It's not Poa. Poa grows in the spring, and generally dies and disappears in mid July. (That having been said, I have read articles, in golf professional magazines, that say that there are some 'perennial' species of poa, rather than the common poa, which is an annual. If you've run across one of those, well, good luck with it.)

Poa is odd because it's an annual. It sprouts, and is aggressive, in the spring. It does not, however, germinate in the spring: it germinates in the fall. That's right, germinates in the fall, which means that you have a few thousand poa seeds, in your lawn, that have just germinated (September and October), and they will sit there, as live seeds, and they will grow in the spring. There's nothing you can do about it, and the pre-emergent you put down in the spring will have no effect on it, because it germinated back in the fall. Pre-emergents stop seeds from germinating, like weed seeds.

So the poa will grow. And it will dump a million seeds on the soil. And your pre-emergent will expire, in August (pre-M's last about four months) and the poa seeds will germinate, again, in the months of Sept and October.

It's a never ending cycle, unless you determine that you're not going to be putting down any real grass seed, and you can put down pre-M both in the fall (early Sept) and in the spring, and hope to interrupt that cycle. But obviously, re-seeding, when you're putting down a pre-M, is out.

thanks. So how did I get KBG in my lawn? From the scott's seed?

You can identify which turf it is, by using this link.

Here is a link that might be useful: Turf Identification

Give it a month. The seeds are just germinating. Then the seed heads show up a couple of months down the road.

used the id tool and I get 85% probability of KBG, 45% for Poa. Of course it does not take into account when the growth is occuring (spring vs. fall).

quirky, are you referring to the KBG that is present or the POA? Does POA grow in the fall/winter?

When you say poa, are you referring to poa annua (annual bluegrass)? Poa actually encompasses quite a few grasses, including poa pratensis (KBG) and poa trivialis (roughstalk bluegrass).

If the grass looks "almost" like KBG, it may be poa trivialis.

Frequently, poa trivialis accounts for a fairly good amount of the seeds listed in "other crop" or "weed" seeds on the label. That's why many people insist on sod quality seed (unlikely to be available at your local big box store).

Unfortunately, poa trivialis can be very difficult to eradicate.

I was referring to annual bluegrass. So the Scotts Premium brand is not considered 'sod quality' and could have these weed seeds?

The seed bag should have had some numbers for crop (or other crop) and weed. Those should be 0% or very close to it (but by very close I don't mean something like 1%, I mean something like .01%). You'll get 0 or nearly 0 with sod quality seed, but not typically seed you buy at the store, so the weeds you're seeing could have been in the seed you bought.

I mean the poa annua. Down here in GA it grows like mad through the winter. If you have a severe infestation you will be mowing it all winter long. Where Philes is, it may not do much until spring. Usually by now you have a lot of poa sprouting up. You may not know if it is poa until later when the seeds form or if the color doesn't darken up. It can look like KBG but much lighter (P. annua)

so I did a little more investigation and...

I really inspected the blades and DID find a very small 'scotch tape' thing !

I've attached links to a few pics of what I am seeing.

To be fair, I honestly don't remember if the same thing happened at the same time last year. I DO know, that there were not dead spots during the summer months, so if this is poa then it would be the first year. I wasn't really into the lawn last year so I don't remember if this current growth I am seeing can up last fall as well. The areas I am showing was an existing lawn, so quite possible it contains some KBG. The back lawn was from sod, but again I don't remember what happened last year so it could also be coming from the sod.

As you may or may not see in the picture, the spots are not really 'clumps', except for the last picture. The others are sort of intermingled with the fescue; and from what I can tell the color is only slightly lighter than the fescue; I do remember the stands coming in lighter, then getting progressively lighter as they establish. The one this I notice is that they are very easy to pull from the ground, and their root system is not like fescue.

Pic 1 is of the 'grass' is in the lower center, near the concrete.

Pic 2 it is more intermingled, but you can see, slightly right of center, that the grass is different.

Pic 3 you can clearly see clumping. This one looks different then the other areas.

If what I have is POA, it is everywhere. Uniformly in the front and intermingled, getting uniform in the back. Again, I have nothing to compare this to from last year, but if this all came from the Scott's product then A) I got a bag full of nothing but weeds, and B) if this is POA, I'm going to have a bare lot come summer.

Any help would be appreciated. Thanks !!

Here is a link that might be useful: photos

To my eye (a tighter closeup would help a lot) that looks like Poa trivialis. I've seen triv sprout in spring, but fall seems to be its prime time. It likes damp conditions and shadier areas, tends to be a midrange, intense green with a lemon-lime overtone, and grows fast.

Eh, well, good luck with that. There are three ways to get rid of it:

1) Dig it out. Don't miss any roots or stolons or you'll get it back.

2) RoundUp.

3) Certainty herbicide, which is very expensive but works well on P. trivialis. Certainty doesn't spare tall fescue, so that's not an option for you.

Interesting. when I use the turf ID tool for Rough Bluegrass it states that the leaf surface should be ridged. The leaves I am seeing are smooth. Also, the tips are not exactly 'boat shaped', that is, they don't look like they have been 'pinched' to a point. They just sort of come to a 'rounded' point. Maybe I'm not seeing it because the blades are not large enough.

Also, it does not seem to 'stand out' color-wise. In some areas I cannot tell the difference between the fescue with respect to color; I have to get down and take a closer look and examine the blades.

If it is an objectionable weed/grass, not much I can do about it now. It has come up everywhere. But when it comes up, it is not 'lime green'. It actually looks pretty good !! So I guess I'll just wait and see?

Please keep the info coming..I'm learning a lot !!

I think it is Poa Annua. It spreads more from seed than Poa Triv. I have both, though I blasted a ton of triv this August with Round Up. I have been pulling my POA Annua. The roots are real fibrous and come out easily.

gryd, I did notice, as you pointed out, that it does come up easily..much easier then established fescue. Still not sure what to do....but keep the info coming !

When you say 'spreads more from seed' are you talking about seed heads to seed from my Scott's 'Premium' blend fescue mix?

Also of note, I aerated for the first time in probably years..at least since I have lived there. Maybe bringing some seeds to the surface?

added a few more pics. Continued help would be appreciated. Thanks !

Here is a link that might be useful: pics

As far as management goes, which at this point I can really 'see' the color difference and it is growing faster than the fescue, and also I've been seeing some seedheads low to the ground. This make me think that it is poa, and if not, it still does not look real good. As far as fixing the problem, I have two situations:

The backyard has only a few spots and they are small. Thinking of cutting them out, down to the topsoil, and filling in with....new topsoil? mulch? Basically something there to hold the shape until I can re-sod the patches in the spring.

The frontyard, I'm afraid, has the poa more dispersed. A lot of it upon closer inspection. I figure I can just let it be, and if it is poa then it will take over. Either way the front lawn will be redone in the spring. If it is not poa, then I have a nice yard come springtime.

Any thoughts? Anything I am missing? Thanks again all !

Here's a link, which might help.

Here is a link that might be useful: POA Arizona

After seeing the new pics I'm fairly sure it is Poa Ammua. I doubt it was in the Scott's seed but probably was in your soil and exposed after aerating. That's what happened to me.

That's not Poa trivialis, my bet's on the annua.

Dig it out, Round it Up, or, alternately, import some of the brush fires from south of you. :-)

Ten to one it came up from the soil with your aeration, and you'll just have to work on it over time.

Well we just had an earthquake here to maybe it will just shake itself loose...:)

I think maybe I have both?

Pic 139-3941_IMG is a bunch type, long roots with little or no stolons. The blades are thinner also. The areas (only one or two) where this shows up are clearly defined, as in a 'bunch' of grass. This is the Poa Annuna?

Pic 139-3940_IMG is what I see in most of the affected areas. Runner-type, lots of stolons, thicker blades and not bunchy. Also the roots are very shallow and easy to remove. This is the triv?

Yeah, thinking about it it was most definately the aeration.

Thanks all. I'll get right to pulling it up.