Comments and precautions . --Some injury may be expected if heavy rains follow 

 CIPC applications on light textured sandy soils. Enlarged, injured hypocotyls, as a 

 result of CIPC treatments, appear to increase the susceptibility of cotton seedlings 

 to seedling disease organisms. Sustained high temperatures of 90° F. or more 

 reduce the period of effective weed control. 



(2) Directed post-emergence. - -For control of most small annual grasses and broad- 

 leaved weeds: Special nonfortifiedherbicidal oils at the rate of 5 gallons per acre (based 

 on 40 -inch rows) directed to the 8- or 10-inch drill area centered over the row. Oil 

 should be directed laterally to drill area at a height of less than 1 inch above the soil. 

 Apply no more than 3 treatments; they should be applied at least 5 to 7 days apart, 

 beginning when weeds first appear in the drill and the cotton is at least 3 inches tall. 

 Applications should not be made after bark cracks appear in the cotton stalk. These 

 treatments properly applied will kill crabgrass, foxtail, pigweed, lambsquarters, 

 morning glory, cocklebur, and others, but do not kill established perennials such as 

 Johnson grass, nutgrass, and vines. 



Comments and precautions . --Sprayer nozzles mustbe setproperly to avoid serious 

 injury to the cotton foliage and to insure control of the weeds. 



B. Western Irrigated Cotton Belt 



( 1) Directional post-emergence in established cotton. --For control of annual grasses 

 and broadleaved weeds from layby until harvest: Monuron or diuron at 3/4 to 1-1/2 

 pounds or NPA at 4 to 6 pounds in 40 gallons of water per acre applied on soil surface 

 between rows and on bases of cotton stalks in the row just prior to or after the last 

 cultivation. NPA has not been as consistent in controlling annual morning glory as 

 monuron and diuron. 



Comments and precautions. -- These treatments are suggested for use under the 

 irrigated conditions of the western cotton producing area only, and only on a trial 

 basis. Residual activity of urea herbicides (including monuron and diuron) on crops 

 following cotton in a rotation is being investigated. Available infornnation indicates 

 small grains planted after cotton that has been treated with monuron or diuron may 

 be seriously injured by residual activity of these herbicides. Crops that are more 

 tolerant to urea herbicides, such as grain sorghum or cotton, should be planted 

 following cotton that has been treated with monuron or diuron for weed control. 



SOYBEANS 



(1) Pre -emergence. --For control of annual w^eeds, such as crabgrass, foxtail, giant 

 foxtail, pigweed, lambsquarters, morning glory, cocklebur, and others: CIPC or DNBP 

 at 4 to 8 pounds in 10 to 20 gallons of water per acre applied immediately after planting. 

 The control of deep germinating annuals is usually less effective than shallow germi- 

 nating weeds. Will not control perennial weeds, such as nutgrass, quackgrass, Johnson 

 grass, Canada thistle, and milkweed. To reduce the cost of chemical weed control in 

 soybeans, band treatments may be made as described for cotton. 



Comments and precautions . --If heavy rains follow application and prior to crop 

 emergence, treatment may injure soybeans; if prolonged drought follows application, 

 weed control may be erratic. DNBP compounds produce vapors toxic to soybean 

 seedlings if temperatures of 88° F. or higher prevail for 5 to 10 continuous days 

 when soybeans are emerging. Temperatures of 90° F. or higher cause rapid evapo- 

 ration both of CIPC and DNBP, and may greatly reduce their period of effective weed 

 control. 



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