[KerbDMK]

It seems whatever I do, I can't get rid of dead grass blades in my lawn and they never seem to decompose. Dethatching only seems to get rid of about half the dead blades - going over it twice.

Here's a before and after dethatching.

Before
View attachment 514824

After
View attachment 514826

The lawn looks OK from a distance, but up close you see lots of dead blades and thin grass that I want to thicken.

I fertilize on a regular basis and these photos are during the wet spring we've had. I'm in the northern Idaho climate.

View attachment 514830

Most of the lawns in my area look like that this time of year. Seed heads and stems are dying now, soil temperatures are climbing, and fine fescues are going dormant (I think I see that in your lawn). In addition, the spring flush is over, and the grass is shedding un-needed leaves and its deeper root structure because of the high soil temperatures.

 

[KerbDMK]

How old is your lawn. If it's 30 years or older you may want to consider starting over with modern turfgrass varieties..

 

[KerbDMK]

The house is about 19 years old and the lawn was put in then. I've overseeded each fall for the past 3 years.

I've used multiple mowers and still the same issue, and if I would have zoomed in on the mowing video, you'd see dead blades that are still attached to roots. I just wanted to show what mowing low pulls out.

The original lawn may have contained a lot of fine fescues, and 19 years is long enough for it to overpopulate and become a nuisance. You may want to renovate a small area of your lawn with an excellent new variety of grass this fall and see how that compares to the rest of your lawn next summer. If the new grass solves the problem, you can do the rest of the lawn next fall.

 

[KerbDMK]

I would start with one or more of your local universities, they will have information on the varieties that perform well in your area and how to do the renovation.