Hello, I'm new here. I used to run a lawn mowing business with a friend of mine in Massachusetts. We were two high school students just trying to pull in some extra cash and were pretty successful, with about 15 customers. Anyways, I recently moved here to Bakersfield, CA, and the business dissolved. But now is where I'm facing real lawn care problems. I was very used to lawn care in the cold and humid climate of New England. Now, I'm having real difficulties keeping my own lawn healthy in the hot and dry climate of the central valley. We had our backyard sodded about 4 months ago. The backyard was previously dirt. The landscaping company rototilled the soil and softened about 2-4 inches of soil before rolling out the sod. I believe the type of grass is Kentucky Bluegrass, though I could be wrong. A couple weeks after the grass was laid down, some small, discolored circular patches appeared in 2 areas of the lawn. These dead looking patches were surrounded by darker grass. Soon one of these developed into a huge dead spot. Here are some pictures so you guys can see what I'm talking about. The rake for size reference The dead patch has crossed over into other patches of sod, so it seems to be a problem in the soil This patch started out looking just like the first one, but never developed into a huge dead spot, but rather a large dark green patch. As you can see, the dark green has extended across a large strip of the lawn I've done alot of research on this, but I cant figure out whats wrong. I've read some stuff about fungal lawn diseases and stuff but the information is so scattered and unorganized across the internet that I really dont have a clear understanding of what it is. So could you guys please help me figure out what this is and what should I do to get rid of it/make my lawn look healthy again. Thanks!