effective as pre -emergence treatments and often fail to control established weeds. 

 Such treatments should be used only as emergency measures. 



Comments and precautions . --Less likely to cause injury if applied when soil 

 temperatures are low. Certain varieties of pumpkins and squash are not tolerant to 

 this treatment, and varietal responses should be known prior to large-scale use. 



Carrots, Celery, Dill, Parsnips, Parsley 



(1) Post-emergence .--For control of small annual weeds on muck and upland soils: 

 Application of undiluted special light aromatic oils at 80 to 100 gallons per acre applied 

 w^hen weeds are 1 to 3 inches tall, and, in case of carrots and parsnips, before taproots 

 are more than 1/4 inch in diameter. Most effective if applied when air movement is 

 downward and relative hunnidity is high. Light aromatic oils should only be applied to 

 celery when in seedbeds. Later applications on the other crops may result in off 

 flavor. 



Cucumbers 



(1) Pre-emergence and post-emergence. --Same as for cantaloupes and muskmelons. 



Lettuce 



(1) Pre-emergence. --Same as for cabbage. 



Onions 



(1) Pre-emergence . --For control of a wide variety of annual grasses and broad - 

 leaved weeds: A light aromatic oil at 40 to 80 gallons per acre, 3- to 5-percent solution 

 of sulphuric 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 prior to emergence of onions. Combina- 

 tions of CIPC and light aromatic oils will effectively control smartweed and purslane. 



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

 2 to 3 percent solution of sulphuric 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 and after last cultiva- 

 tion when onions are being or have been laid by and are bulbing: CIPC at 2 to 8 pounds, 

 KOCN at 16 to 20 pounds, and monuron at 2 pounds in 20 to 40 gallons of water per 

 acre, or a 3- to 4-percent solution of sulphuric acid in water at 100 gallons per acre 

 applied as a basal directed spray. Avoid hitting tops of onion plants. 



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

 determined by weeds present, soil type, and stage of growth of onions and weeds. 



Peas 



(1) Preplanting . - -For control of wild oats and other grasses in Intermountain region: 

 IPC at 3 to 6 pounds in 10 to 40 gallons of water per acre applied to the soil, and 

 thoroughly disked into soil surface 2 to 4 weeks before planting. 



(2) Pre -emergence . --For control of annual weeds in Northeastern region: Any one 

 of several amine salts of DNBP at 4 to 6 pounds in 10 to 20 gallons of water per acre. 



I 



(3) Post-emergence .--For control of most broadleaved annual weeds in all pea- 

 producing areas: Amine salt of DNBP at 3/4 to 1-1/4 pounds in 20 to 40 gallons of 

 water per acre applied when weeds are small and peas are 3 to 8 inches tall. 



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