(1) Weeds rob other plants of nutrients, water, and, crucially, sunlight. (2) This means they attack other plants indirectly. (3) People who mostly view cornfields from an airplane window probably do not appreciate how much of farming consists of keeping weeds away from crops. (4) A number of weeds are edible and can be used for food or herbal medicine. (5) The very word "cultivate" means not only to make something grow but also to plow the soil, which was the original method of weed control- uprooting unwanted plants and burying their seeds. (6) A single ragweed plant, if left unchecked, can reduce the yield in an area holding 30 soybean plants by as much as half. (7) Thus it is no surprise that farmers were excited when technology was developed to breed crops that were resistant to glyphosate, the most widely used herbicide in the United States. (8) Entire fields could now be treated with glyphosate, but only the weeds were eradicated and not the valuable crops themselves. (9) But now farmers face a new problem, one that many agricultural scientists would say was inevitable, that is the weeds themselves have developed resistance to this herbicide. (10) These resistant plants are often referred to as "super weeds." (11) Several weed species throughout the world have already developed this resistance. (12) And while there continues to be hundreds of species that remain susceptible to glyphosate, the ones that do show resistance are some of the most prolific and difficult to eradicate. (13) They also tend to infest some of the most common crop types: cotton, corn, and soybeans.