Thank you all for responding to my query.
To answer a few questions: the ground is not loose soil, but more clayee, and it gets several hours of sun a day. Needless to say, the weeds thrive without being watered directly, but a hose can be dragged back there as needed to make sure things get watered and started nicely.
I am not interested in sterilizing the soil. However, I have no problem using Roundup or Spectracide or whatever to kill what they can, and doing my best to dig up the nutsedge and other evil things that remain therein. Since herbicides of that ilk say that the ground is OK for planting in several days, I figure they are not going to do too much damage. (And yes I have used them in the past.)
This is an area that is unused and unseen. Frankly, if I thought something like gravel would work as a cover, I would be happy to have someone come by with a truckload and spread it (thank you very much). But as noted, stuff will rise up through that. The idea of covering the whole area with a weed barrier and letting it lie there for a year sounds like a good idea. I can then think about whether I want to seed the ground with veth or clover or something else (nothing that gets too tall) upon removing the cover. Or I could have gravel laid over the cover.
Note: As you can see in the photo, the tricky part with the barrier is going to be getting it around the humongous stump, which has major roots spreading out. I am guessing that as for that portion, actual stapling may be the way to get the material affixed in place. There are also pieces of slate and etc. that will need to be gotten rid of as well. Much of the nutsedge is off camera.
But thanks again.
