If you don't want to use the entire plot this year then why not cover some of it with a thick black plastic and weigh it down and leave to die off until next year.

In my experience digging it out will be hard work and not always successful. Be prepared to go back to the weeding on a weekly basis!

The best way is probably Round Up, although this can be expensive on a large area.

If you do skim some off (or have other nasty perennial weeds) a really good way of returning the nutrients is to stick them all in a barrel of water until they are no longer viable then compost them. The juice also makes good nutrient water for feeding.