Some inbreds and some hybrids are more easily injured by 2,4-D than others. It is 

 usually best not to use 2,4-D on inbreds unless you are certain they have a high 

 tolerance. Single crosses may or may not be more sensitive than double crosses, 

 depending on the sensitivity of the inbred parents. Doublecross hybrids and three- 

 way crosses also vary in their sensitivity, depending on their genetic makeup. 



To help avoid damage to corn, be sure to apply 2,4-D at no more than the recommend- 

 ed rate. The suggested rates per acre for broadcasting are: one-sixth pound of the 

 low-volatile ester, one-fourth pound of the high-volatile ester, or one-half pound 

 of the amine. 



The ester forms of 2,4-D can volatilize. If this happens, the vapors can move to 

 nearby susceptible plants, causing injury. Since the amines are not as volatile as 

 the ester forms, the amines are less likely to injure nearby plants. However, when 

 either the ester or the amine forms are used, spray particles can drift to nearby 

 susceptible plants. 



It is important to spray weeds when they are small. This is when they are easiest to 

 kill, and before they compete seriously with the crop. However, you can use high- 

 clearance equipment relatively late in the season if you wish, especially for the con- 

 trol of late -germinating weeds. Many such weeds are not very competitive with corn, 

 but control would decrease the production of weed seeds. Do not apply 2,4-D to corn 

 from the tasseling to the dough stage. 



Amines are salts that are dissolved to prepare liquid formulations. When mixed with 

 water, they form clear solutions. Esters of 2,4-D are formulated in oil. When they 

 are mixed with water, they form milk emulsions. 



Dacamine and Emulsamine are amine forms of 2,4-D that are formulated in oil. Hence 

 the name oil-soluble amines. Since they are formulated in oil like the esters, they 

 are said to have the same effectiveness while retaining the low-volatile safety fea- 

 tures of the amines . 



The active ingredients in all formulations is still 2,4-D. When you adjust rates 

 appropriately to provide both weed control and crop safety, the various formulations 

 are usually similar in their effectiveness. 



Banvel is more effective than 2,4-D for controlling smartweed. But serious problems 

 have developed in previous years because the Banvel affected nearby soybeans and other 

 sensitive plants. The closer the soybeans are to blooming when the Banvel hits them, 

 the greater the risk of reduced yields. 



For further details on Banvel, refer to the 1972 Weed Control Guide and product labels 



Atrazine and oil should not be used after June 10 if any crop other than corn or sor- 

 ghum is to be planted in the field next year. Although you may hear an occasional re- 

 port of grass weeds taller than 1-1/2 inches being controlled with atrazine and oil, 

 don't expect to do it. And don't expect significant increases in controlling larger 

 grass by using higher rates. 



Outfox can be used on grass weeds up to four inches high and for corn up to ten inches 

 tall. A limited amount has been available. Some temporary leaf burn or stunting of 

 corn may occur. Do not plant treated areas with any crop except corn until the fol- 

 lowing year. 



