my yard in 2008, seeding helpful?

[bunkers]

This was my yard in May, 2008 --- not great, but looking decent to me and we had a couple late snows in May, so I really can't start cutting it till later May.

http://i188.photobucket.com/albums/z320/taybrynn/P1040228-1.jpg

http://i188.photobucket.com/albums/z320/taybrynn/P1040229-1.jpg

http://i188.photobucket.com/albums/z320/taybrynn/P1040230-1.jpg

http://i188.photobucket.com/albums/z320/taybrynn/P1040231-1.jpg

Well, to make the story simpl, things got really bad by the end of June ... and it seemed like it was all dead thatch everywhere. So I dethatched with a pull behind dethacherator (in the bad spots only) in midsummer which was probably bad, but removed about 50 bags of dead grass.

I later applied an insecticide as well, to entire lawn ... the stuff with Sevin in it.

So it did look somewhat decent right around the sprinkler heads (using hunter PGP rotors) ... but terrible most other places.

The wasn't just browned, it was hard (like walking on cut straw) and dead. It was not dead in circles or anything that would indicated mold. My yard does sit under snowcover for 1-2 months each winter, usually from mid December thru mid Feb. I am at 6500' elevation, low humidity and very low water this year ... 3.5" from Jan -> Jul.

Recently, things are much better, humidity is up (never bad in CO) and temps are down under 90's. THe yard is making a miraculous recovery.
I am wondering if it will fill in on its own, or if I should hand aerate spots and just overseed the deads patches that are remaining. Here are pics from the my just today:

ok, first the good parts:
http://i188.photobucket.com/albums/z320/taybrynn/P1050942.jpg

http://i188.photobucket.com/albums/z320/taybrynn/P1050943.jpg

now, these are the parts that are still recovering ... and I have hand cord aerated them, but am considering some spot overseeding, or possible seeding into aeration holes and then composting mushroom compost over the top slightly.

http://i188.photobucket.com/albums/z320/taybrynn/P1050944.jpg

http://i188.photobucket.com/albums/z320/taybrynn/P1050945.jpg

[mngrassguy]

How much and when do you water? How tall do you mow and how often? How much and when do you fertilizer?

What is a "hand aerator"? Rent a machine and go in both directions.

As far as seeding, do the whole lawn unless you are using the exact same seed as the rest of the lawn. You wouldn't want "patches" of different kinds of grass growing in the yard.

Never dethatch a lawn in the summer but it sounds like you already knew that. Why did you do it? Most likely the grass was just dormant, not dead.

I've been to Castle Rock. Nice country. Needs some trees.