Hi Doug, thanks for the question.  

We have had a rather mild winter but after our latest storm we had a lot of snow and a very quick melt.  This suggests a lot of water possibly causing damaging the leaf blades which then matted together.  This matted turf can prevent air from getting to the plant doing more damage.  The moisture can also encourage pathogens.  In the one picture there is a downspout suggesting the area was also getting water from the roof.  Water could be settling in lower areas.  The best thing you can do now is to lightly fluff up the matted grass with a rake (some use a blower) to allow for good air circulation. Factors that can add to matting include thick thatch, compaction and ponding.  Core aeration and leveling can help with these.  Watch for new growth in spring and overseed if necessary. Warm season grasses are said to be more susceptible to matting.

The broader picture seems to show parallel lines of damage possibly due to mower (dull blade), or a drop spreader application.  Something you may ask your lawn service about. 

I hope this helps.

Thanks for your feedback.

 This problem has been occuring the past several years, but has not been that noticeable until the end winter. This winter has been the worst. For some reason the backyard  (pictures previously provided) is worst than the front yard.

I usually keep the grass cut at a height of 4 inches during the spring/summer and get down to a height of 2 1/2 inches by late November for the last cut.  Should the last cut be shorter than 2 1/2 inches?  Could the longer grass be causing the problem?

The lawn has been dethatched the last three years.

I purchased a new blade this past spring and sharpened the blade during the summer.

The backyard is flat with no low spots and the yard has a slight slope away from the house.  Also beneath the topsoil is gravel, which acts like a sponge, so no ponding ever occurs.

The fertilizer service used a riding fertilizer spreader and applied 5 applications this past season which included grub control.  The lawn looked great all year.  Could grubs be causing the damage?

Thanks again for any feedback.

Hi Doug,

Thanks for the additional information.  Turf questions can be difficult to determine without being on site. It is doubtful that cutting the grass shorter than 2.5 inches in the fall will help. Thatch in moderate depths (<1/2 inches) is actually not a bad thing. Dethatching is hard on the turf and should only be done when needed. If your lawn is building up thatch quickly, you may be overfertilizing (excessive nitrogen).  The fertilizer used may not address deficiencies of other nutrients (e.g. potassium). This can make turf more susceptible to winter kill and can cause grass to lay down. A soil test is highly recommended. Grubs should not be a problem if grub control is applied at the appropriate time. Grub damage should show up in the fall.  You indicated a gravel sub soil.  This could create a situation where turf can easily desiccate. You had also mentioned that the back yard seemed to be more vulnerable to the damage.  Does it receive more shade?  Is it windier than the front? is the soil different? What is your soil like (sandy, silty, clayey)?  What type of grass/grasses do you have? 

Check out the following links:

Cool-Season Turf Winterkill: Potential Losses and a Pathway to Recovery | Purdue University Turfgrass Science at Purdue University

Winterkill of Turfgrasses (psu.edu)