paul,
i also agree that its poa.. instead of me putting down pre-M on labor day, i did the exact wrong thing and put down fertilizer. im shocked how profusely it grew in two weeks that it has choked out alot of the good kbg in a 1200sqft area and i thought it was the new kbg coming in until i realized its bunched and very light. this is crazy. there is so much bad info out there. the thing to do was to put down a pre-M before seeding, not just round-up. and then not fertilize. this poa i have is so everywhere that im in real trouble. when u pull this stuff, should i get some sort of weed puller so i dont pull the little kbg nearby? how do you do it?

Not sure why you repeatedly blame "bad info out there." It is standard practice to apply starter fertilizer when seeding and to continue to keep the new lawn well fertilized afterward. Not sure why you got fertilizer burn--perhaps over-application or you didn't water it in--but that is not typical, nor is it bad advice. It is also not typical to apply pre-emergent unless you had a pre-existing weed problem--in which case, you are fighting a hard battle to begin with. Seems like you just stumbled upon this grassy weed problem after-the-fact so certainly should not be blaming others for "bad info".

Having had my share of both poa annua and trivialis, I can say with high certainty that your grassy weed in question is not of the poa variety. I do not know what it is as I have never seen anything like that.

I think it's important to identify what weed you are talking about. Can you post followup daytime pictures? I've looked at some of the other grassy weeds (goosegrass, orchardgrass, barnyardgrass, etc) and your pics don't look like any of them. Also, poa annua will seed in fall but not nearly like what it does in spring. Certainly poa contamination of seed stock has been reported, but if you have a ton of it, I would more inclined to believe you had some before. I know Meleca had a poa problem before he renovated.

You pics don't seem to have the density of seedlings that I see with poa annua infestations. The leaves in your pics do not have these ripples that poa annua often has. The base of a poa plant don't have such thick looking stalks like your pic. The width of the leaves should resemble KBG. If it ends up being poa triv, I think you will have pretty good success with Certainty herbicide next year. If poa annua, be prepared for a fight lasting several years. In any case, I am sorry you had this problem--there is enough to worry about when renovating a lawn and it sucks when things go wrong.

"the thing to do was to put down a pre-M before seeding, not just round-up. and then not fertilize. "

If you use pre emergent before seeding, it will prevent your KBG from germinating as well. There are products that will prevent crabgrass but not KBG, but KBG and Poa annua are both Poa. I may be wrong, but I don't think there's a product that will stop poa annua from germinating and let poa pratensis (KBG) germinate.

The poa annua that germinated is probably from existing seeds in the lawn. What some people do in a complete renovation is to use the glyphosate, wait until it all dies, then start watering every day to get any existing seeds to germinate. Then hit it again with glyphosate.

its poa, it cant be anything else. i did everything i was supposed to do and have half a fricking lawn of it. this is nuts. im calling pawnee butte tomorrow to ask them how sod-quality could possibly be filled with so much poa seed. isn't the point of buying sod-quality seed and do a new lawn and spend all this time and money, so it ISNT contaminated ? that is borderline fraud if that is the case. i cut the grass yesterday by the way.
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When you say it's poa, I assume you mean poa annua, since the seeds you bought are also poa (poa pratensis). How do you know the weed seeds came with the seeds you purchased?

Did you kill all the grass, then water daily for a couple of weeks to get existing seeds to germinate and then kill everything again? If not, any and all weed seeds that were in your lawn when you killed the grass sprouted when the conditions were right. When you plant grass seeds and water to get them to germinate, the goal is to create conditions that are perfect for seeds to germinate. Unfortunately, there's no way to create conditions that are perfect for poa pratensis that are not also perfect conditions for poa annua, so if there were any poa annua seeds in the lawn when you started, they would germinate along with the KBG you wanted to grow.

Yup. Those pics are definitely poa annua. That much is very hard to deal with.

Re: Pawnee Buttes. I think it's impossible to lay blame on them. Even non-sod quality seed should not produce that kind of result. Any time you start from scratch, any seed that is in the soil can germinate. Most of the time, people do not realize that they have a poa annua problem. I sure didn't. Like you, I had some serious poa infestation after seeding that has taken several years just to reduce it to nuisance level. In any case, I hope your entire lawn isn't like your pictures. My feeling is, next spring, I would either kill or pull up as much poa as I could. When it seeds, look out! I would also suggest buying a bunch of plastic box planters and growing sod using sterile potting media to transplant into poa infested patches in the spring.

the amount of it suggests to me that it must have been in the seed, pawnee butte even sell the poa seeds. do you realize that i wasted two months and alot of money instead of simply getting sod? this is insane. so much for having an elite lawn

the strange thing is that there were several posters who swore it wasn't poa, thats why im so confused. does poa grow four inches in three weeks ? and how high does it grow? they keep producing white seedheads.. why aren't my kbg doing the same ?

I also did not think it was poa initially. However, your initial pics were taken at night with flash and in the fall, there are no trademark seedheads-up-the-wazoo. Poa annua germinates and establishes way faster than KBG--it will give PRG a run for it's money. It generally does not grow tall though. They are prolific seed producers--in the spring, heavily infested areas look almost all greyish-white because of all the seedheads. Elite KBG doesn't seed anywhere near as much as common KBG, let alone poa annua. Again, if you had common KBG before, or a mix of grasses, the presence of poa annua may not have been readily apparent. Compared with the darker green and uniform texture of all-KBG, it sticks out like a eye sore. You need to get rid of as much as possible now, IMHO. Any seed it produces is a future problem. Either hand pulling or spot-spraying roundup. Your lawn is too young to use Prograss. As you've mentioned before, it's not too late to put down pre-emergent.

If you have poa densely packed in certain areas, I would lean toward a pre-existing infestation. That is it's trademark--extremely high seed production and viability. In the spring and fall, it can out-compete just about anything. If untreated, things can get worse year-to-year but again, may not be noticeable mixed in a lawn of sub-par grass types.

but isnt this "elite" kbg supposed to crowd out the weeds and the poa since it has been said on the elite kbg being so "aggressive", yet sounds like a simple weed can instead crowd out the kbg, which in two or so weeks, it seemed to have done a major portion of my renovation. it sounds like to me that if its present to begin with, then the game is over. by the way, thank you eriocaulon, for i appreciate your thoughts and time youve taken to write. sorry how frustrated i am, just imagine what its like watching this stuff come in for two months, and its the wrong stuff that supposedly is futile.

You're always going to have weeds germinate along with the grass you want. You can reduce the number of weeds by killing the lawn, watering daily for a week to get weeds to germinate and kill again, but it's too late for that.

Everybody keeps telling you that the seeds were already in your lawn, and you keep insisting they were in the seeds from Pawnee Butte. If they sold sod quality seed with lots of weeds, they'd be in all kinds of trouble and would very quickly lose their customers.

The KBG will outcompete the weeds in time, but you'll probably want to kill the weeds in the spring and maybe reseed with some of the spare seed you set aside for that purpose. If you didn't set any aside, keep killing the poa annua this fall and all next year and order some KBG seed for another fall planting. If you keep after it, you'll be getting the seeds that germinate and you should be able to eradicate it by fall.

There are weed seeds of all kinds everywhere and when you water your new grass seed, you provide conditions that are perfect for the weeds to germinate.

Reed through the posts by other renovators. They all talk about fighting weeds for the first year or so.

Then take a look at pictures of their lawns from a year or two later and you'll probably feel it's worth it.

I can understand your frustration. Elite KBG, once established, does form a dense canopy that can minimize weeds. However, it takes forever to germinate and establish and during this time, is vulnerable to a number of weeds. If the poa annua seeds are pre-existing, they will germinate far quicker and grow far faster then the slow-growing elite KBGs that you may not get any KBG establishing in infested patches. Even when established, poa annua is still able to break through even dense elite lawns--me thinks because it is shade tolerant and produces so many seeds. In spring and fall, elite KBG is no match for it.

Still, like others have said, things may not be so bleak. The KBG always looks thin when establishing but hopefully in another month, it will look fuller--should look pretty good since you seeded early and already cut once. Make sure the grass is well fertilized and mow frequently and regularly to promote thickening. I would pull out any poa annua you see now. Pull out any with seedheads first. Be diligent and pull out at least 10-20 per day and you will be surprised by the progress. Don't worry about the barren patches. Hopefully your kbg will spread into them quickly. Again, apply a pre-emergent now--if pre-existing, the seeds will continue to germinate until freeze. apply pre-m in the spring early--way before time for crabgrass. I would continue coverage throughout next year as your lawn may not be thick enough to prevent summer annuals from germinating. Continue to pluck/kill any poa you see and prevent seed from dropping. Your kbg will fill small voids and you can patch larger areas.

Like I said before, it is always helpful to make your own patching sod in box planters--I have been doing this every year in the spring (because of the slow kbg germination) and this is the first year I did not need to use it. Use clean potting media and you should not get any poa--if you do, well then you know the source. Large affected areas can also be reseeded with clean soil and cutting out a couple inches of infested top soil.

bpgreen, the weeds i do not mind because they can be selectively herbicided, its the poa annua only that i care about. and another person called meleca on this lawn care forum also bought from pawnee butte and had crazy poa problem also. if you saw my new lawn and the infestation up close, you'd think that the mix was 50 moonlight 50 poa. a small patch here or there i can understand, but i would bet you would think the exact same thing, especially knowing that the new renovation covered what was a garden.

"Reed through the posts by other renovators."

Arrgh. I meant "Read" not "Reed."

"bpgreen, the weeds i do not mind because they can be selectively herbicided, its the poa annua only that i care about."

I consider poa annua a weed in a lawn setting.

How many times did you kill your lawn prior to planting? Did you kill it, then water it again to get the weeds (including poa annua, which is a weed) to germinate, then kill it again?

If not, what you're seeing is the germination of seeds that were already in the soil. It's that simple. It doesn't matter where you bought the seeds. It doesn't matter that somebody else who bought seeds from the same supplier had the same results, at least not if that person also only killed the existing lawn and didn't get the existing seeds to germinate.

Sod quality seeds don't have weed seeds. That's what makes them sod quality.

I bought seeds from Pawnee Butte and didn't get sod quality (not available for native seeds). I had a handful of weeds sprout, but not very many.

Keep after the poa annua. Kill it when you see it (gluphosate). Don't let it go to seed. If there's enough KBG to fill in, use a pre emergent and you're done. If not, keep battling the poa annua and reseed the KBG in the bare spots. Somebody posted shots of his lawn where he sprayed glyphosate on patches of poa annua and let the KBG fill in (the pictures may have been posted to a different forum).

The bottom line is that you can't blame Pawnee Butte. The seeds they sent you were fine, but you had lots of germination of existing seeds.

I don't think I'm going to convince you of this, but it's the truth. You can either accept it or not. You could try suing Pawnee Butte, but it won't take very much work for them to prove that their sod quality seeds are sod quality and weed feed, so you'll lose.

My advice stands. Battle the poa annua and either reseed bare patches or let the poa pratensis fill in.

dice...i've been following this post, bp and erio are giving you good advice:

1. keep "carefully" pulling 10 or 20 poa/day

2. mow often at a 2 1/2 inches,(and bag it for now, with all that poa, the last thing you need is to mulch poa seed back into your soil)

3. go back to normal watering schedule...1-inch just once a week. poa has shallow roots and likes frequent water and moist soil..so don't keep giving it what it wants.

My opinion, and I'm almost certain of this, you had dormant poa seeds in your soil, and the conditions became perfect for them to germinate when you started your renovation. poa can start seeding quickly after germination(as you've noticed) so even if you only had a little poa in your former lawn, you could've had many seeds in your soil.

have patience with that elite KBG, it takes time for it establish and start spreading.

good luck.

thanks for words everyone...

bpgreen, what about this... i think it was the seeds for this reason.. i left a 15 x 15 plot just adjacent to the new lawn to have a future garden. it was also prepared in the same fashion as the new lawn, but i did not throw down the seeds nor the fertilizer. In two months, the only thing that has grown on it were some purslane and one single goosegrass and some clover, but as far as Poa, nothing...absolutely nothing. And this garden plot, half of it at least, got the daily water. So how on Earth can it not be the seeds? Do you understand that nearly half the new grass on this lawn is Poa ? If it was a few here or there, then I would agree. Please explain this, and thank you in advance.

If what you said about the 15x15 plot is true, you may be right. Do you have any left over seeds? If so, buy a new bag of topsoil(don't use soil from your yard), plant some pawnee seeds in the topsoil and put it in a container to grow...place the container in a very sunny windowsill in your house and keep moist...you'll find out soon enough if the seeds have poa because they germinate quickly.

if you don't have any seed left over, try taking some soil from your 15x15 foot area and do the same thing...except add some fertilizer....see what happens....maybe do both.

diclemeg, people have given you all the advice they can give, and it looks to be very good advice at that. It's unfortunate that things didn't turn out the way they should have for you.

Do you have any seed left? If so, why don't you get some sterile soil and plant some of the seeds and see what grows. If there were so many poa annua in the with the KBG seeds, as you're claiming, there should be plenty that sprout in this test bed. I think you'd be surprised at what lays dormant in your soil.

Look at the bright side. You can cultivate the poa over the next year then zap it with roundup twice and reseed again next fall. Nothing better than watching new seedlings sprout.

nobody is talking about suing pawnee butte. i think youre probably right, it must have been old seeds lying dormant that germinated first week of september. it just seems ridiculous that universal standard practice does not uniformly include both round=up AND a pre=M, of which i only did the former. by the way, i got a weed hound and tried pulling these... i think theres no point, for its too many and too mixed in, it seems all im doing is tearing it up and allowing more poa to grow in. if poa is an annual, when is it gonna die off until next germination????

unfortunately, poa annua is a winter annual--it dies off in the heat of summer. Next spring, it will start seeding like crazy--early and often.

Can you please tell me which pre-emergent is effective in stopping poa annua, while letting KBG germinate? I may be wrong, but I don't think there is one. Tupersan will prevent crabgrass and let KBG germinate, but it will also let poa annua germinate. That's the only pre emergent I know of that is used while seeding.

Many people use the term poa when referring to a single species of poa--poa annua. But poa is a genus, not a species. It includes many other grasses, such as poa trivialis and poa pratensis. These grasses are all much more closely related to each other than they are to something like crabgrass. As a result, almost anything that will affect one species of poa will affect other species of poa.

Poa trivialis is also known as rough bluegrass. Poa pratensis is another term for Kentucky bluegrass.

I think the reason nobody tells you to use a pre-emergent to control poa annua when you seed KBG is that it will stop the KBG from germinating also.

I know I've already said it, but I'll try again.

What some people do to prevent results like you had is to spray the lawn with glyphosate once to kill it. Then water it daily to get the existing weeds to germinate and kill it again. Some people will even do it three times.

Since it's too late for you to do that, you'll have to deal with the poa annua that you have. Kill it and keep after it. The KBG will fill in the bare spots via rhizomes. Over time, the KBG will take over the lawn. If you have seed left over, you can speed up the process by dropping seed in the bare spots.

diclemeg, bpgreen is right about this fact, YOU DO NOT PUT A PRE-EMERG DOWN BEFORE OVERSEEDING KBG, unless of course you want to have poor germination from your expensive KBG seeds...forget what you've read elsewhere, it is simply not something that should be done....end of story.

Second, you absolutely should fertilize when overseeding...i'm not sure why the fertilizer you used killed some of your new grass, (unless you grossly overapplied) but I'm starting to think you used a fertilizer with weed control based on your repeated comments lamenting the fact that you didn't use a a pre-
emergent.

anyway..you have a problem, you can either get to work now and start pulling or spot killing 50-100 of those suckers everyweek until you don't see anymore, OR, you can ignore it and it will get worse next spring....understand, you have a lawn that has soil that is chock full of poa seeds, poa has an extremely vigorous seeding capability....especially in an environment like the one you just created for it..open bare areas with no competition from other grasses and lots of water/ fertilizer....this is a critical time for your lawn, you need to continue to stay on top of this until next June when your KBG begins to really spread and starts to choke out the POA.

my advice, again, just start pulling/killing it on a consistent basis, if you just spend 5 minutes a day yank'n it, eventually it'll be gone. ;)

did i just write that..

diclemeg,

just keep pulling, just keep pulling...I know it looks bleak, it is depressing to see after so much work and $$$.

You have to remember though, that you do have a good stand of elite KBG there. Just keep pulling the bad stuff out and the KBG will fill in the bare spots once it starts maturing.

You've got a long fight ahead of you, but it can be won.

One thing mentioned here is something I've got to get done, grow KBG in some pots so I can fill in the larger bare areas left behind from pulling out my poa problem. I just keep pulling spots out everytime I walk in the grass, a little here, a little there.

I just noticed that you want me to take a close up of my poa, I'll try to get that tonight.

golfnbrian or anyone else.... i got one of these weed hounds... it tends to pull out a 5 inch diameter plug of dirt when i pull a poa weed... is there a better way to pull them out ? maybe im better off just killing it with cotton glove soaked in glyphosate and brush just the poa. and should i be throwing down corn gluten now to stop the poa germination? and do i put down starter fertilizer to get the kbg to further grow ? thanks again.

The weedhound right now is probably not gentle enough for your purposes. The good thing is that poa is shallow rooted and with the soil moist, is easy to pull up. The bad thing is, any part you leave behind and regenerate and continue to grow. The cotton glove-glyphosate techniques works really well. I personally find the stark color contrast between dead poa and lawn to be objectionable.

BTW, ethofumesate (Prograss, Nortron, Poa Constrictor) should not be used on a newly seeded KBG lawn. You might try it next fall though. It is only recommended for fall use for KBG.

if these are young newly germinated poa plants they should be easy to pull by hand...I think you said that you only have 1200 sq feet, so it won't take that long to pull the poa out.

when i moved into my existing home, my lawn was very neglected by the previous home owner and had crabgrass all over the place(among other issues)..i'd go out there for just 5-10 minutes 2 -3 times a week and finally one day i went out there and started wandering around the yard and noticed that it was all gone, you'd be surprised how much you can accomplish if you just do a little every day.

You've fertilized twice in the last 60 days, I think that's plenty for now in my opinion.

should i throw down corn gluten right now to stop the germination ?

You are best with a chemical preemergent. CGM is not very effective according to the reports I have seen.

I'd be wary about using a pre emergent this soon after seeding. The new grass isn't well established and could be vulnerable. Check the label before using it to see what it says about how soon it can be used after seeding.

no pre-emergents, chemical or natural....corn gluten will inhibit root growth on seeds that have recently germinated...you have kbg seeds that have recently germinated.

1. mow at 3" and bag(start a compost for that garden)
2. water
3. pull out poa
4. REPEAT STEPS 1 -3.

somewhat good news is that i have some Poa Constrictor (etmethsufate) on the way in the mail. and ive yanked maybe 50 poa heads so far. looking closely, the kbg stand looks rather unhealthy. i cut it at 2 1/4 but a few mentioned to go to 3 so i will do that.

its been mentioned to fertilize all fall long. this is where i may have gotten into trouble by using wrong fertilizer and not watering it in. WHICH fertilizer should I be using, and WHEN ? are we talking starter fertilizer? or 10-10-10 ? and/or the kind with weed control ? thanks again.

If you have a soil test, that may help guide you on what fertilizer to use. Otherwise, a balanced fertilizer is fine. Do not use any fertilizer with weed control.

In any case, good luck with the poa constrictor. According to the label, it is safe to use 8 weeks after KBG emergence, BUT you ideally want to hit the poa annua at a young stage--they recommend before "4 leaf stage".

eriacaulon and anyone else with knowledge,
thanks... one question.. i spoke to pawnee butte seed company and told them the problem and they spoke to their turf expert, who said to immediately throw down a pre-M like halts right now and then again in the spring, to stop further poa germination. do you agree ?

According to the Halts label:
 DONÂT use on newly seeded grass lawns until after the fourth
mowing. On newly sprigged areas, wait 5 months
before application.

If Sep 17 was day 50, you may well have mowed it 4 times by now. If so, you should be safe to use something like Halts. Halts will stop new grass from germinating, so you won't be able to seed in the spring, but pre emergents will not affect spreading that happens via rhizomes (due to the way the pre emergents work and the way the rhizomes work), so the KBG will fill in the bare spots. If you're diligent about it, the KBG should be filled in really well by next fall. Then if you just keep the new grass tall and water infrequently and deeply, the poa annua won't have a chance.

bpgreen,
when does poa annua stop germinating ? if its done then i prob shouldn't. and if im soon to put the poa constrictor (ethofumesate) down, then doesnt that do the same thing as a pre-M also ? i prob should not do both.

I've always dealt with the weedy grasses by mowing high and watering infrequently. It's so dry here, that if I don't water, nothing germinates. As a result, I really don't have much direct experience with battling the weeds. I would expect that it would germinate as long as the soil temperatures are above 40F. The soil temperatures will stay warmer than the air for a while, so it's probably still germinating.

What's the poa constrictor? Is it a post emergent? Does it have anything on the label about using it with pre emergents or anything about seeding?

Diclemeg...you are outthinking yourself here...

POA constrictor on KBG...according to the label:

1. delay application of poa constric until AT LEAST 8 weeks after EMERGENCE. (NOTE emergence, which means 2-3 weeks after you seeded...and note the words "at least 8 weeks"..which really means 10-12 weeks.

2. For KBG overseeding....fall applications of poa constrictor may result in diminished sod quality the following spring.

so basically this means don't put poa contrictor down on overseeded kbg areas until 3 months after you seeded, and if you do it in the fall, it will result in diminished sod quality in the spring...that would be just great wouldn't it!!!

you might be able to get away w/ the halts, though I personally wouldn't do it on plants that are this young.

Diclemeg...you are outthinking yourself here...

POA constrictor on KBG...according to the label:

1. delay application of poa constric until AT LEAST 8 weeks after EMERGENCE. (NOTE emergence, which means 2-3 weeks after you seeded...and note the words "at least 8 weeks"..which really means 10-12 weeks.

2. For KBG overseeding....fall applications of poa constrictor may result in diminished sod quality the following spring.

so basically this means don't put poa contrictor down on overseeded kbg areas until 3 months after you seeded, and if you do it in the fall, it will result in diminished sod quality in the spring...that would be just great wouldn't it!!!

you might be able to get away w/ the halts, though I personally wouldn't do it on plants that are this young.

Using either etho or pre-m is iffy right now. I still maintain that pre-m sometime in October is worth it. I have seen new poa annua seedlings germinate in the middle of winter when their is a break in freezing temp--I have seen KBG do the same for that matter. I would even do the poa constrictor, making sure to spray as selectively as possible. This may mean buying a better spray gun for your sprayer--I replaced most of my sprayers with a universal one from Tractor Supply that you can buy standardized tips for--the spray pattern is much more uniform. I think if you get the required 2 applications of etho in, you might get good winter kill.

An update...all the poa annua i've been pulling with the weed hound... i thought i got maybe 500 or so, as if I aerated the lawn... and I also put down corn gluten meal...and now, two weeks later, poa seems to be popping up everywhere, moreso than before. this is crazy. I think i know what happened... i put down bales of HAY and not straw, as a cover, when I began....i went to the nursery and thats what they had, and did not know the difference. ive been hearing that hay is full of weed seeds which i assume is also poa??? and now i feel like i should put down Pre-M now because the corn gluten doesnt seem to be working. There are lots of seedheads forming, too. And this week I also had a soil test and the soil was slightly acidic at 5.8 and applied the necessary lime. Yeah, I know, I should have done this when I started. Maybe this can be a guide of what not to do. Any further suggestions would be greatly appreciated.

I would not think hay would have poa annua but who knows. In any case, even perennial rye seeds is a weed for you. If there is annual rye, it should dye out. I think next year some hard decisions need to be made. I know you put in a lot of work already, but sometimes it is better to start over (as has been suggested) than to fight the problematic start that you've had. In the end, an all-elite KBG lawn will be worth all the trouble I think. For me it has been an endless source of joy--both to maintain and appreciate.

eriocaulon,
thanks. but the thing i really do not understand, regarding the possibility of starting over... what would prevent the same problem from occuring? (i only planted approx aug.1) 14 days ahead of recommended time, and the standard procedure supposedly doesn't kill the "millions" of poa seeds that everyone tells me about. so how would starting over guarantee anything other than the same result ? this is why ive been so miffed about the common procedure which says to essentially plant at the exact same time as when poa rapidly germinates, yet this procedure makes no mention of preventing the poa from doing so, and thus, anyone who has lots of them in their soil will be essentially screwed. i was mocked by a few people in here saying im blaming others. i am not. i just do not understand how the 600lb elephant in room when starting a new lawn, the huge pitfall of poa germination in fall is never mentioned nor planned for, in the typical 'establish new lawn' procedures.... anything that has been proposed so far still does not account for those who have these supposed millions of poa seeds lying dormant 'for even decades' in their lawn. i presume if i were to start over, it would include a total kill of everything, not just round up. i think the stuff is called zapam ?? anyway, if i were to do a do-over, what would be the procedure so i completely avoid any chance of this poa problem?

As BPGreen mentioned earlier, you can make several roundup treatments (with watering and fertilizing in between treatments to promote weed seed germination)--which most people do NOT do. That will do a lot to reduce your weed seed liability.

You also mentioned use of a soil sterilant. They are not 100% effective but can significantly reduce the viable seed counts. You are probably thinking of Basamid (Dazomet), which has been extensively studied and shown to be effective.

If your lawn is salvageable, I would recommend pre-emergent coverage starting early spring until summer, and then resuming coverage late summer, with Poa Constrictor use in the fall. If not, I would roundup any visible poa patches and use lawn coloring so the dead areas are not conspicuous--focusing in on preventing seed deposition.

By next spring, I think you will have a better idea of how your renovation turned out. Frustration and disappoint is understandable but do not let it get the best of you.

If the weed you've got is poa annua, it's an annual weed, and it sprouts when there's bare dirt for it. If you treat the KBG right, it'll fill in when the poa annua is dead and choke out the poa annua. You can hurry the process along by killing any poa that does pop up and seeding more KBG.

As you noted, if you've got lots of poa annua seeds in the soil and you start over, you'll germinate those all over again. Since you've shown us pictures of seedheads, the weedy grass has gone to seed, so you've definitely got seeds. The only way to make sure you get most of the weeds out of there is to kill, water to get remaining seeds to germinate and kill again. Even this won't necessarily get rid of everything, since you probably won't get 100% germination (weeds and native grasses have especially high rates of dormant seeds that will sit through at least one cycle and germinate later). And you can get seeds to blow in from nearby lawns as well.

But the bottom line is that you just need to care for your lawn properly going forward and the KBG will take over. Now that you've seeded your KBG, you can put down pre emergents at the proper time to keep the poa annua from germinating. That won't stop the KBG from spreading, since that happens through rhizomes, not seeds. If you water deeply and infrequently, mow the lawn at the highest setting on your mower and give the lawn 3-4 lbs of actual N per 1000 sq ft per year (in 1 lb doses), the KBG will flourish and will crown out the poa annua.

Diclemeg, you've made some mistakes, but your lawn will recover from these mistakes because you planted KBG, which WILL eventually spread and crowd out.

one negative about moonligh though is that it's one of the weaker spreading elite kbg's.

read bpgreens final paragraph and follow those instructions...also, I would normally agree 100% with bpgreen on mowing height, but in this case, I'm going to suggest mowing at 1.5 - 2 inches(starting next spring) because of the 70% Moonlight.

MOONLIGHT (quick bio from summit seed website)
Darker green, very dwarf growth, drought tolerant, performs well under moderate maint, med. texture, compact type

i'm familiar with compact dwarf KBG's and they just don't grow that high, and they tend to be slow growing. considering that this is "very" compact type, I'm going to suggest that you mow it at a lower setting to promote as much rhizome and tiller activity as possible....there certainly is a trade off here, mowing KBG high is usually helpfull as a general rule of thumb, but i don't believe so with this cultivar in this situation.(though I would mow it higher(2.5") as summer heat approaches)

diclemeg

Your are an idiot. Do you even read the well thought out contributions regarding your problems? The posters have shown so much patience. IF YOU DO NOT KNOW "how to aviod getting the same results" while starting over read slower - USE ROUNDUP. WATER FOR 1 WEEK. USE ROUND UP AGAIN. THEN SEED.

actually useurhead, youre the idiot, unless of course, you can tell me exactly WHEN the time i should plant, to perfectly catch within the "1 WEEK", the poa annua germination, because, as you already know, that glysophate won't kill seeds will it, so if the poa just doesn't happen to germinate in that "1 WEEK" between Round-ups, I won't be killed, will it, idiot... leaving me with the same problem as before. I'm very thankful for the posts by others, and have said so a few times.

Poa germinates when soil temperatures are between 50 and 70 degrees.

Since we renovate in early fall, when soil temps are still above 70 degrees, fumigation is then a necessity to sterilize the poa seed.

diclemeg,

In the past I have treated moderate areas of POA that kept coming back. 20-50 sq/ft areas, and some smaller. These areas are a bit shady and damp, very good POA enviroment.

I hit the POA with round up.
Waited for the death.
Then heavily aerated the spots, or vigorously raked them to loosen the first inch or 2 of soil.
Seeded with elite KBG, raked in seeds.

Well, in weeks these areas were mostly KBG. But by next spring there were more POA spots in different places.
I was able to grow mostly KBG in the areas that I killed off the POA. The following year, more POA showed up, but not because of my actions, but the more due to the shady damp area of my front lawn I was trying to grow KBG.
I gave up treating this area until I get rid of the trees that shade it.

What's my point? I can't imagine your entire lawn shady and damp like my front corner where I keep getting loads of POA no matter what. You may have just been unlucky in your first attempt at seeding...or maybe it was the heavy dosage of the wrong fertilizer that stunted your KBG growth that allowed the POA to dominate.

What can you do? Get some RU now, and carefully spray the POA. Hopefully it will kill it, it is pretty late to try, but worth a shot. Next...wait. Wait until the ground is frozen solid. Then spread some KBG seed on the bare spots, dormant seed. Then wait, do nothing. Enjoy the winter and forget about the grass. Wait until at least the middle of May before doing anything. Hopefully the seeds will have sprouted. Oh, there will be some POA, but there will be some KBG there too. This will improve your situation, it won't fix it, but it will help and really is all you can do now at this time of the year. It is better than waiting for next spring to take action.