As a weekend gardener, I've long lamented how the most prized plants are those that are most difficult to grow and maintain. And weeds, which grow prolifically, are considered a blight on the landscape. I've wondered why this is so. Perhaps there's a Great Conspiracy -- a conglomerate of companies that specialize in fertilizer, weed killer, pest control, fungicide and plant sourcing have joined forces to brainwash people into thinking that the easiest growing plants need to be eradicated to ensure brisk business.
It reminds me of the fashion industry. Get people to despise their wide ties and bell bottom jeans in favor of straight-leg jeans and narrow ties. After sales start to dwindle and people have gotten rid of their old clothes, reverse the trend and get everyone to buy the formerly despised products and ditch their newly out-of-favor clothes. The only difference is that no one can thoroughly get rid of weeds -- they continue to spread or sow themselves year after year.
Recently I assessed the flora on our property and concluded that weeds are not our best-growing plants. Did I celebrate? No, because our best-growing plants now are actually "Invasive Plants." These are plants that government agencies are actively trying to eradicate. There are laws in place to prohibit the spread of this class of plant. No, I won't get fined or jailed for having the plants on our property. But it is illegal to traffic and transport such plants.
The term "invasive" is applied to a non-native plant when it out-competes many other native plants and has no natural growth inhibitors. Some plants actaully release a chemical that prohibits other plants from growing nearby. You can find a really good description and explanation of the issue on the United States National Arboretum Invasive Plants page, so I won't try to repeat it here.
I believe there is a silver lining to this problem. Scientists are starting to realize that some plants are actually edible and nutritious. We might even discover new medicines from these plants. Once we realize just how inexpensive it is to add invasive plants into our diets, the problem may dissolve and lead to the growth of new industry that specializes in harvesting wild-growing plants. And perhaps we can end world hunger, too.