On Tue, 29 Aug 2006 15:30:28 GMT, blueman wrote:
I have a relatively small lawn (maybe 5 thousand square feet spread
across a couple of patches) that has developed seemingly more brown
than green spots, including a bit of a mat of dead grass.

I know I need to do something to condition the soil and re-seed this

First, cut some sod samples to see what's going on with the soil, in both a
green and a brown patch. Water first with a sprinkler for 15 minutes before
trying to cut the sample, and then wait 15 minutes before cutting. Can you get
a spade in easily? If so, it probably doesn't need aeration, unless you've
got traffic lanes (a dog patrolling your fencelines, a mailcarrier wearing a
path, etc.). Is there a difference between the two samples in how far the water
penetrated into the soil? Is there a lot of dead stuff (like more than 1/2 inch)
just above the soil in brown areas making a layer that water doesn't penetrate?
If not, you don't have thatch (and chances are, you don't have thatch anyhow --
unless you've been feeding the lawn quite heavily.
http://www.extension.umn.edu/distrib...re/DG1123.html

Were the brown areas quite green in cooler temps, and the areas that weren't so
green are now green? If so, that suggests you've got a mixture of warm season
(Zoysia, buffalo grass, crabgrass, etc.) and cool season (bluegrass, fescues)
in your lawn, and they're reacting quite predictably to summer temps.

If you get back to us with the results of that spade test, we can suggest
some better ways of going on.

Personally, I'd start with a soil test, especially if you've not been liming and
fertilizing regularly. That's no matter what the spade test shows. I'd also
pull a sample for a shake test, to determine particle size composition of the
soil.

My gut feeling is you've probably got a mixture of warm and cool season grasses;
if the warm season grass is crabgrass (it'd be green now in hot weather), it's
an annual and can be "cured" with proper fertilization, mowing and overseeding.
Might want to poke around on the web and match pictures of blooming/seeding
grasses in your lawn to some of the common lawn weeds.

Assuming you've got crabgrass, I'd suggest running through the areas with a
tiller, scattering (by hand)
in good fresh lawn seed of desirable species, firming up the soil, and
then watering this fall. Apply lime and a good "starter fertilizer" without
pesticide this fall; lime and a spring fertilizer next year. And get the mower
blade sharpened... one of the biggest causes of ratty looking lawns.

Kay