Weeds are considered the enemy of many gardeners and homeowners who want perfect looking lawns. Weeds can choke life from plants, flowers and lawns. Weeds also cause problems for food crops. Because of the weed problem, chemicals called herbicides have been created to kill weeds. Herbicides are a a recent invention used for both weed control and warfare.
The first herbicides were in the form of sprays used to control broad-leaved invasive plants in cereal crops. This occurred in the final decade of the 19th century. The U.S. Army also began using sodium arsenite in waterways to control aquatic plants. Sodium chlorate was the first in 1925 to be directly applied to the soil. Sodium nitrocresylate was introduced to the U.S. from France in 1934 as the first selective weed killing herbicide.
Organic herbicides arrived in 1945 in the form of 2,4-D; 2,5-D and 2,4,5-T, which were growth-regulating chemical acids. These were mixed to form a combination herbicide, which would take the name Agent Orange due to its color. From 1965 to 1970, the U.S. used this herbicide as a defoliant during the Vietnam War.
In the late 1940s, 2,4-D became the first widely used herbicide and was seen by many farmers as a miracle cure for crops. This herbicide was first made commercially by the Shirwin-Williams Paint Company. It is still one of the top five herbicides used today. In the 1950s the triazine group of herbicides was created; the most known and most problematic is Atrazine, which has proved fatal in high enough levels of use.
Glyphosate is a chemical herbicide known by the trade name Roundup and is manufactured by Monsanto. It came to market in 1974 as a nonselective weed control; today it is the most used weed-controlling herbicide by farmers to control weeds in crop growth and by homeowners to control weeds in gardens. The success of Roundup comes from the fact that Monsanto holds patents to nearly all commercial and privately grown plant genetics in the U.S. This allowed the company to create plants that are immune to glyphosate.
Along with the "Green Movement" and environmental concerns came the call for non-petroleum-based weed killers. Natural herbicides have started to include clove oil, table salt and vinegar-based compounds. These alternative herbicides have proven nontoxic to humans but are not as effective as traditional herbicides. Brands of alternative herbicides include "AllDown," which is vinegar-based, and "Burn It Out," which uses clove oil.