Q: In mid-September, my yard is full of grasshoppers. I have every size and color you can imagine. What happened to cause this and what can I do to get rid of them?
A: Just about any landscape insecticide will kill them when they are less than an inch long. When larger, insecticides are less effective.
I imagine yours are pretty big now so all I can suggest is making two sprays of insecticide seven days apart. That should give you enough control to make things better.