And lastly, the perennial weed has parts known as tubers or rhizomes. They will live an indefinite number of years in undisturbed areas. Studies have shown that curly dock and common mullien will germinate after 70 years. It is the eradication most people are interested in. When herbicides are used, some chemicals are developed to be very specific.
Commercial growers are most concerned.
But by merely cultivating, plowing, or mulching, one can eliminate or control most weeds in the garden or flower bed. At times they make for very unpleasant personal conditions. But, they are everywhere and don't need us and kind of do what they please.