smartweed

I have several large patches of Pennsylvania smartweed and nutsedge. They are taking over my yard.  I reseeded a large area, but would like to rejuvenate the remaining grass.  How can I win against these two stubborn weeds?

I have no experience with either of these and I know that some folks will hold off on responding to see what I say.  So ....  can anybody else help here?

I am not sure exactly what they are but I googled them and one ag site said to use a pre emergent. The only one that I can think of is corn gluten. I have never used it ,(yet ) but you could give it a try. Let us know how it works. The other thing is to use Paul Wheaton's advice on weeds.Mow high, water infrequent, and fertilize ( no chemicals please  ) Good luck !

Thanks for your advice.
    I was feeling rather isolated for resisting the commercial approach to weed control.  This is really an informative site.

If they are annuals, you can beat them pretty easily by mowing high and watering infrequently.  The frost will kill them this year.

Bad news. Nutsedge is a perennial. I am not sure what smartweed is.
http://msucares.com/lawn/lawn/weeds.html
Where I do not like this sites idea on weed control, I did find it very informative.

Nutsedge is a perennial but smartweed is an annual. Here is a better site for weed identification.
http://web.aces.uiuc.edu/weedid/

http://www.turf.uiuc.edu/weed_web/index.htm
This is another good site.

You can eat the smart weed leaves in salad.
They are a member of the buckwheat family so will do a
similar function as buckwheat in your garden.
peace, Julie