It is called dollar spot and brown patch, it is a fungus. If that is what you have. We have the same grass. you can buy the stuff at Home Depot or Lowes to put in your spreader in feed it to the lawn. It will help it alot. Ours has come back looking better so far. Now we had a spot about the size of a watermelon that was not growing. I pulled out the dead looking grass put some good soil in there and put Scotts weed and feed down on the yard. The Zoysia will spread and cover it back up. Very tolerant grass.
http://www.bayeradvanced.com/guides/...FRMeDQodaVBgTA
this link might help: if you have Massey or Zoysia Green service let them know and make sure they treat it.
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