Herbicides 293 



acetic acid. Others are effectively transported in plants, as are the ar- 

 senicals and sulfamates. Auxin herbicides take their place among these 

 materials as highly effective and highly selective killers which give 

 weed control with remarkably low application rates and their prop- 

 erty of ready translocation through plants particularly enhances their 

 value. 



Auxins find their greatest agricultural use as herbicides. With the 

 60,000,000 pounds of 2,4-D produced in the United States in 1952, it 

 may be estimated that approximately 50,000,000 acres of land were 

 treated with this herbicidal material. 



