Maybe if you gave them a shot or two of Miracle Grow? Or put down some Osmocote? Try it, it might help. :)

Diann
IA Z5a

There are several possibilities, one is that there is a large tree root by the surface there and it has sucked up all the nutrients in that section as well as the available water-or a dead root that is soaking up nitrogen. Another possibility is that there is an imbalance or chemical spill, like gasoline or oil(if someone parked a leaky car on the grass) or some salt from winter or other spill in the soil and it is causing the plants to not thrive. I noticed an area in our lawn where the grass always got browner in the heat and later realized that there was an old walkway underneath that the lawn had grown over many years ago. Go figure! It's something, eventually you'll probably find out..if so, let us know what it is~