First you want to be sure the pre-m you apply is effective in preventing Poa seed germination. Not all are. Then, you want to be sure you apply it timely in spring (March/April) and fall (late August/September). Poa doesn't germinate in winter, so no need for the December application unless it is a product that will last through spring.

Fescue doesn't pop up or suddenly appear like weeds do. You may want to show us some pictures of those. Here is how to post pics and how to resize them if they're really large.

It's possible it just went dormant (turned brown) for lack of water and will return when temps are more favorable and moisture is available. Provide 1 inch of water per week.

Please explain/describe why you think you have fungus. Maybe post pics of those areas also and closeups of affected leaf blades. For a positive diagnoses, here is plant pathology information and sampling instructions.

Yep, you can begin now or maybe just wait a few days. However, you can't apply pre-m for Poa if you plant seeds.

Overseeding isn't complicated, but maybe not quite as simple as you stated. In the following outline, every step serves a purpose that contributes to success from getting optimal germination to ensuring survival. For example, the (1st step) soil test serves to check the pH balance of the soil (as well as other nutrient balance and soil structure). It will determine if you need to apply lime or sulfur to raise or lower pH towards neutral. This is beneficial not only for the new grass but also for the existing grass. Another example are the instructions in Step 2 to gradually mow the existing down short. You need it short so the seeds have better chance of getting contact with the soil, providing for better air circulation, and increasing chance the new seedling get sunlight. Otherwise, the existing lawn will shade them, which is going to happen anyway as it continues to grow, so best to mow it down to begin with. Mowing it gradually preserves the rule to never remove more than 1/3 of the grass blade to prevent stress. I'll be happy to provide any further explanation of the steps if you want me to.

1. Get a soil test. Call your nearest Ohio State University Cooperative Extension Service for a test kit and sampling instructions. It will likely take two weeks for results. If you need to apply sulfur, lime, or any other amendment per test recommendation (that is not applied in Step 5), you can do it after seeding if you don't get results back in time.

2. Mow to within one and half inches, but mow it down gradually. Cut off 1/3 the grass blade and another 1/3 three or four days later. Repeat if necessary.

3. Rake it up

4. Core aerate or cheat and apply Nitron A-35 to relieve soil compaction.

5. Fertilize

6. Sow seeds (slit seeding is best)

7. Topdress 1/4 inch layer compost, peat moss, or clean straw (weed-free). (One cu. yard/1000 sqft).

8.
water 15-20 minutes twice a day for two weeks
water 20-30 minutes once a day for one week
water 30-45 minutes once a day every other day for one week
water 30-45 minutes once a day twice a week for one week
move into deep irrigation, increasing the time to provide 1 inch of water all over and decreasing the frequency to just once a week.

Starting off, the schedule supplies roughly 1/4 inch of water, then increases that amount while decreasing frequency of application at the same time. Like practically everything that concerns lawn care, this schedule is a general guideline and should be modified to accomodate your specific conditions. The lengths of time should be modified if you have an automatic sprinkler system since that will not take as long to provide adequate moisture. So, decrease amount of water (time) but maintain frequency as is. The tuna cans test is recommended. If it is still especially warm, you may want to irrigate 3 times a day (10-15 minutes if necessary) for that first couple weeks. Your objective is to keep the upper 1 inch of soil moist and not let the seeds dry out.

9. First mowing is when the new grass reaches two inches. However, the existing grass will be considerably taller. To prevent damage to the old and new grass, you'll have to mow down gradually again to the point of mowing 1/3 off the new grass. You do want to get the new grass mowed early at this time in order to promote tillering. Then, you want to gradually raise the mowing height to desired length of 2.5 inches. Higher if you prefer.

Continue with the same grass seed if you like the grass. Of course, that being the origin of the Poa is very likely and has been a problem for a couple years now, making it even more necessary to be sure you're planting "sod quality" seeds. Sod quality seeds are much more closely inspected for foreign seeds so less likelihood there will be Poa. If you like the grass, perhaps find out the varieties that are in the blend and purchase them individually from elsewhere, someplace where you are able to ask for sod quality seeds specifically. Perhaps I can help with locating them if you tell me what the varieties are.

Boy that's a lot. Hope it helps.

Well, in addition to Bestlawn's excellent overview, one thought comes to mind. If you have put down alot of pre-m, you may not be able to overseed effectively.

When did you last apply what pre-m? I'd check out how long it is supposed to be effective?

Regardless of the heat factor you inquire about, you are probably better off to wait awhile to overseed to let the pre-m lose some effectiveness before overseeding.

Pre-m's do vary quite a bit on how long they claim to be effective for. Check that and when you last applied in deciding when to overseed.

Thanks for the great information! I have attached/posted pictures of my lawn and the trouble spots.

Just in case these pictures do not appear, they are posted here also:

http://www.pbase.com/meleca/lawn_2007

I do have a few follow up questions:

1. What is the best seed (blue grass) to put down in South West ohio (dayton Area)? Should I mix two different types?

2. Where should I buy the seed?

After looking at my lawn pictures will slit seeding do more damage than good? In other words is the machine hard on a established lawn?
Here are pictures of my lawn's problem areas

http://www.pbase.com/meleca/image/84083978.jpg
http://www.pbase.com/meleca/image/84083979.jpg
http://www.pbase.com/meleca/image/84083974.jpg
http://www.pbase.com/meleca/image/84083975.jpg
http://www.pbase.com/meleca/image/84083976.jpg
http://www.pbase.com/meleca/image/84083977.jpg

I am far from an expert, but I do read these boards religiously.

I just overseeded, so I have some insight there. I started by dethatching, as I had a lot of thatch. Then I used the slit seeder. I also did it with my neighbor's lawn. Here is my 2-part response regarding your question about whether it will damage the lawn:
1) If you move very low (as I did with my yard) prior to slit seeding, you will definitely notice that something was on your lawn. I don't think it necessarily looks bad. In fact, I think it looks good. It is the topdressing that people might interpret as looking bad. I have gotten a few "What the heck happened to your lawn?" questions since topdressing with compost and peat moss, even though I only put a light layer down. The good news is that it will all either sink into the soil or be covered by growing grass within a week or so - so it really isn't a problem.

2) With my neighbor's lawn, I didn't mow down low. I was doing him a favor, and I just didn't have the time to go 1/3 down over a period of several days. So I just dethatched, mowed at a medium hight, and then ran the slit seeder. His lawn looks fine, aside from the brown parts that were there anyway.

Bestlawn, thanks for summing it all up. Your post should be stickied for life. :)

Did you by chance check out my lawn pics?

Also What is a good choice for seed blend and a good place to buy it?

thanks again

I'm still looking for a solution to my Annual poa in a few places and this strange weed (see last pic)
Here are pictures of my lawn's problem areas

http://www.pbase.com/meleca/image/84083978.jpg
http://www.pbase.com/meleca/image/84083979.jpg
http://www.pbase.com/meleca/image/84083974.jpg
http://www.pbase.com/meleca/image/84083975.jpg
http://www.pbase.com/meleca/image/84083976.jpg
http://www.pbase.com/meleca/image/84083977.jpg

Also, what is a good choice for seed blend and a good place to buy it?

thanks again

Here is a link that might be useful: lawn pics

can anyone shed some light on my problems......

{{gwi:113649}}
{{gwi:114317}}
{{gwi:113646}}
{{gwi:113648}}
{{gwi:114318}}
{{gwi:113647}}

Thanks for helping me with my pics Parafly......

This one should be posted as well.......its my problem weed:

http://www.pbase.com/meleca/image/84083980

If you want to overseed now, you'll have to skip any Poa control until spring. Since you're seeding anyway, just use the "R" word stuff in advance on the fescue. Have you done the soil test yet?

Midnight
Bedazzled
Prosperity

You can purchase these from
Pawnee Buttes Seed pawneebuttesseed.com
800-782-5947 ask for Glenn
Tell him you want sod quality seeds
You need 2 lbs/1000 sq ft for overseeding

No problem - just do this (delete the space between the first
{{gwi:114319}}

Does anyone know what is embeded in my KBG? See below

I could be wrong, but it looks like fescue to me.

How can I control it so it stays away from my KBG!

DO I just keep pulling it up when I see it?

I think that any chemical that will kill fescue will also kill KBG. If you're using chemicals, you can spot spray. If not, you can pull or dig it as you see it. Digging will probably be more successful since fescue can have deep roots.

Thanks for all the good info!

Just one more question.... Below is a pic of my POA problem.

{{gwi:113646}}

My question is:What will happen if I slit seed over the POA grass? Might it help to rake the stuff on top of the soil out before I make a pass with the slit seeder?

thanks again

rich

I may be wrong...but in that last pic, it doesnt look like POA to me. Looks like a fescue of some sort...Maybe the lawn is a seed blend. That particular part of the yard was stressed from the summer heat and that fescue blend survived in that part of the yard while the others died off from environmental concerns?

Rich, I'm wondering if you need more than I stated in my two posts. I don't see that I missed your questions, so please inform.

I was told by LESCO that this stuff here (below) is POA....It sure is taking over my KBG! In some spots

If its not any Idea what it is? Can someone post a pic of POA? As Far as I know, the sod came from a strickly KBG sod farm in south west ohio. (Gerdies Sod Farm)