Since we haven't had a hard frost yet in Grand Forks (we've only flirted with 32 degrees a few times overnight), I thought I'd give you an update on the lawn.
I put down weed killer right after Labor Day and there are very few weeds in the lawn now. Steve Sagaser from NDSU Extension says the fall application will also help cut down on weeds in the spring.
The grass is also looking nice and green thanks to all the rain we've had this fall locally. Steve says you can cut back on watering in the early fall to about a 1/2 inch a week, rather than a full inch. I didn't have to water much at all since the last week of August thanks to some timely rain.
While my work this summer paid off in a lot of way, some of the root problems with my lawn remain. I have too many patches of grass that don't match other grass in the lawn. Some of this has to do with me using the wrong seed in the past to re-seed and do patch work. Other problems go back to the original effort to seed the lawn. I definitely will be re-seeding some areas in the spring to try to bring some uniformity to my lawn.