Thanks for reaching out. 

Annual bluegrass (Poa annua) is a tricky weed to manage. The techniques that work on it will also affect your desired lawn grasses. Here is a quote from one of OSU's turfgrass experts,

"Annual bluegrass (Poa annua) is one of the two grasses that dominates lawns in western Oregon and Washington. The other is bentgrass. The only way a homeowner can kill annual bluegrass is by selectively spraying out the patches with glyphosate (e.g. Roundup), and then reseeding. Be careful as glyphosate will kill any plant it touches.

To give you an idea how difficult it is to control annual bluegrass, all golf courses in western Oregon and Washington older than 25 years have converted to nearly 100% annual bluegrass in spite of having spent many millions of dollars on maintenance budgets and trying to control it. They have all failed. My recommendation is to embrace it. In a few years, the patches will coalesce and you won’t have the mosaic effect. You can still have a very nice lawn. Go look at a local golf course and see how nice it looks. The key is good maintenance: consistent mowing, fertilization, and irrigation. Annual bluegrass does not like drought, so it is important to irrigate it frequently in the summer." – Brian McDonald, OSU Extension turf specialist

So unfortuantely, there isn't an easy fix to managing this problem withough going through renovation process. Let me know what additional questions you have. 

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Thanks for reaching out. I checked in with OSU's turfgrass specialist, Chas Schmid, on your questions. Here are his responses:

Question #1: As I mentioned earlier, front lawn is about 9,000 sf. Can I discourage Poa some by over seeding more than 1 year with my prerennial rye . And try to get a very dense rye lawn ?A: Unless there is a void/bare spot in the lawn, I don't see a benefit from routine overseeding of your lawn. At this point, you are better of starting from scratch and reseeding your entire lawn (or the most important areas). If you are interested in this option, I am happy to have a conversation about species selection and how to get a clean establishment.

Question #2: Am I wasting my time and $ by overseeding with the rye ?A: You will probably get some ryegrass to germinate and establish, but I don't think you'll notice a shift in the ryegrass/Poa population.

Question #3; If I let the Poa take over do I need to mow lower than I would now with the rye. Now Im mowing at 2 1/2- 3 in.? Reason I ask is because of the seed pods or sprouts that you see when Poa gets tall. I don't like seeing that .A: Yes, you can mow your lawn a little shorter to try to clean up some Poa seed heads, but it can produce seed heads when the grass is mowed at <1/8" so you will definitely still see some. You could mow the Poa and ryegrass and 2". Just remember the shorter you mow the grass the shorter the roots, so it will require more frequent watering (and more total water).

If you have further questions you can reach him directly at <personal data hidden> Take care!