Hello.
I have moved to a house a year ago that is approx 30 years old, the lawn at the back slopes away from the house at a grade of approx 20 degrees. Large areas are in continual shade.
One such area I tilthed up this spring and spread Shady Grass seed over the area. This grew thick and strong and after a couple of cuts was doing well. Part way through the summer it started thinning out and now I have an area of thin strandy grass that doesn't appear to be growing back hard as I would expect it to.
The rest of the lawn looks pretty good on the surface, but is suffering from moss infestation underneath which I have been raking out and spreading new grass seed over. Today after closer inspection I find that great swathes of the grass come up and the grass has a very shallow root and no strength to it. I pulled a good couple of square feet up very easily to leave nothing but bare soil behind.
I have started to areate the soil in places where it may be compact and preventing good grass growth, but I would have thought the darn stuff would be growing back quicker than it is.
I am wondering if it could be leatherjackets nibbling the root system away or just the moss growing underneath the thatch of the lawn.

Any thoughs/comment would be grately appreciated!

I am happy to post links to pictures if this would be helpful.

thanks.