Spent time on Rodman recently and can report that there is zero submerged aquatic vegetation present. Dam to Orange Springs and west.
The FWC/FL Dept Ag use Diquat to control water lettuce, and Rodman has water lettuce that they spray. I guess they spray under the guise of navigation on a reservoir thats not navigable for most people.
It seems that Diquat may also be an effective pre-emergent that is not easily degraded, so it hangs around a long time. I'm beginning to think this may be one of the reasons we don't see grass coming back.