I don’t know what is wrong with my grass! The only thing different. I did was put down moss Killer. The back is shaded I have included pictures. It looked great in the spring! I fertilized with lesco, crabgrasses preventative, and weed be gone...... can you tell what is wrong?
Your photos pretty much show patches of dead grass. They don't look disease or insect related. Were some of these areas where the moss was growing? Moss killers really don't work all that well because they do nothing to correct why the moss was growing there in the first place. The usual situation is that the moss starts to grow in areas where the grass has thinned out due to poor conditions for the lawn. You mention one which is shade but acidic, compacted soil also can contribute to the moss. Please refer to the information we have on our website about growing grass in shady conditions,