Answer: There are a few ways - the obvious are hand pulling or hoeing the weeds. You can also use a weed wacker to chop the tops of the weeds down. If you're consistent in keeping the tops mowed or cut down, the roots will eventually run out of energy and won't be able to produce new tops. A final option is the application of thick mulch or even black plastic to keep sunlight from reaching the plants, effectively stopping the process of photosynthesis. You will probably want to work on one area of the lot at a time - 1/3 of an acre is a lot of hand-weeding!
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