maybe testing the soil and liming if necessary,
Depending on what you have there now and if you can tolerate it another season, I'd either get through another year and re-seed in the fall, or else re-seed in spring. Fall is by far the best time. But then you're in OR with plenty of rain and more moderate summer, right? Main problem with spring seeding for you will be competition from weeds. But if you keep after it, it can be done.
As Frank suggested, the best solution with crabgrass is to put down a pre-emergent in Spring. It's usually sold together with fertilizer. BUT, if you do seeding in the spring, make sure you use one of the pre-emergent products, eg Tupersan, that is suitable for seeding, new grass, etc. The conventional, most common ones can't be used with new seeding. Another reason why seeding in fall is better.

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Well, all I know is that as I clear out the wood chips and pine needels and get down to dirt, grass will start growing. It may not start immiediatly, but this summer I had less bare dirt and more grass.
I have to point out that in some areas I did sow some grass seed. But not all. Some of the areas where I did not sow are comming up grass. It starts out as a fairly even layer of small blades. They then grow to slowly fill out the area.

That's the millon $$ question. I'm no expert. But I can tell you that I have two types of grass in my lawn. The majority of it is a fine Blue Grass type of grass. Then there is this course textured grass. It looks a lot like Crab Grass. But it could be Zoyza or Burmuda for all I know.

Well, parts of the lawn are doing quite well. Why mess with that? It's just this one area that is needing work. There is hardly anything to kill right now. So I just clear out the pine needels and the wood chips. If something starts growing (and some times it does) So be it. But if I have my doubts, I'll sow some seed.

I'm beginning to have my doubts. We have had several nights (esp. in the last week) of temps at or near freezing. But the "Crab Grass" is still alive. So I'm having my doubts.

Well, it's not 6000 sqft. And most of it is in good shape. It's the part that used to be the dog run, and the part that is under the pine trees (neighbors trees that overhang my lot) and a few other small patches that need work.

Most of what is there is not crap. And the parts that need work don't have grass already. Although I could roundup the patches of course "Crab Grass" if that's the best way to go.

Then figure out how to dispose of them.

Yard is small enough to do this by hand.

Did that already. and put down Scotts Winter care. It helped bunches.

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Yeah, volunteer grass of unknown type will grow. As will whatever the crap is that you think is crabgrass and other weeds. If you want that for a lawn and are willing to wait many seasons, then that approach will work. Why not just clear out all the wood chips and renovate it the right way?

Crabgrass looks very different from either of those grasses. Look at some online pics. It's called crabgrass for a reason.

If parts are OK and you are happy with the quality of the grass that is there, then don't mess with it. I was addressing the area that you're having the problems with. If that's half of a lawn, then I'd still kill off and renovate the whole thing so it's one uniform lawn.

And how's that approach working? You remind me of a friend. He asks for advice and people give him 10 suggestions. He immediately comes up with reasons why he can't do any of them and continues on his own way.

If you had killed off all of what is there in late Aug and re-seeded in Sept that crap would not be there now

If those areas don't have grass, why are you asking how to deal with crabgrass? Just spray it with Roundup and it will kill it whatever it is.

You remind me of a friend. He asks for advice and people give him 10 suggestions. He immediately comes up with reasons why he can't do any of them and continues on his way.

Then why haven't you done it?

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Well, The wood chips and pine needles are mostly gone by now. It's all based on how fast the county can haul them away. I have a 90 Gallon lawn waste tip cart that gets picked up every other week. That limits the rate ot which I can remove them. Yeah, I know, there are faster ways of getting rid of the stuff.
For the most part I have been happy with what has been growing. It's just in the last month that I noticed the other grass that I thought was Crab Grass. There have been weeds, but I have been able to control them with Weed-b-gone or by pulling them up.

D'oh! Google images. Of course! <applies palm of hand to forehead>.

The part that needs work is only about 25% of the lawn. I don't want to make this a bigger project then necessary.

Reasonably good. Like I said, this was a recent (relitivly) purchas and there are many things that need doing around here. The lawn is a low to medium priority. For the first season I was just concerned with controling the weeds. That allowed the northwest and west areas of the lawn to florish. I left the pine needles and wood chips on the ground as mulch to help keep the weeds back. At the end of last season, I raked the pine needles (from two trees that overhang the NE corner) into a pile under the trees. And also raked up the wood chips. Then started the slow process (mentioned above) of disposing of the debris. No rush on that since interior renovations and repairs were going on.
This, of course is all background. I have given thought to your suggestions. But, as I pointed out, the lawn has not been the highest priority of all the projects that are competeing for my attention. But a couple of points: - I dont want to Roundup the entire lawn since I'm happy with the bigger part of it. - I will selectivly Roundup on the patches of "Crap Grass", and reseed. - FWIW: I didn't know that Roundup was appropriat for laws. I though it would permenently poision the soil. - With most of the house repairs and renovations done, the lawn will be a higher priority this next season.

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That's true. But I wasn't realy paying attention. Most of the lawn looks pretty good. It's just since October that I noticed this area of crappy grass and the other few patches. It's really not large enough to warrent killing the whole lawn. I just don't want ot to spread. Selective use of Roundup is warrented.

And he's supposed to do what? follow all 10 suggestions? Look. I've been at pains to point out that I am happy with most of the lawn. The part I'm working on is only about 25% of the lawn. There is no need to expand the project out to include the entire lawn, which I'm already happy with. Further, the problem areas are only about 10% of the part I'm working on. Again, no need to nuke everything over that. I can see selective use of roundup on the few trouble areas though.

As I said above. Other higher priority projects.

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Just make sure it's the regular Roundup, not extended duration type. You can also use any glyphosate based herbicide, which is what is in Roundup. You can seed a week after application.
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Awesome. Thanks,
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