When exactly did people come up with the idea that weeds were bad? When did a weed become a weed? How it was that one day the world was simple, a Garden of Eden, full of plants, and the next, those plants had been slotted and reduced into a hierarchy of good and evil? Some plants are good. Some plants are just plain evil. Ralph Waldo Emerson suggested that a weed is simply "a plant whose virtues have not yet been discovered." A more prosaic dictionary definition describes a weed as a wild plant growing vigorously where it is not wanted; it is an awfully broad concept. One could easily lump valuable native plants with invaders that choke out anything in their path.
Even if you buy the idea that some wild plants are inherently and indistinctly more valuable than others, the lines soon get muddled. Are violets weeds? Jack in the pulpits? Asters? Buttercups? Columbines? Wintergreen? If beauty is in the eye of the beholder then chicory, goldenrod and Queen Anne's lace cannot possibly be weeds. In most cases, as you well know, you know a weed when you see it. Thistles, ragweed, dandelions, plantain, pigweed, burdock .
And then there is another whole category if so called noxious weeds, one that can infest field crops, reducing yield from the crops such as barley and soybeans. But while there are plants that clearly will suck up nutrients and crowd out other , more desirable species it is oversimplifying to assume that all weeds all bad and up to no good.
It is not a case of running out and protecting a stand of horrible invasive weeds such as purple loosestrife in a ditch. So called "weeds "play very important roles in nature. Weeds work to control erosion Weeds distribute nutrients in soil. Weeds serve to fix nitrogen nutrient into the soil. Weeds attract pollinators to other more desirable plants. Weeds provide needed shelter for wildlife. Weeds can even be a present and future food and medicine. Anyone who has ever tried to plant garden or seed down a backyard has noticed that if you leave a patch of earth bare for a whole the first things that collect , grow and colonize there are weeds. You may not like weeds but without weeds the soil would blow away or bleed away as soil runoff with the first major rains of spring or summer rain storms. Fast growing weeds indeed quickly throw down roots that keep the soil in place to prevent soil and landscape erosion. Indeed weeds are also a reliable source of information about the health of soil and fields. Plants such as sorrel and horsetail indicate acidic soil; plantain indicates compacted soil: Canada thistle, clay soil and chamomile will well indicate the presence of alkaline soil. Finally nettles, pigweed and lamb's quarters are all signs of good fertile grounds.
So in the end it is all in the eyes of the beholder. What is a weed? Is a weed a good thing or a bad thing? It depends on your perspective as well as your property - whether it is a lawn, garden , forest or beach lake cottage's needs or your wants from a gardening , lawn or aesthetic need.