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WEEDS 

 2,4,5-T REGISTRATION 



The registration of liquid formulations of 2,4,5-T for use around the home and on lakes, 

 ponds, ditches, and banks has been suspended. Nonliquid formulations for use around the 

 home and on all food crops intended for human consumption may also be cancelled. The 

 registered use of 2,4,5-T for controlling weeds and brush in ranges, pastures, forests, 

 or on rights-of-ways and other nonagricultural uses are not affected at this time. More 

 details are expected later. 



ORGANIC-MATTER CONTENT AND HERBICIDE RATES 



Herbicide rates are often varied by the texture and organic-matter content of the soil. 

 Some of the herbicides most affected by the amount of organic matter are atrazine (AAtrex) , 

 simazine (Princep) , linuron (Lorox) , trifluralin (Tref Ian) , and nitralin (Planavin) --as 

 well as combination products such as linuron/propachlor (Londax) and propachlor/atrazine 

 (Ramrod/atrazine) . 



You can estimate the organic -matter content by using the Color Chart for Estimating 

 Organic-Matter in Mineral Soils in Illinois (AG-1941) . This information is also available 

 from some soil test reports. The "1970 Weed Control Guide" section of the 1970 Illinois 

 Agronomy Handbook has suggested rates for some herbicides, and can be used as a guideline. 

 Tank-mix combinations present special problems because the different ingredients may be 

 affected differently by the organic-matter content. 



Herbicides such as linuron (Lorox) and nitralin (Planavin) are not recommended for soils 

 above 3- to 4-percent in organic -matter content. Other herbicides like propachlor (Ramrod) 

 do not perform as well on soils of low- organic matter content as on those whose organic- 

 matter content is medium to high. 



Organic -matter content is only one of the factors to consider in choosing a herbicide. Also 

 consider the weeds to be controlled, and consult the 1970 Weed Control Guide. 



PRE PLANT APPLICATIONS 



AAtrex can be incorporated into the soil, but doesn't have to be. Applications can be made 

 3 weeks before planting; usually, the closer to planting time the better. 



Apply Sutan just before planting and incorporate it right away. A spray boom just in front 

 of the disk works well. Cross-disking is not essential. 



Be sure to apply Sutan accurately, uniformly --whether it is used alone or in combination 



with atrazine. This is especially true when liquid fertilizer equipment is used. Although 



not considered as a serious or extensive problem, we have had a few past cases of corn 

 injury caused by overdosing and overlapping. 



Sutan plus atrazine has given good control of both grass and broadleaf weeds. Follow the 

 same procedures and precautions as with Sutan alone. 



Lasso is now cleared for preplant incorporation for corn or soybeans, within 7 days before 

 planting. The time of incorporation for Lasso is not critical. Present research suggests 

 that preplant -incorporated applications of Lasso may be beneficial for controlling nutsedge. 

 But for the control of annual grasses like panicum and foxtail, surface applications are 

 probably best. 



