CDEC at rates of 2 to 4 pounds in 25 to 50 gallons of water per acre 

 has given control of several annual weeds with less retardation of crop 

 growth than is experienced with CIPC. Use lower rate on very sandy soil. 

 Granular applications appear to be equally effective. 



Comments and precautions . --In the Mississippi River delta and some 

 other agricultural areas, fall-planted spinach may be seriously injured 

 by CIPC at rates required to control weeds. 



Lettuce 



Pre -emergence . --Experiments in Arizona have shown CDEC at 5 to 

 7-1/2 pounds per acre to be effective for control of purslane in head 

 lettuce without injury to the crop. CIPC at 1 to 3 pounds in 10 to 40 gallons 

 of water will control annual weeds. 



Onions 



Pre -emergence . --For control of a wide variety of annual grasses and 

 broadleaved weeds: A light aromatic oil emulsion at 40 to 80 gallons per 

 acre, 3- to 5-percent solution of sulfuric acid in water at 100 gallons per 

 acre, or CIPC at 2 to 8 pounds per acre applied when weeds are in seedling 

 stage but before the emergence of onions. Combinations of CIPC and light 

 aromatic oils will effectively control smartweed and purslane. 



For control of annual weeds in onion seed crops: Diuron 9 or monuron 

 at 1 to 2 pounds per acre or CIPC at 6 to 12 pounds per acre applied im- 

 mediately after the mother bulbs are planted in early spring or before 

 new growth begins from overwintered bulbs. 



(2) Post -emergence . --For control of most annual weeds in onions in the 

 loop stage: 2- to 3-percent solution of sulfuric acid in water at 100 gallons 

 per acre, or KOCN at 10 to 16 pounds in 50 to 100 gallons of water per 

 acre, applied when first true leaf of onions is at least 2 to 3 inches long 

 (loop stage). 



For control of most annual weeds in onions in the 5 -leaf stage or early 

 bolting stage, and after last cultivation when onions are being, or have been, 

 laid by and are bulbing or bolting: CIPC at 2 to 8 pounds, KOCN at 16 to 20 

 pounds, diuron or monuron at 1 to 2 pounds, or sesone 10 at 2 to 4 pounds, 

 in 20 to 40 gallons of water per acre, or a 3- to 4-percent solution of sul- 

 furic acid in water at 100 gallons per acre applied as a basal directed spray. 

 Avoid hitting tops of onion plants. The KOCN and sulfuric acid sprays should 

 be delayed until seedling weeds emerge following the last cultivation of 

 onions. 



Comments and precautions .- -Chemical and rate of application to use 

 will be determined by weeds present, rainfall pattern (summer or 

 winter), soil type, and stage of growth of onions and weeds; for example, 

 only diuron, monuron, or sesone are effective in seed onions in Western 

 low -summer- rainfall areas. 



9 Diuron cannot be recommended (as of April 1,1958) for use on onions since evidence has not been developed 

 to prove it will leave no residue or/and tolerances have not been set under Public Law 518. 



10 Sesone cannot be recommended (as of April 1, 1958) for use on onions since evidence has not been developed 

 to prove it will leave no residue or/and tolerances have not been set under Public Law 518. 



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