Well, even if it was all weeds, I wouldn't plow it under, I hope you aren't serious about that. Deal with it in the spring and try again. Weeds will be a different type of potential food source and cover. I am in NW IA, we started with good moisture in the ground, but very little rain this summer, that didn't doom our plots....it was ground squirrels of all things! Not sure how to deal with them, planted some of the plots 3 times...they were hungry.