Herbicides forest industry

Rapid growth of chemical weed control did not occur until after World War II when a herbicide was introduced by Jones in 1945 at the Imperial Chemical Industries of England 2,4-dichlorophenoxyacetic acid (2,4-D). Its utility has come from its ability to kill selectively broadleaf weeds in cereal grains, com, and cotton. It does not disturb the soil and is not persistent. 2,4,5-T was launched commercially by American Chemical Paint Co. in 1948 (now Union Carbide) to combat brush and weeds in forests, along highways and railroad tracks, in pastures, and on rice, wheat, and sugarcane. 

Dioxins are sometimes—but rarely—produced in nature, most commonly during volcanic eruptions and forest fires. Their most common source in the environment are industrial reactions in which they occur as by-products of other chemical changes or during the incineration of certain synthetic organic compounds. For example, trace amounts of 2,3,7,8-TCDD occur as an impurity in the herbicide Agent Orange (a mixture of 2,4,5-trichlorophenoxyacetic acid [2,4,5-T] and 2,4-dichlorophenoxyacetic acid [2,4-D]), which was... 

Until 1979> the primary herbicide used by foresters for brush control in the South was 2,4,5-T. This chemical could be applied inexpensively ( 15 -30/acre) at rates of 4 to 6 pounds per acre for site preparation. Most applications were conducted with aircraft. Surveys (1977) of herbicide usage on industrial forest lands in the South showed that of the 1,175,350 acres site prepared for planting, 118,100 acres (10 ) were treated with 2,4,5-T, 48,700 (4 ) were treated with other herbicides, and 909,000 acres (77 ) were treated mechanically (anonymous 1978). Obviously, the majority of the forest acreage was site prepared with machinery. Nevertheless herbicides filled an important... 

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